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This is not a comprehensive - all encompassing in-depth history of every known audio format since mankind had emerged from the swamps, but for the most part, is comprised of the formats we currently support. One day as time allows, we hope to add to this. Thus it'll always be perhaps, a work in progress !
On December 4, 1877 Thomas Edison became the first
person to ever record and play back the human voice.
The technology that led to the phonograph came from developments that Edison made in the telegraph and telephone. Edison at the time was experimenting with how a moving diaphragm linked to a coil, could produce a voice modulated signal. Meanwhile, he was also experimenting with a telegraph repeater which was simply a device that used a needle to indent paper with the dots and dashes of the Morse code.
Out of these two ideas, came the concept of attaching the stylus from a telegraph repeater to the diaphragm in the mouthpiece of a telephone. The first test in July of 1877, involved a sheet of paper pulled under the needle mechanically coupled to a diaphragm, as he shouted into the mouthpiece..... Sadly, It didn't work..... though it did produce an unrecognizable sound which was luckily, just enough to prove the concept and spark intense interest in developing a solution to the problem of recording the human voice. (Had he only imagined at the time what it would all lead to !)
For the next year Edison and his staff worked on the solution. Tin foil replaced paper, and thus tin foil became the first viable recording media. A band of tin foil was mounted on a cylinder, and the cylinder was turned via a hand crank during the recording and the playback. Edison turned the crank and spoke the first recorded words. "Mary had a little lamb, its fleece was white as snow, and everywhere that Mary went, the lamb was sure to go." Of course, the rest is history !
However, it's not unusual for history to get things "twisted"....... Jean-Paul Agnard suggested the following scenario.... A possibility exists that Edison himself in fact, might not have been the very first person to have recorded and played back the human voice. This was most likely made by his 2 key assistants: Charles Batchelor his chief assistant and John Kruesi his head machinist, to whom he directed to have the tinfoil phonograph fabricated from his original drawings. From what can be deduced from their notebooks and punched time work cards, it is most likely they made a test recording first to see if it worked before presenting the completed device to "The Boss". Thus In all probability, it was either Charles Batchelor or John Kruesi who actually recorded the first human voice. But it was much more romantic for history to have recorded that Thomas Alva Edison voiced "Mary had a Little Lamb" to be the very first audio recording. Thus who actually voiced the very first recorded words be it Charles Batchelor, John Kruesi or Edison himself, remains unclear. If it was in fact either Batchelor or Kruesi, is perhaps a historical academic point.... for without Edison's plans, neither Batchelor or Kruesi would have been able to "pull it off" !
After inventing the very first successful audio recording device, Edison got side tracked and didn't get back to developing the phonograph for about another 10 years. By that time, his patents had expired and by that time, others took interest in the invention. One of those, was a fellow by the name of Tainter who worked for Alexander Graham Bell. He made a major improvement, by using a wax cylinder as the new "state of the art" recording media, as well as making improvements to the reproducer itself, and applied for patents in 1885.
Thomas Edison regained renewed interest in the phonograph in 1887 (probably driven more so to keep competitors at bay than anything else) and in 1887, he formed the Edison Phonograph Corporation to market and sell his creation.
Edison was a much better inventor than business man, but eventually the market became so huge that even HE couldn't help but making piles of money, selling both phonographs and recordings to a "hungry" market.
There is wealth of additional information on Vintage 78's. Read More.....
Ediphone - Dictaphone (1878) - (1916)
The Ediphone and subsequent wax cylinders used in Edison's other product lines continued to be sold up until 1929 when the Edison Company Folded.
The name "Dictaphone" trademark was originally registered by the Columbia Gramophone Company in 1907. Dictaphone was spun off into a separate company in 1923 and continued manufacturing wax cylinder dictating equipment up until 1947 when it introduced the Dictabelt, which subsequently replaced the old wax cylinder technology.
The Dictaphone and Ediphone were for practical purposes, almost identical products. So similar were the machines, that the cylinders could actually be interchanged between the two. Columbia (one of Edison's fierce competitors) called their machine the Dictaphone (a trade name still familiar today).
Edison initially sold his phonographs intended for business dictating use under the phonograph name. This led to product line confusion and Edison finally renamed his phonograph line intended for business dictation to the Ediphone in 1916.
The technology was similar to the original phonograph, with the main improvement being the paraffin coated cylinders used for recording. The main advantage to the paraffin cylinder, was it's capability of being erased and re-used - the first technology that allowed repeated erasures (up to a point anyways). This was a major selling point over Gramophone based equipment (for this application anyways...)
Erasure was accomplished via of an optional "Shaver". As it's name implies, it literally shaved off the soft paraffin recording, yielding a smooth surface upon which to record new material. Cylinders could be re-used til there was no longer any paraffin left on the cardboard tube.
Early Cylinders could only record up to about 2 minutes of dictation. Larger cylinders combined with a smaller track pitch, increased recording times 4 fold to about 8 to 9 minutes per cylinder.
As the cylinders age, they lose some of their resiliency and become somewhat brittle. Thus they are prone to being chipped - especially at the ends.
The organic nature of paraffin combined with high humidity often caused mold to grow in the paraffin, yielding them unplayable. For cylinders properly stored in low humidity temperature controlled environments, these cylinders often contain the only early audio recordings of family members or corporate history.
Pictured to the right is our pristine Model 12 which we discovered in virtually brand new condition !
Meanwhile, while the phonograph was being developed, a German immigrant by the name of Emile Berliner, settled in the city of Washington, D.C. and also took an interest in recording technology. In 1888 he filed and patented a talking machine which also recorded and played back sound.
The technology was very similar... But instead of using a cylinder, Berliner used a flat recording disc and a stylus which cut a spiral groove while the stylus in the cylinder moved up and down in vertical cut recording format (known also as the "hill-and-dale" vertical cut) to record the actual audio.
Berliner called his talking machine the Gramophone.
One of the main advantages of a flat medium disc, was that thousands of records could be inexpensively pressed from one master. The Gramophone soon became the worldwide standard.
It's somewhat ironic that the original Phonograph was a cylinder based device, whereas the Gramophone was always a flat record based machine. Today, the phonograph term is commonly mis-associated with being a turntable for playing records, when in fact it never did. When you see a record player, you should be thinking "Gramophone", and NOT "Phonograph" ! .......... Marketing and subsequent public name recognition sometimes gets things twisted around backwards ! - Much of the proper name confusion came about when Edison was forced to "eat crow" and throw in the towel on his phonograph cylinders and finally begin to sell Gramophone compatible equipment to take advantage of the exploding market for recorded music.
Pictured to the right is our fully restored "His Master's Voice" Gramophone Model 103 manufactured in Hayes, Middlesex, England - Circa 1925. Small, lightweight & "portable" with a hand crank spring motor, it was the "iPod ®" of the period.
There is wealth of more information on Vintage 78's. Read More.....
Read a bit more on Emile Berliner and "Nipper" - The RCA Dog and how it all came together... Click here.....
(1930)Before there was magnetic tape, there was wire !
Yes.... there actually was such a device ! ....... and they became quite popular from about 1947 to 1952 before open reel magnetic tape finally replaced them.
Much early family history resides on those early wire recordings and they are holding up quite well to the test of time quite well.... much better than newer magnetic tape is !
We have an entire page dedicated solely to the Wire Recorder..... it's history, pictures, how to make splices and tips on how to acquire one.
Click here to go to the Wire Recorder page...
Somewhat
out of the time sequence, but will be listed here to keep all wire recorders
grouped together...
