Audio Restoration

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Services - Transfers and Duplication

Transfers - Wire Recording - Vintage 78's - Edison - Pathe' - Little Wonders - early Victor and many others

We transfer from almost any video or audio format to CD.  We handle the early vintage 78 discs to wire recordings and just about anything in between. We can also transfer to any other supported format including even broadcast, home or even vintage & obsolete video formats.

To learn more about wire recordings:    Click here... 
To learn more about vintage 78 discs:    Click Here...

Audio Restoration Philosophy

Our philosophy is to employ the minimum amount of filtering required to reduce significantly reduce noise levels without the audio becoming "muddy".   (Audio processing almost always involves a tradeoff between fidelity and noise).  At your request we can deviate from that philosophy by employing more aggressive techniques where warranted.  We can also enhance the original by heterodyning up mid-range frequencies to the high end (audio exciter), adding "warmth", increasing "hardness", equalizing, de-clipping, compressing or expanding.

Though digital processing can perform some near miracles, it does have it's limits.  Records with excessively worn grooves where even a "sweet spot" no longer exists, can never be restored to pristine condition.  There simply isn't enough good audio information remaining with which to work.  Likewise, audio levels driven into severe clip or saturation pose similar results. We can run the audio thru a de-clipper that attempts to predict how the flattened top should look, but it's effective only in cases of minor clipping where it doesn't have to "guess" how much of the missing audio information might have looked.

Types Of Audio Transfers

Direct - Raw Transfer Only (Absolute minimal cost)

No restoration is employed - whatever was on the original source is accurately copied - including all the noise such as hisses, hum, clicks, pops, scratches, etc etc etc... The final CD is not broken down into tracks. It's one CD track of the entire recording. No Labeling - No Frills !

This is the least expensive type of transfer. It is the most effective means to get a precious recording preserved and archived at absolute minimal cost. It is also desirable by audiophiles who have their own restoration software but haven't the playback equipment to safely recover the audio stream from rare vintage formats, or for those who wish to experiment for themselves.

What it does give you is the best accurate copy of the master in a digital format for archiving or restoration at a later date.

Direct by Track

As above with no restoration applied, but the transfer is segmented into separate tracks before recording to CD for easy track selection.

Transfer & Global Restoration  (Best overall value)

Includes both transfer and restoration of the master.  First the separate audio tracks are copied to a hard drive then analyzed for the best overall restoration techniques to be employed for the entire final transfer. This level of restoration is quite effective for all tracks that came off the same record for example, as the type of noise encountered will most likely be consistent across the original disc.

For tracks spanning different sources, global restoration is usually not the best method, as the types of problems will all be quite different and thus a "one fix cures all" approach simply won't work well.

Transfer & Restoration by Track  (Highest Quality)

Every track is separately analyzed and the best restoration technique and filters are employed for each individual track. As you can imagine, this is more labor intensive and costs are based upon the number of separate tracks to be restored.

Saving your Audio Files - Philosophy of Audio Archiving

When archiving vintage recordings, the best strategy is to save two different copies of the audio file. The first copy or master, should be just the raw audio file that is an exact copy of the original disc with no restoration corrections applied. If equalization was applied to the master and the curve is known, use the reverse curve to cancel it out. If the restoration curve is not known as is usually the case, then it's best to just transfer it flat. All the crackles, pops, hisses are transferred as well, as it's imperative that as much audio information as possible from the master recording is captured and saved. Use the highest quality equipment you can afford as well as the optimum stylus selection. This file can then be used as a master reference zero starting point for future restorations. Keep in mind that future software technology will make great strides in restoration capabilities, and you or future generations will need that master reference copy to start the restoration process anew. Also, restoration is often a subjective matter - in the future, someone else may shudder in horror at your efforts in light of future technology advancements. Whatever cartridge you choose, make certain it is stereo, even although vintage recordings were only mono. Often times groove damage will be greater on one sidewall than on the other. You or future generations can then choose later what channel is best. Also, some transients may show up on one sidewall whereas they are not evident or greatly reduced on the other. Good restoration software will allow you to cut and paste between the tracks, basically selecting from the "cream of the crop" !

The other copy or copies, are the restored versions. The reason for doing it this way is that once restored with filters applied, it is very difficult (read: impossible) to undo the processing in the event you might desire to employ different restoration options in the future, or when you obtain better restoration software. Plus by saving a raw copy, you'll never have to play the record again and incur more wear and tear. Keep in mind the goal.... The digital master recording you just made, freezes degradation of the master media dead in it's tracks and is of utmost importance in true archival work. Future generations will bless you for your foresight in having made these efforts !
 
Even if you do not have restoration software yet, it's important that you at least get the files transferred and archived as a direct copy.  The more any disc is played or even handled, the greater the wear and tear - even on the best of equipment or exercising the gentlest touch.

Avoid saving the master archive files as MP3's or in any other compressed digital format for that matter, as an MP3 file is a highly compressed file. Although wonderfully compact, the compression/de-compression process results in losses.....  losses that can never be reclaimed.  Remember that something's got to give to reduce the file size, and that something is audio information. You want to capture it ALL.  MP3's are to audio as Jpeg is to images.....  It's best so save them as a WAV file which is uncompressed.  Each copy of a wav file format will be an exact digital copy !.......  It's the only way to go....