The Minifon was released in 1951. It's main attribute was it's small portable size and claimed to fit in one's shirt pocket (assuming I suppose. one has a Gi-normous shirt pocket !.... ) Nevertheless, compared to the Websters and Silvertone home machines etc, it was indeed truly portable. The P55 (the most popular) measured approx 7x4x1.6". It was powered by 3 batteries: a single 1.5 v filament battery (AA size), a single 30 V anode battery (plate voltage supply) and a single 12V battery for the reel/capstan motor drive. An optional AC adapter was available that only supplied 9-12v for the motor drive, which was the battery with the shortest life and also (naturally) the most expensive.
The filament battery had a life expectancy of 20 to 30 hrs, the anode battery: 150 to 200 hrs, and the motor battery: 10 to 12 hrs.
The included microphone served as both a microphone as well as a speaker - - though an optional telephone pickup, headphone, as well as a dedicated "full" sized speaker was available at additional cost. The P55 initially sold for $289 here in the US back in the early 1950's (quite a hefty sum back then), but it was truly portable and considered state of the art "microminiaturization" for it's day. The P55 employed vacuum tube technology with 3 "micro" (and considered highly power efficient) vacuum tubes. Since it was battery powered, a rectifier tube and thus power supply was not required, as all operating voltages were supplied from the 3 on board batteries (that alone saved a lot of weight and significantly reduced the number of required components) Not surprisingly, it was quickly adopted by many governments as being the ultimate "spy" recorder of it's day. Minifon even designed a wristwatch microphone, that looked like a watch, but was actually a microphone ! Today, that wristwatch microphone is somewhat of a collector's item.
Fidelity was on par with the full size Websters, despite the wire size being nearly half the thickness of the much larger Webster reels (which was already hair thin). Due to the extremely thin wire used, wire breaks are far more of a problem. Minifon also opted for non-standard spool sizes and recording speed, insuring that only their equipment could be used for playback. Standard Webster style reels recorded at an industry agreed on 24 ips, while Minifon used a proprietary 30 cm/sec or about 11.8 ips.
Soundscriber was another competitor in the growing dictation marketplace.
Flexible vinyl records were "cut" using a stylus cutting head,
and playback was made on a dedicated player as the model shown here.
Though we used the term "cut" to convey the concept, in reality, the groove was
instead "pressed" or imprinted into the soft vinyl by the stylus. Interesting to
note, is that this was one of the early uses of vinyl as a recording medium. The
pressing or imprinting technique has one major benefit over literally cutting grooves
on harder mediums such as acetate - namely, the imprinting technique using a soft
vinyl which acted almost like a lubricant for the stylus, results in much lower
surface noise.
Corporations loved them, as like soon to follow Dictabelts, the media could not be accidentally erased and were easy and inexpensive to mail.
Soundscriber media came in two sizes:
15 minute "Mail Chute" discs on 6 inch media... and
8 minute "Memo Discs" on 4 inch media
Soundscriber discs are easy to identify, owing to their unique square spindle hole cutout and translucent green color.
Audio fidelity was greatly improved over the earlier wax cylinder technology and similar in quality to that of Dictabelt equipment. The soft media did not lend itself to repeated playing (usually 10 -15 plays before wear would become evident) but was more than sufficient for dictation purposes. Soundscriber used their own recording speed and requires a special stylus to play them. Use of a standard 78 stylus will damage the grooves.
Being stylus based, vibration of the unit could result in skipping - especially where so many offices of the day were in wooden mills, prone to the floors shaking as heavy materials were being moved about or a heavy footed co-worker walking close by. To solve that problem, (or at least greatly reduce it) Soundscriber sold a shock absorbing cradle from which the recorder/player was suspended.
The Soundscriber was "done in" by the soon to follow Dictabelt, which soon captured most of the dictation market. Though it made reasonable market penetration, it should have been much more successful than what it was, as the mechanism was far simpler and less expensive to build, being no where's near the mechanical complexity of a Dictabelt machine. It actually worked quite well ! But alas, effective marketing & consumer perceptions are often fickle things....
Like all the early media, Soundscriber discs often contain the only recordings of family members, as executives would sometimes bring one home on the weekend to make family recordings !
Manufactured by the Dictaphone Corp.
®, the "Dictaphone" trademark was originally
registered by the Columbia Gramophone Company in 1907. Dictaphone was spun off into
a separate company in 1923 that specialized in the sale and marketing of dictation
equipment that continues a fine tradition to this day !
Up until 1947, Dictaphone sold and marketed it's line of wax cylinder dictation equipment to compete with Edison (of the "Thomas Alva" fame). But by 1947, Dictaphone saw the "writing on the wall" for the original wax cylinder technology, and developed what they trademarked to be the Dictabelt. The Dictabelt promised to be a quantum leap forward in dictation equipment technology... and & it was a promise well kept !
As the name implies, Dictabelts are flexible belts of vinyl .005" thick by 3 1/2 inches wide with a circumference of 12 inches, which allowed up to approximately 15 minutes of recording time per belt. It's basically nothing more than a record in the form of a flexible belt - not much unlike in form, to a small belt that may go on a belt sander ! However, unlike wax cylinders that could be shaved (read: erased) and reused several times, the Dictabelt was not erasable or re-useable... In modern terms you could think of them as being audio WORM drives (Write Once - Read Many) .... The belts were made of soft flexible vinyl that allowed the recorder to imprint a groove much like a record cutting lathe. Unlike a record cutting lathe, the grooves are not cut, but instead like the earlier Soundscriber, the grooves are imprinted (or embossed) onto the belt.
Belts came in either red, blue or purple depending upon the year of manufacture, but other than the color, were identical in all other aspects....... "Designer colors to match any office decor" ! - (well..... as long as it was red, blue or purple anyways...) Red belts were made from 1950 to 1964.... Blue from 1964 to 1975.... and purple belts from 1975 onwards. Playback was via a stylus - similar (at least in concept) to that used in a record player. Audio quality of belts properly recorded and stored is quite good, and was a quantum leap forward from the low fidelity of wax cylinders.
Dictabelt also offered a 30 minute machine that used the same belt media. To achieve 30 minutes per belt, a narrower stylus and half the track pitch was used in comparison to the standard 15 minute recorded belts. However, the narrow track pitch often resulted in many skips if the stylus was the least bit worn or tracking mechanism/ lathe was not properly adjusted & kept well cleaned & lubed. Cutting head static pressure was also much more critical as well as having a sharp cutter stylus. Because of those reasons and associated maintenance expenses, the 30 minute machines never really caught on....... Mostly due to the much higher maintenance costs which normally entailed the local Dictaphone service rep having to make many a visit to keep one of those "beasts" properly working. Put another way, it was simply a bit too "finicky", whereas the 15 minute recorded belts were much more reliable - even on machines in need of servicing...... Thus 30 minute belts are quite rare.
Dictabelts when properly stored, are holding up
amazingly well - especially when you consider that most magnetic tapes from even
the late fifties & early 60's are now unplayable due to oxide shedding. The very
early belts tended to become brittle and break at the splices, but different manufacturing
technology resolved most of those problems using a different composition more resistant
to hardening with age (ie: exposure to ultraviolet light). Different manufacturing
techniques also resulted in effectively extruding a seamless belt, which did away
with the need of splicing the ends together during the manufacturing process, which
was always the weakest point and prone to early failure - especially as the belts
aged. Based on what we've seen so far, Dictabelt recordings will probably still
be playable in another 50 years if properly stored...... The only common malady,
is that as they age, they tend to lose their suppleness over time
(don't we all, huh ?)........ and since most were stored flat, they
almost always developed stubborn unyielding folds (ditto that
also...) Most belts require special treatment & restoration techniques
to restore their shape and flexibility.... Otherwise, skips, as well as hearing
the two "folds" (which sound like loud repetitive "thumps"- two per each revolution
of the belt) as they pass under the stylus is common. The effects of this
restoration process are short lived, but allow most belts to be transferred
with only minimal problems related to their being folded/flattened for so long.
Dictabelts were never intended as being archival media, though they have outlived many of their later to come magnetic tape media. The soft vinyl yields up to 20 plays before groove wear begins to take its' toll if played with a sharp stylus. Since most dictation applications required no more than 1 or two passes, it was not an issue for the dictation transcription purpose intended.
Their small size also made them easy to mail as well as store, and soon became the defacto standard of many large & medium size offices. When new, the belts were extremely supple, and could easily be flattened into a mailing envelope or preferably a small box, with few if any consequences. Field offices could receive audiograms or even personalized audio messages/dictation in several days via the USPS..... Naturally, the Dictaphone Corp sold 10's of thousands of em !
The Dictabelt machines were built like tanks and were mechanically over-engineered to put it mildly. Other than a belt and a rubber idler wheel & replacement styli, the drive mechanism if kept lubricated and maintained, will most likely outlive many generations of potential users..... ( some yet to be born ! ). Having rebuilt and maintained many a unit, I can personally attest to the fact that Dictaphone® built one tough machine ! Short of being thrown out the window of a 5 story building (where it's not unlikely that the concrete below might sustain the most damage), the basic drive mechanism would most likely survive any torture even a "sick" demented office worker could conjure up ! By the time Dictaphone Corp switched to tape, they had by that time an understandably loyal following of Dictabelt users and a huge installed base, which made the transition to tape an easy sell. Had it not been for the Dictabelt, Dictaphone Corp probably would have gone the way of Edison. Though "built like tanks", they did however require lubrication, occasional adjustment & alignment to keep the belt tracking true on the mandrels.
Although the belts and recordings are holding up pretty well even after 50 years or so in many cases, finding a working Dictabelt machine today is quite rare. Even scrap "parts machines" are becoming hard to find. Sadly, most firms just tossed perfectly good working machines into the dumpster back in the early 60's, to make way for the new tape based dictation equipment....... (enough to make one cry today)....... Yet another case where the media again outlives the availability of the equipment on which to play it.......
* * * * * * * * * * * * * * * *
The top image shows the internal layout of the machine with top skin , log/note panel, and cutter head assembly removed. This machine has just been completely re-built, cleaned, & all rubber parts replaced. Even sports a brand new stylus from a lot of 10 we were lucky to locate from a former retired Dictabelt Service rep several years ago ! Placed alongside a new machine from the factory, you'd now be hard pressed to tell the difference !
For those familiar with the internal workings of Dictabelt machines, you'll also notice that the "cutter" head has been removed. Since there is no such thing as "write inhibit" on Dictabelts, we remove the cutter head to prevent any accidental recording-over of pre-recorded belts. We do this on all our machines with the exception of one that we still use as a recorder.
The image depicts both the red and blue Dictabelts. These are the second generation belts that are seamless - ( The early 1947 to 1950 belts being so prone to break at the early splices where the two ends met. Note that these belts have been specially processed to restore their natural round shape. Most belts when received after having been stored flat for nearly 50 years, appear by comparison, to have been "mashed" almost flat in a grape press ! Where sharply creased, the vinyl deforms and even after restoration 2 "thumps" per revolution can often be heard as the remains of the creases pass the stylus.
Dictabelts were marketed for office dictation purposes and never really caught on as a consumer recording device........ though many an executive brought one home on the weekends to make early family recordings or recordings of the family when they came to visit Dad at the office....... The reason for this, was undoubtedly, the relatively high cost of the machines; owing to their rugged high quality commercial construction & associated costs. Had a cheaper consumer machine have been designed & marketed, no doubt the Dictabelt would have been a major player in the consumer marketplace & have given Wire Recorders a "run for their money"........ Alas, Dictaphone Corp. targeted the commercial office market, and never delved into the consumer marketplace.
The "hay-day" of Dictabelts, spanned a period of nearly 15 years from 1947 to 1962. Ultimately, Dictabelt machines were replaced with magnetic tape technology, and Dictaphone ceased production of Dictabelt machines by the early 60's. Even though out of production for nearly 20 years, some remained in daily use at large firms up until even 1980..... yet another testament to their quality of construction..
Perhaps one of the most "colorful" media (I couldn't resist making these images a bit larger) , the Dictabelts are often the only remaining audio recordings of family members or corporate history from 1947 to as recent as 1980.
In the case of brittle belts or belts that are stuck together, do not attempt to "open" the folds or separate the two, lest you end up with "Dictabits" ! Salvaging those, requires special techniques !
To listen to one of the earliest Dictabelt Transcription Recordings - Circa 1947 of a WW-II medical report dictation: Click Here (794k mp3)
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The Tascam 34 is a 3 head 4 track discrete ATR. It was used by both professional and hi-end audiophiles. |
The first audio tape machines were open reel to reel, and evolved into a wide number of tape widths and track configurations.
The first being the Ampex Model 200 released in 1948 and purchased by ABC for the recording of delayed broadcasts. By 1954, Ampex began marketing the first multi-track machines, and the stage was set for the switch from Dictabelts & Wire Recorders to magnetic tape.
Open reel to reel was the predominant format, from audio tape's inception, to the early 1980's, when digital started making in-roads.
Popular tape widths ranged from 1/4 inch to 2 inch, while track formats ranged from 1/4 inch mono to discrete 32 track analog 2 inch tape - and almost anything in between ! Tape speeds ran the gamut... 15/16, 1 7/8, 3 3/4, 7 1/2, 15 and 30 ips.... Though 1 7/8 to 15 ips are the most common. 15/16 ips was normally relegated to the 24/7 of police and military recordings of phone transcriptions and shortwave interceptions.
1/4" consumer machines typically used anywhere from 1⅞ to 7½ ips, while 15 & 30 ips speeds were normally found only on the professional machines.
Early home and educational classroom recorders such as the Wollensack most of us remember from our school days of the 50's, were all reel to reel. The transport system was both simple and highly reliable. As the consumer moved on to the "no thread" - "idiot proof" cassette and cartridge systems to come, the professional community stayed with the open reel to reel. Since much early editing was done literally by "Cut and Splice", open reel had a distinct advantage, and most early professional decks came with a built-in splicing block. Advancements in solid state electronics and motor servo systems made these transports a dream to work with.
Various open reel formats remained the professional's transport of choice from it's early inception, to it's slow demise, when it was retired in favor of the newer evolving digital formats.
Some of us still prefer working with the open reel to reel machines. High quality analog audio has a certain warmth and richness of sound so far unachievable by the seemingly harsh digital encoding technology of present.
The beauty of these machines are their availability on sites such as eBay. Many of the transports have had little use, and are in virtually new condition. Typical prices in the mid 80's for a good 1/4" 4 Track such as Tascam or Otari started at around $3000 while 1/2" 8 tracks went for about $6,000 or so. (And that was in 1980 dollars which equates to about $7600 and $15,235 respectively in 2005 dollars !) Today, 1/4" professional decks can be had on eBay for about $350 to $500 for a mint one that occasionally turns up every several months. Be prepared however, to take it apart and remove the old dry grease, re-lube & re-belt it no matter what the ad gloriously claims. "PB Blaster" (available at any good automotive store) is a great solvent for removing the old dry grease. Just spray some on a "Q-tip" and have at it !....... Be warned though....... it's also an effective solvent on many plastics and any rubber components. Replacing the old drive belt (which are readily available) just on general principals, would also be a nice touch while you have it apart. Once cleaned, lubed and de-magnetized, you'll have to check head alignment/azimuth and adjust the equalization for the tape you intend to use. For less than several hours of effort, you'll have a sweet, almost "new" reel to reel machine...
Half Track
Often referred to as the "broadcast standard" due to its popularity in the broadcast industry. The format uses half the tape to record both tracks & thus its name. Therefore, there's two channels, recorded simultaneously in ONE direction. (There is no "B" side) Since the format uses the entire area of tape to record the the two tracks, it offers the best sound quality. As tapes age, the audio is far less affected by oxide dropouts.
One drawback of the 1/2 track, is that there is no additional channel upon which to record the SMPTE time code. For many users who merely demand high quality recording, it was not an issue.
Quarter Track Stereo 
Visually similar to a half track in the sense it has just two level meters, the similarities end there.
This format uses a quarter of the tape to record a single track,
and thus its name. The track use is staggered however. In the forward direction,
tracks 1 & 3 are recorded for stereo. Upon flipping the tape, tracks 2 & 4 are then
recorded in the reverse direction. More expensive machines incorporated a reverse
function whereby the head tower was stepped down or electronically switched to the alternate tracks,
thus negating the need to "flip the tape"
Quarter Track Discrete
- 4 Track
This layout or use of tracks allows 4 track
simultaneous recordings to be made in one direction, utilizing all the tape. Thus
there is no "B" side. The advantage of this layout is that 4 separate musical instruments
could be recorded independently and the tape later used to "mix down" the channels
into the final stereo or even mono mix if desired. Like its quarter and half track
counterparts, there is no provision for a SMPTE channel.
Quarter Track SMPTE
This is really not a separate format, as the machine is really a 4 track discrete. It's just a matter of how each channel is utilized. To enable SMPTE time code to be recorded, something had to "give. Thus channels 1 & 2 were assigned the left and right channels respectively, and channel 4 was assigned to the Time Code. To prevent and cross track interference from the time code which was usually recorded "hot", plus since it was a harsh distinctive sound whereby the least amount of crosstalk could be heard, channel 3 was not used and thus served as a guard band.
The first audio tape machines were open reel to reel, and evolved into a wide number of tape widths and track configurations.
The first being the Ampex Model 200 released in 1948 and purchased by ABC for the recording of delayed broadcasts. By 1954, Ampex began marketing the first multi-track machines, and the stage was set for the switch from Dictabelts & Wire Recorders to magnetic tape.
Open reel to reel was the predominant format, from audio tape's inception, to the early 1980's, when digital started making in-roads.
Popular tape widths ranged from 1/4 inch to 2 inch, while track formats ranged from 1/4 inch mono to discrete 32 track analog 2 inch tape - and almost anything in between ! Tape speeds ran the gamut... 15/16, 1 7/8, 3 3/4, 7 1/2, 15 and 30 ips.... Though 1 7/8 to 15 ips are the most common. 15/16 ips was normally relegated to the 24/7 of police and military recordings of phone transcriptions and shortwave interceptions.
1/4" consumer machines typically used anywhere from 1⅞ to 7½ ips, while 15 & 30 ips speeds were normally found only on the professional machines.
Early home and educational classroom recorders such as the Wollensack most of us remember from our school days of the 50's, were all reel to reel. The transport system was both simple and highly reliable. As the consumer moved on to the "no thread" - "idiot proof" cassette and cartridge systems to come, the professional community stayed with the open reel to reel. Since much early editing was done literally by "Cut and Splice", open reel had a distinct advantage, and most early professional decks came with a built-in splicing block. Advancements in solid state electronics and motor servo systems made these transports a dream to work with.
Various open reel formats remained the professional's transport of choice from it's early inception, to it's slow demise, when it was retired in favor of the newer evolving digital formats.
So..... You found an old reel and wondering how much may potentially be recorded on it ?
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Time Chart for Open Reel-to-Reel Analog Audio Tape (Approximate) |
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* Reel Diam |
* Tape Length |
One Direction |
2 Directions |
Two Directions |
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| 1 7/8 ips | 3 3/4 ips | 7 1/2 ips | 1 7/8 ips | 3 3/4 ips | 7 1/2 ips | 1 7/8 ips | 3 3/4 ips | 7 1/2 ips | ||
| 3" | 300 ft | 30 min | 15 min | 7.5 min | 1 hour | 30 min | 15 min | 2 hours | 1 hour | 30 min |
| 5" | 600 ft | 1 hours | 30 min | 15 min | 2 hours | 1 hours | 30 min | 4 hours | 2 hours | 1 hour |
| 5" | 900 ft | 1.5 hours | 45 min | 22 min | 3 hours | 1.5 hours | 45 min | 6 hours | 3 hours | 1.5 hours |
| 7" | 1200 ft | 2 hours | 1 hour | 30 min | 4 hours | 2 hours | 1 hour | 8 hours | 4 hours | 2 hours |
| 7" | 1800 ft | 3 hours | 1.5 hours | 45 min | 6 hours | 3 hours | 1.5 hours | 12 hours | 6 hours | 3 hours |
| 7-10" | 2400 ft | 4 hours | 2 hours | 1 hour | 8 hours | 4 hours | 2 hours | 16 hours | 8 hours | 4 hours |
| 10" | 3600 ft | 6 hours | 3 hours | 1.5 hours | 12 hours | 6 hours | 3 hours | 24 hours | 12 hours | 6 hours |
* Some tape is thinner and thus more can be spooled on the same diameter size reel.
One question we're constantly asked, is about the difference
in the reel spindle sizes......
The larger professional machines held large heavy metal reels & were capable of shuttling tape at lightning speeds. Professional machines recorded at 30 ips or about 150 feet of tape/minute. Broadcasters and production houses had deadlines to meet, and demanded machines that could "Move Tape" in every sense of the word ! Metal reels were used as opposed to plastic, as plastic reels have a tendency to shatter at high rotational speeds. Should a reel come loose, a plastic reel would disintegrate, shooting plastic shrapnel about the studio, so metal reels were much safer for this reason.
Keep in mind that on professional machines near the end of tape in a fast forward or rewind mode, the reel with the less tape will seem to be approaching gas turbine rpm's. The last thing needed was to have a heavy reel break free and commit suicide by careening through the studio - hell bent for total destruction of anything either too stupid or not fast enough to get out of it's way - until it's wildly untamed kinetic energy was dissipated. The reel would randomly ricochet off anything encountered and could easily "climb" equipment racks as high as the ceiling and sometimes repeat the mayhem several times before it exhausted itself or became imbedded in a nearby wall. The damage (depending upon what it hit) could be substantial - especially with large heavy one or two inch reels..... not to mention dangerous. Quite a spectacular if not expensive event..... (Having witnessed such excitement, & being forced to "dive for cover", all this is not an exaggeration...) Being an audio recording engineer in the "good ole days" was sometimes dangerous work....
Enter the NAB (National Association of Broadcasters). Since the manufacturer's didn't seem all too concerned about the problem or couldn't agree amongst themselves as to a common standard solution, the NAB thankfully stepped in and established the standard for professional reel hubs. Since the broadcasters were the primary buyers, the manufacturers finally listened (albeit, mostly out of economic "bottom line" concerns) and astutely became quite agreeable with what the NAB demanded. An adapter would slide over the existing spindle on smaller 1/4" machines (so standard non-NAB reels could still be mounted) and be locked securely in place. The NAB type reel then was tightly secured to the hub by a simple yet effective rotating screw lock mechanism. The NAB hub adapters were an option (albeit a necessary one) on some machines, though larger half inch, 1 inch and 2 inch machines (owing to the much greater damage they could inflict) had only NAB type hubs and were not removable. Not only was it a safety issue, but it also at the same time set a standard size for industry wide interchangeability........... Before purchasing a set, make certain your machine supports them, as the existing spindle must have a locking mechanism to secure the adapter.
Now you know !
- SoundtapeIn 1958 RCA developed an audio cartridge system known simply as the Sound Tape Cartridge.
It was one of the first attempts at taming unruly reel to reel audio tape and making it transportable.
The cassette housing appears more as an over-grown standard audio cassette, measuring 5 x 7 1/8 x 1/2 inches. Tape speed was either 3.75 ips resulting in 30 minutes of audio on 1/4 inch tape or 1 7/8 ips selected by a small lever. The speed selector lever merely re-directs & "jumps" the drive belt from one pulley to another. Simple and a bit crude perhaps, but it works !
The recorded tracks could be selected via a switch that selected track "A" or "B" per each side, so it is in fact a 4 track format. Most machines were 4 track mono, yet later higher end models were stereo. One shortcoming of the machine that was endemic to many early audio formats, is that there is no fast forward. To fast forward, you flip the cassette over and do a rewind, then flip it back over to continue. Depending on the machine, you could have 2 separate mono tracks per side or a singe stereo track .
The recorder features a built in speaker, line level inputs and outputs, provision for an external mic and was all vacuum tube technology. Interesting to note, is the wide use of plastic for the main exterior body of the machine. Plastics were just coming of age...
RCA Records made an early attempt at making this a popular pre-recorded music format. However it turned out to be a major "Flop" in that regard. The format did find it's way into homes by 1960, as an early mono cartridge format for recording family history. A lot of priceless family recordings have been made on this early cassette format...
NAB
Cart Tape (1959)Introduced in 1959 by Collins Radio, the cart tape format was designed for use by radio broadcasters to play commercials, bumpers and announcements.
Cart Machines were NOT a consumer format ! 8 Track cartridges though similar in size, will not play in a cart machine. In fact, the carts more resemble the early Muntz 4 track stereo cartridges where the pinch roller resides in the machine and not in the cartridge. Note also that the cart tape format offers better fidelity than the later to follow 8 track cartridge, owing to it's wider track pitch & 7.5 ips speed.
Prior to the Cart Tape format, commercial spots and bumpers were often recorded on open reel half track machines, which always necessitated manual threading and cueing..... both time consuming processes, that were prone to operator errors & resulting mis-cues (No offense: but DJ's & radio personalities were not often noted for their technical skills - except perhaps in the early days of broadcasting).....
Mis-cues often resulted in the dreaded "Dead Air" AND almost always; in a "pissed off" client - - - demanding a free re-airing of his spot without it being "butchered".
Though no one in the broadcast industry will openly admit it, the ONLY reason for programming, is to entice people to listen or watch the commercials that ultimately "pay the freight". All programming including the alleged "News", sports, movies, dramas, comedy's, Talk Shows, sit-coms etc etc etc, are simply there to fill in the "black holes" between the commercials. In the radio industry, it was the "Cart Machine" & what advertising they could sell to play on it, that ultimately determined the success or failure of a station.
Anyways, the time consuming threading/cueing process of open reel audio tapes, meant that usually a technical director was required to deal with such mundane tasks to free the DJ/Talk host to do what he does best - - - thus necessitating at least two personnel to pull off even a simple broadcast. With the advent of the Cart Machine, even a DJ/Radio personality working alone on a Sunday morning for example, could do it all - especially in small markets where the budget for a technical director was simply out of the question... Thus in most cases, the burden of playing the proper commercial/bumper without mis-cueing, rested with the DJ/Radio personality. Like an answer from Heaven itself, the cart tape solved all those issues, by eliminating those two time consuming & error prone steps. Now a DJ merely "popped" a cartridge into the machine which would cue itself to the exact starting point ,and he'd merely hit "start" when ready and adjust the levels on the board if need be ! No threading - no manual cueing: ...... all he had to do was to "hit Start" ! The entire operation was now virtually "idiot proof" ! (no insult intended, as I have a GREAT ADMIRATION for ANYONE that can DJ or host a live broadcast ! ................. God knows, I certainly haven't the verbal/communications skills.....)
Then for the next 30 or 60 seconds, all they'd have to do, was to either "cue up" other carts .......... "Veg"........... figure out what to say next........ or personally reflect on the meaning of life ! (whatever....)
The first machines were one track mono used extensively for AM radio broadcasts, such as this fully restored monophonic Tapecaster X-701RP as shown on the right....... but stereo machines were soon to follow. Those played 2 track stereo on 1/4" tape at 7.5 ips. Both included a separate 1 kHz cue track to mark the location of program material. Development of the format led to secondary cue tones of 150 Hz and 8 kHz which were used to trip dedicated internal relays that could be used for external device control - even computer control !
Many Cart recorders did not have full erase heads, necessitating the use of a bulk eraser, should the tapes be targeted for "re-cycling" for other uses. Some cart bulk erasers also incorporated "splice finder" logic, to aid in quickly locating the endless loop splice, which by default, was usually always the cue point.
In general, cart machines were "built like tanks"..... (They had to be ! - as they were in constant use 24/7). Because of the high mechanical reliability and audio quality demanded by broadcasters, the cart machines were not "cheap".... averaging $2200 per player and $3500 for a player/recorder (Note: and that was in 1980's dollars !)
Though still in use today, most stations have switched over to computerized digital technology for day to day operations.
But when windows inevitably crashes, the "trusty ole" cart machines are still retained by some stations, standing by in the ready ! .... They may be antiquated mechanical "beasts", but they don't "Crash", and are capable of reproducing excellent quality audio when properly maintained........ (and as the old motto goes in the broadcast industry) ..... ANYTHING is preferable to "Dead Air"
Though the hay day of cart machines is long past, Cart Machines are still being manufactured to this day.......
Not bad for a technology that has spanned some 47 years (and still counting) as of 2007 !
"Though the name played on the "Cart" terminology, it wasn't really a cart based unit at all. This was perhaps one of the first moves away from analog tape based carts, to the digital domain. The Sonifex DX-300 used 3 floppy drives. The top drive could be used as either the player or recorder, while the two lower drives were dedicated for use as players only. The Discart had all the Cueing functions like a tape, but unlike tape, cueing is almost instant, owing to the relatively fast seek time of the floppy drive. Though the audio was stored as digital files on floppies, the format was proprietary to the unit and cannot be read directly on a PC. As such, the unit performs it's own formatting and verifying functions . The unit could record up to 37 seconds of CD quality stereo audio on a 2mb floppy
The unit recorded in high quality stereo with balanced audio in and out XLR connectors. There are also provisions for a keyboard, 9 pin digital in/out, RS-232 remote for computer control, BNC Datalink and conventional remote connections.
Though this machine came along much later in the Cart Machine timeline, we ended up placing it below the original cart tape machine, to show the evolution.
The
Sanyo Micro Pack 35 also sold under the Channel Master brand name as a Re-badged
Sanyo, was an early format portable dictation player/recorder for the busy executive
of the 60's. The tape
was
housed in a transparent cartridge measuring 2.6 x 2.9 x 1.9 inches and slid
easily into the bottom of the recorder. What's unique, is how the tape was stored
on two reels residing atop one another, keeping the cartridge compact.
An exclusive innovation of the era, was a variable speed control which was possibly one of the first vari-speed portable dictation recorders produced. The entire machine is ruggedly built and quite heavy, though the dimensions of the unit are a mere 3.5 x 6.5 x 1.25 inches. Solid heavy gauge metal throughout, there's little doubt that the unit would probably survive being driven over by a car ! (try that with a modern device .......)
The Micro Pack used what's called a rim drive mechanism. Instead of a conventional pinch roller/capstan system, the Micro Packs used a single pivoting motor with extended shaft that entered thru the side of the cartridge,. There it made contact with a rubber ring built in to the outside circumference of each reel to provide the drive. The drive motor could be pivoted up or down (play or rewind) by the mechanical linkage of the function switch - an incredibly simple and also reliable design. Course the tradeoff was that there was no fast forward, and rewinding was somewhat slow.
A microphone is not built in, and an external mic is required to record. There is however, an earphone plug. A meter serves as both a recording level indicator (no auto levels here !) as well as a battery meter. There is no provision for an ac adapter..... Too bad, as this little machine is a bit power thirsty. A single twist control selects between rewind - stop - play and record (there is no fast forward). To fast forward, you'd have to flip the cartridge over and rewind - then flip it back over again ! The standard cartridges held approximately 15 minutes on each side.
The unit is powered by 4 AA batteries and the tape would record up to an hour per side. Though only mono, the audio quality is surprisingly good (assuming a quality microphone was used to record) owing to a good quality 2 inch built in speaker.
za
Compact Cassette (1962) - The Standard Audio Cassette - Quad Compact Cassette
Ironically, the standard audio cassette still
in wide use today, was never intended for wide usage, but instead was originally
developed by Philips in 1962 for use in their new line of dictation machines. However
it's compact size, reliability, low manufacturing costs and Hi-Fi stereo capability,
ultimately led to wide market acceptance. Popularity of the format, surprisingly,
was not immediate. Though 8 Track cartridges were not to be introduced for another
3 years since it's introduction, it wasn't til the early 70's, that the compact
cassette became the predominant consumer tape format.
The format employed 1/8-in. tape with 4-tracks running at 1-7/8 ips, initially allowing 30 or 45 minutes of stereo music per side, until longer tapes became available .
The original tapes were Ferrite (Fe2O3), but later, Chromium Dioxide (CrO2) and other metal particle formulations were used in order to greatly improve sound quality. Chrome tapes had different bias frequency requirements, requiring more sophisticated recording equipment. Later machines employed various noise reduction technology, though in later years, Dolby became the most popular by far.
Quad Compact Cassette - DBXThough really a different format; so closely associated with the standard Compact Cassette, that I ended up placing it here, so as to more easily compare the differences....
Though the vast majority of consumer decks were stereo, Tascam as well as a few others, offered a Professional 4 track discrete machine that allowed 4 separate discrete tracks to be recorded at once ! Introduced in 1983, the Tascam 234 Syncaset offered high quality 4 track discrete recording that included on-board DBX noise reduction. Many claimed that with DBX & being recoded at twice the speed of a standard compact cassette, it's fidelity rivaled that of many open reel machines. Quite an achievement for the time (and with DBX built in !) .... Unlike standard compact cassette machines, the professional Syncaset recorded as well as played back at twice the speed of a standard compact cassette at 3.75 ips, for much improved audio fidelity and reduced noise. Unlike 2 channel stereo, there was no cassette "B" side, as all 4 tracks were recorded independently at once in one forward direction. Though the 4 track discrete Compact Cassette is a really a different format, the track layout is in fact identical to that of a standard compact cassette. The only difference is that the 4 track discrete deck employs 4 heads in the record/playback head tower and all 4 tracks were recorded at once, in just one forward direction. TASCAM later came out with newer similar products such as the 424/424 MK-II that utilized the much newer Dolby noise reduction system, however these were not compatible with those that were recorded earlier using DBX encoding... Though the 424 is widely available today, the earlier 4 track DBX discrete machines are now quite rare...... (at least well maintained working ones anyways...).
DBX Side Note:
Attempting to play a Quad DBX in a standard tape player, will result in the content sounding very "low and slow" - since it's being played back at literally half the speed at which it was originally recorded.... Even compensating for the speed difference, DBX encoded tapes will sound "tinny" with poor fidelity when played on equipment that does not employ DBX. Put another way: DBX and Dolby are NOT compatible.
Initially, the standard compact cassette found wide use in archiving vinyl records. Though the CD put an end to it's 20 year reign, it was by far the most popular of all the audio formats to date. The compact cassette is not dead yet though.... Most homes currently have at least one of these machines with a large library of tapes stashed away in closets . They are still widely used in heavy over-the-road trucks, due to their inherent immunity to shock and vibration. My guess is that the compact cassette will still be hanging on in another 20 years (or at least until the old tapes finally disintegrate or new tapes are no longer available).
Over 40 years since it's initial introduction, and it's still being widely used... Not bad for a format initially only intended for monophonic Dictation.....
"Who'd a thunk"........
Not even sure where to place this; but I suppose something should be said of the various noise reduction schemes employed by many of the various equipment manufacturers to minimize the effects of tape hiss. This is not a comprehensive discussion, as there are plenty of excellent references that delve into the finer details, but this will give a brief overview.
With magnetic tape, comes tape hiss. Discreet magnetic particles no matter how fine being pulled by the heads will result in a certain level of tape hiss.... It's a simple fact of life. This "hiss" is uniform, and although at a low level, it is still objectionable. The energy distribution of the "hiss" is normally right in the middle of the higher frequencies of the recorded material, resulting in a lower signal to noise ratio in the low level "brighter" sections of the material. Since as we stated that tape hiss is a fixed given, the only "out" is to increase the high end frequencies of the recorded material so as to improve the signal to noise ratio (which is just a fancy way of saying that we intended to "drown out" the tape hiss by recording the material louder. It's more than just turning up the recording level and recording everything "hotter" however. To preserve the dynamic range, one must do it somewhat selectively by boosting only the frequencies or sections in a way that will not introduce clipping.... The 3 main techniques for this are Pre-Emphasis/De-Emphasis, DBX & Dolby.
What follows are the basic differences written as simply as I know how (at least without over-simplifying it)..
Pre-Emphasis/De-Emphasis
The basis of the noise reduction techniques... in fact, DBX and Dolby just take it to the next level so to speak.... Pre-Emphasis may be thought of as using an equalizer or glorified tone control if you will, to record the material with a lot of extra treble or high frequency boost. Doing so, increases the signal level of those high frequencies, which yields a greater signal to noise ratio. The desired high frequency material is now at a greater level than it otherwise would have been, and is recorded as such to tape. To put it another way, we boosted the level of the signal that got recoded to tape. The hiss in a sense has now been "drowned out" by the much louder recorded material. Thus we can say the recording now has a much greater signal to noise ratio and we have thus "beaten" the hiss problem... That phase is called Pre-Emphasis.
Only downside, is that if nothing is done upon playing the recording back, it will now sound overly bright or "tinny"...... To restore the frequency balance, we now must attenuate by the same EXACT equal amount the same frequencies we boosted in the pre-emphasis stage. This is called De-emphasis, and restores the material to it's normal fidelity. End Result: Tape hiss has been greatly reduced !
Pre & De-Emphasis is pretty simple. It takes somewhat of a "global" approach.... Low volumes & high volumes are treated all the same.....
DBX ®
Most early 1" type C Video formats used DBX as well as TASCAM's professional line of audio equipment. DBX also uses pre-emphasis and de-emphasis but adds 2:1 compression across the full spectrum. By compressing, the entire program can effectively be recorded even "hotter" without clipping. By doing so, some pretty impressive signal to noise levels are achieved and recorded that way to tape.
On playback, the material is now equally de-compressed (expanded) as well as de-emphasized, thus restoring the material to it's natural fidelity.
Since DBX pushes Pre-Emphasis and compression to the max, achieving an exact countering de-compression and de-emphasis, requires high end studio equipment that has very repeatable accuracy, such as usually found in the large open reel formats. There is not much room for error when pushing the limits !
Later in an attempt to break into the evolving consumer market, DBX Type 2 was developed for incorporation into cassette formats.
The difference you ask ? .... DBX Type 1 could achieve almost unbelievable reductions in tape hiss. - on the order of 30 dB. Again: to do so required very repeatable accurate transports to allow exact de-emphasis and de-compression to restore the material to it's exact fidelity.
Since cassettes had none of the repeatable accuracy characteristics of an open reel deck, DBX could still be used, but the amount of emphasis/compression/expansion was reduced to account for the "sloppier" cassette transports. This was called DBX Type 2. It used the same "strategy" as that of Type 1; just that it didn't boost and then attenuate as much....
Dolby ®
Like DBX, Dolby uses pre & de-emphasis. Unlike DBX, Dolby realized that in loud sections of the material, the signal to noise ratio was already more than acceptable... No sense having to do anything with the loud passages, as the noise was unable be be heard over the "din" anyways. In those sections of the material, the signal to noise ratio was already more than adequate... Where noise (tape hiss) became noticeable to the listener, was in the quiet sections.
Where Dolby differs, is that Dolby uses pre-emphasis/de-emphasis only for the quiet sections. Since only the quiet sections are processed and compression/expansion not used at all, the necessity of exactly replicating the exact de-emphasis correction on playback, is not nearly as critical. .
The end result: Dolby averages around 10dB in noise reduction. Still pretty good, but a far cry from DBX's 30 dB....
There are various "flavors" of Dolby such as Type B & C (the most popular to consumers) as well as a few others. Without delving into it, the main difference between B & C are the cutoff points below which nothing is processed (400 Hz for Type B and 100 Hz for Type C).
Summary:
Today, DBX ® is relatively rare. Most consumers never even heard of it. The question then becomes; if DBX achieves 30 dB of noise reduction and Dolby on average only 10 dB, then why did Dolby ® become so recognized and adopted by most of the consumer equipment manufacturer's ???
Part of the reason is that DBX simply got "out-marketed"... But again, that's only part of the reason...
The others are more pragmatic...
Making a good DBX encoded recording, means paying close attention to the recording levels. Since DBX uses a 2:1 compression, DBX will ill tolerate recording levels going much above 0 on your VU meter. Not only is transport stability critical, the recording engineer had much less "maneuvering room" in setting proper recording levels. Even in the case of DBX Type 2, Dolby was still easier and more forgiving for the consumer to obtain good results.
Dolby A, B & C was much more forgiving of technical shortcomings (both in equipment & operator). I suppose one could say it was more "idiot proof"....
Personal opinion; Since Dolby didn't resort to more sophisticated (read: expensive) compression/expansion techniques, the Dolby circuitry was also dirt cheap to manufacture.
In any heated battle between quality and cost, lower cost almost always wins...
The stereo 4 track cartridge was the forerunner of the 8 track cartridge system. The format was actually developed in 1954 by George Eash at Muntz Stereo in Van Nuys, CA. Muntz took up the call and began marketing the 4 track system in 1962.
Aside from the obvious differences in the number of tracks and track spacing, the only difference between the 4 track cartridge and the 8 track in terms of physical dimensions, was that the 4 track cartridge did not house the rubber pinch roller inside the cartridge, but rather the pinch roller was located in the machine. Subsequently, there is an additional hole in the cassette shell where the machines' pinch roller fits in to. Thus although the same size, a 4 track cartridge will NOT play in an 8 track machine.
Though a 4 Track cartridge will fit in a broadcast Cart Machine and play (of sorts), Cart machines were either full track mono or stereo half track. Also 4 track cartridges were recorded and played at 3.75 ips, while the standard speed for Cart Tapes ran at 7.5 ips.
Unlike the soon to come 8 track system, there is no auto-switching between tracks. Track switching is performed manually.
Fidelity of the 4 track cartridge was very good for it's day and is similar to that of the 8 track.
By 1970 the 8 Track was King, and the Compact Cassette was quickly gaining ground. Production of the 4 track cartridge was thus discontinued.
Orrtronics Auto-Mate Cartridge (1962)
Herbert Orr thought he had a better idea for an endless loop cartridge. The Auto-Mate Cartridge sold fairly well in the mid 60's shortly after it's introduction and was even picked up by several major labels as a means of distribution. In the sound quality department, it offered slightly better fidelity than Bill Lear's 8 track. Yet the market place is a fickle thing, and Bill Lear was riding the wave of his highly successful Learjet Business aircraft. Consequently, the 8 track won out and the Orrtronic Auto-Mate was abandoned after a short lived success in the mid 60's.
A
consortium consisting of Ampex, Lear Jet, Ford, Motorola and RCA Records joined
forces to create the "Stereo-8"
format tape players. The initial target market called for a cartridge system that
could be added as an automotive luxury option. "Stereo-8"
is the format's actual correct official name, though later it became far better
known as the "8 Track" Cartridge.
The format uses 1/4 " tape divided into 8 tracks and recorded at a speed of 3.75 ips. The audio is recorded and played back in 2 channel stereo. Four stereo passes yields the 8 tracks and hence it's name. The tape is stored on only one endless loop reel, and tape is supplied from the center of the reel. For the most part, it worked ok, but was sometimes prone to jamming... The tape was notorious for binding up after constant use, as the lubricating agent was worn away.
Magnetic sensing tape marks where the tape is spliced together to form the one large loop and subsequently the beginning of the tracks. When the metallic tape strip is detected by the sensor, a solenoid driving a latching mechanism, steps the head tower assembly down to the next group of stereo tracks. At the end of track 4, the tower assembly latches the head tower back to the top. Track switching invariably made a neat distinctive "cher-clunk" sound, endemic to the 8 track. Since the tape is endless, the process goes on ad-infinitum.
Interesting to note that this was the first audio player of it's kind to employ mechanical "automation" for continuous play as a standard feature. The head tower latching mechanism was quite ingenious, and it's head positioning method, surprisingly accurate, considering the mechanical menagerie of gears & cam assembly necessary to make it work. Early units were players only, intended for automotive installations. Home recorders were soon added to the product line to allow recording of personal material.
Audio quality was actually quite good by the standards of the day, and the 8 track became an instant hit. The 8 track was actually the first truly successful format for commercial distribution of recorded music on tape, until it was replaced by the smaller compact cassettes which slowly gained in popularity. It's popularity in the automotive industry alone, sparked the development of much higher quality speakers found in cars & later trucks.
What's unusual, is the fact that the format was first used as part of an automobile's sound system, and was only later widely adopted for use in the home. In all other cases, the opposite is true.
Though initially intended only as a two channel stereo format, it's 8 separate tracks offered an excellent opportunity for the recording all 8 tracks simultaneously at once (known as discrete track recording). Though the format was fully capable of recording up to all 8 tracks at once in one direction, for reasons unknown, no manufacturer ever made a deck to fully utilize its 8 track discrete potential - most likely due to a very limited market. A few manufacturers did go "half way" however, with the maximum number of discrete tracks capable of being recorded at once being 4 tracks. Four track discrete format tapes (quad) can still be found on eBay, however the decks to play them are becoming somewhat more scarce. It's interesting to note that this was the first successful 4 track discrete format to find it's way into the hands of the consumer. I suppose you could say the 8 track quad was the first commercially successful "Surround Sound" system !
In 1966 the dominant formats were the 4 track reel to reel and 8 track cartridge systems. Both were large, cumbersome and not by any stretch of the imagination, truly portable.
Enter "Playtape".... a neat little machine that played pre-recorded cartridges that was both light and portable. It was billed as a replacement to the transistor radio (though it was actually more of an alternative than a replacement).
The small cartridges measured 2 3/4 x 3 3/8 x 1/2 inch and
housed 1/8 inch tape. It was only a two track stereo system that would play in only
one direction, but the cartridges were wonderfully small as compared to an 8 track
cartridge. Their small size made for a compact and power efficient player. The tapes
ranged from about 8 to 24 minutes in length. Sears sold the players for $19.95,
and they moved like hot cakes. Playtape was an instant success ! Now for the
first time, you could take the music YOU wanted to listen
to anywhere ! ..... The dawn of "Micro-miniaturization" was at hand !
In today's' terminology, the Playtape could be considered the "i-pod"
® of the 60's......
So successful was the format, that by 1968 there were already over 3,000 titles recorded on Playtape.
There are a number of web sites dedicated to the Playtape - it has somewhat of a cult following ! (and I mean the word "cult" in the kindest way !)
The Elcaset format was introduced by Sony in 1977. Though marketed as a consumer
format, it was intended as a platform to offer open reel to reel quality with the
convenience of a "compact" cassette.
Cassettes for the Elcaset, were somewhat larger than today's compact cassette... The cassette measured 6 x 4 1/8 x 11/16 inches approx. Kind of like a standard compact cassette on steroids !Considering it's competition were the much larger open reel machines, the design was very compact by comparison !
Note the size difference between the Elcaset and a standard Compact Cassette.
Though not the quality of current digital formats, it rivaled standard open reel recordings of the day made at 7 1/2 ips. Part of the reason for the high quality at the time, was the tape formulations supported (such as "new" high bias metal particle) as well as supporting the "new" Dolby noise reduction technology. Only the relatively high cost of the decks, resulted in the format not being widely accepted by other than true audiophiles.
Compared, to even current day standard high end compact cassettes, the Elcaset offers superior fidelity !
For a technology introduced in 1977, the Elcaset was ahead of it's time.
Sony PCM-F10 (1978) - PCM-F1 (1981)
The Sony PCM-F10, though not the first digital stereo recorder, was the first to make it truly affordable.
PCM is the acronym for Pulse Code Modulation, which is the recording technique for recording digital data on tape. To achieve a low cost, the PCM encoder/decoder used a standard Betamax Video deck, though any video deck would usually work.
The initial system was somewhat bulky and by 1981, Sony released the second generation called the PCM-F1 which reduced the processor size substantially. Quality (although not up to current standards) was actually quite respectable. The analog to Digital and Digital to analog (ADC and DAC) chips developed for the F1, soon found their way into the very first CD players.
Considering Sony's $2500 PCM system was only about 1/10th the cost of a dedicated digital recorder at the time, the F10 & F1 became milestones in the start of the digital revolution.
The technology incorporated into the PCM-F1, paved the way for the soon to come DAT machines.
Specs
| Channels | 2 |
| Sampling Freq | 44056 Hz |
| Quantization | 14 or 16 bit linear |
| Frequency Response | 20-20,000 Hz ± .5 dB |
| Harmonic Distortion | less than .0007% (16 bit) |
| Dynamic Range | Greater than 90 dB |
| Channel Separation | Greater than 80 dB |
| Error Correction | CRC & Parity |
| Dimensions | 8.5 x 3.25 x 12.1 |
Developed by Philips and Sony in Japan, the audio CD in the form we know it today, was released in the UK in September, 1982. The CD was highly marketed, but slow to gain wide market acceptance, owing to it's high initial cost. However, the sound quality and portability of CD's was undeniable, and outweighed the high cost for many consumers. With the efficiencies of mass production, prices plummeted, and the CD became the medium of choice by the end of the '80s.
The CD ultimately became the final "nail in the coffin" for the long running reign of LP records. Skips, crackles, pops. wow, flutter, surface noise and worn grooves all part of the vinyl "experience", was now a thing of the past.... So cheap and reliable is the media, that software companies began distributing software on the discs. Companies such as AOL
® did numerous mass mailings of their on-line software. Many of these CD's were found to be quite useful for applications ranging from beer coasters to "anti-wobble" table leg adjusters - and almost anything imaginable in between....... The CD had a versatility greater than anyone could have ever possibly imagined !The CD quickly became another cornerstone of the current digital music revolution. Later product development led to the CD-R and CD-R/W formats for both audio and data. Now you could "burn your own" !
Today's higher sampling rates and bit depths, have resulted in improved fidelity. Yet owing to the world-wide huge established base, the CD with it's 44.1 kHz sampling rate at 16 bit depth still reigns as the audio "king of the hill" for music distribution.
(So popular is the standard CD player, that we decided not to include a picture - there are literally hundreds of models !)
Introduced in 1987 for the professional studio market, digital audio tapes quickly claimed the high ground in professional recording industry circles. DAT's never garnered consumer market penetration because of the high cost of DAT players. However, they remained a mainstay of the pro-audio world because of their relatively low price and digital storage capabilities.
Our own government was a major contributor to the DAT never making in-roads into the consumer market. Bowing to corporate "pressures" (and not surprisingly, that of the voters who put them there) a stiff tax was added to each DAT tape sold. The collected funds were used to "compensate" the powerful music industry for songs that could possibly be pirated. Our constitutional doctrine of "innocent until proven guilty" sadly and frighteningly, got tossed out the window. Most insiders "in the know", view it as just another case of flagrant "corporate welfare" in operation at it's best (at taxpayer expense), supported by the best politicians that money could buy ..
Not to be beaten, the DAT manufacturers quickly re-designed machines that could utilize less expensive computer-grade DAT tape to circumvent the steep tax. The damage to the consumer marketplace however, was done and sadly never recovered.
The DAT system design more closely resembles a helical scan VCR than a traditional reel to reel or cassette based recorder. Digital audio is recorded much like video, using a helical scan FM technique. Note also that DAT cassettes are nicely compact !
The Fostex D-5 shown here, has analog, digital as well as optical inputs and outputs. Unlike MD, CD-R and most other digital formats, DAT recorders are regarded as a professional digital format used for original mastering and therefore bypass the SCMS (Serial Copy Management System), thus allowing multi-generation, loss-less digital recordings.
The digital age was at hand !
Released in 1991, the first ADAT machine took the recording industry by storm. An 8 track high quality digital recorder with 16 bit depth and 48 kHz sampling - all in a compact footprint. The ADAT's use standard S-VHS cassettes that allow up to 60 minutes of better than CD quality recordings to be made. Initially, the first machines had an approximate $4,000 street price, but compared to their earlier 8 track open reel counterparts priced about the same for a studio grade machine at the time, the ADAT won the quality battle hands down. The current era of Multi-track digital recording had begun !
Later incarnations of the product line, resulted in 20 bit sampling.
Like it's soon to come Tascam competitor (The DA series), the ADAT's can be slaved & synchronized together and the amount of the channels you can add is limited for practical purposes by the number of machines you can afford (at least without ending up in divorce court).
One major advantage of the ADAT deck, is the 1/2" S-VHS tape format it uses. The much wider tape is much less susceptible to edge damage than Tascam's 8mm format. The much lower data density per square mm owing to the larger tape, results in increased reliability and longevity of the tape.
Specs of the XT-20
| Transport: ADAT Rotary head digital recording Type I (16-bit) and Type II (20-bit) S-VHS cartridge |
Recording Format ADAT Rotary head digital recording Type I (16-bit) and Type II (20-bit) S-VHS cartridge |
| Tape Format:
Heads: 4 (2 Read, 2 Write); Read before Write |
Approximate Recording
Times: ST-60: 22 minutes ST-120/SE-180: 40 minutes ST-160/SE-240: 54 minutes ST-180/SE-260: 62 minutes |
|
Fast Wind Rate: 40 x play speed (Threaded) |
Number of Audio Channels:
Eight Discrete |
|
Record (A/D):
over-sampling, single converter per chan. |
Playback (D/A):
over-sampling, single converter per chan. |
|
Sample Rate:
44.1 /48kHz, Selectable |
Vari Speed Range: +100/-300 cents (48kHz), ±200 cents (44.1kHz) |
| Frequency Response: 20Hz– 20 kHz, ± 0.5dB | Dynamic Range: 102 dB, A weighted in 20-bit mode |
| Distortion: 009% THD+N @-1 dBFS in 20-bit mode | Channel Crosstalk: Better than -90 dB @ 1kHz |
| Wow and Flutter: Un-measurable |