Vintage Recordings as a Hobby

Even though this is a business for us, it also remains a fun as well as rewarding experience, preserving vintage recordings. This site, though by no means a comprehensive resource, is filled with the basic information and understanding you'll need to get started off on the right track.

There are sections on turntable, cartridge as well as stylus selection as it pertains to vintage recordings as well as other tips .  Read More ...

MP3 Samples

The following are two MP3 clips.

The first is a typical un-restored vintage 78 full of crackles, pops, rumble and hisses.          Click Here to Listen....

The second is the restored version with the crackles, pops, rumble and hisses removed.    Click here to listen.....

 

here are numerous filters and algorithm's that can be employed to clean up most types of audio noise. We analyze the disc and then select only the appropriate filter, thus preserving as much fidelity of the source as possible.

 

 

There are numerous filters and algorithm's that can be employed to clean up most types of audio noise.

We analyze the disc and then select only the appropriate filter, thus preserving as much fidelity of the source as possible.

Noise in some cases depending upon it's signature, can be sometimes completely eliminated. In other cases, we can only achieve noise reduction.

 

Types of Audio Noise That Can often Be Greatly Reduced or Eliminated

Types of Noise

Scratches
Crackles
Pops
Buzzing
Rumble
Clicks and ticks
Hum
Constant pitch noise
Cylinder Noise
Static Noise
Tape Hiss
Vinyl Hiss
Motor brush Noise

 

Audio Compression and Expansion can bring out "bland" vocals or greatly reduce harsh dynamics.

DeClipping is a process whereby the flattened tops of the waveform can be predicted to reduce the effects of the audio being recorded too "hot" and overdriven.

Audio Enhancements

 

Enhancements

Add lost high frequencies by heterodyning up Mid-range to high freqs. (exciter)
Add warmth - A tube-amplifier sound
Cylinder Correct the pitch or the speed of a recording Noise
Remove excessive low or high frequencies
Compress or Expand dynamic range
Give recordings a crisper, digital sound
De-Clipper - improve fidelity in mild cases of overdriven audio

 

 

Limitations of Audio Restoration

Limitations

Damaged Discs -   Discs that are cracked into 2 separate pieces, or delaminated are simply that:  They are unplayable.
Poor Quality Masters -  The poorer the source material, the greater amount of processing that must be done and thus more "muddying" of the  material will result. Like everything else in life, it's not a perfect world. There's a tradeoff between the degree of noise noise reduction and fidelity.  It's truly amazing what can be done, but there are limitations. Even light to moderate filtering will vastly reduce the amount of pops, clicks hisses etc on poor material with very little negative effect on the overall fidelity. We can often turn lead into silver or at least polished oak,  but not into gold.
 
Off Center -  Records with off-center holes will play with the pitch varying slightly at each revolution. Correcting this defect is included (note: it will require a re-punch of the center hole)
Skips - if a record "skips" on your turntable, then it'll most likely "skip" on ours.  If the needle skips forward we will just simply continue the transfer.  If the stylus hangs up in place, we will gently nudge the needle into the next groove.  Cleaning up skips is often labor intensive and is billed at our professional level hourly rate. Please do not submit records that skip if these conditions are not accepted..
Severe Scratches -  Most vintage 78's result in up to 100,000 clicks, pops and scratches being eliminated.  Most short transient clicks & ticks are completely eliminated, without so much as a trace.  If the scratch is very deep, there will be a trace of a "pop" even in the restored version. This is due to the stylus literally "taking flight" by getting launched into the air.  While "airborne", there will be no audio until it "lands" again.  The resulting transient is simply too long of a duration to be cleanly filtered out. Put another way.... We can't filter out what isn't there. Manual editing, re-grooving or waveform matching are the only solutions and are billed at our professional level hourly rate due to the extensive labor involved. Even so, it may never be perfect if the damage is too severe.
Distortion -  There are all types of distortions.  Over modulation at mastering, poor disc pressing, distorted vintage microphones, worn records .... the list seems endless.  Our restoration software (or anyone else's for that matter) cannot distinguish between distorted and clean audio.... even if it could, it would have no way of re-constructing the data as there was no valid fidelity recorded to begin with.  It's somewhat akin to taking an out of focus photograph. There is no software or technique that allows it to be "re-focused"...  We can't cure something out of what wasn't there in the first place. If your record sounds distorted, then so will your restored copy.... It'll be much cleaner with the noise removed....  but just as distorted.
De-Clipping - Overdriven audio if not too severe, can often benefit from de-clipping. If clipping occurred only on the highs (ie the the top 5%) then de-clipping will be of benefit. Serious clipping where more than 30% of the waveform is flattened off, will not benefit much from being de-clipped. There's simply not enough information remaining to approximate the correct top portion of the waveform.
Other Limitations - Types of noise whose frequency distribution falls within the spectrum of the human voice or program material, is difficult or often impossible to remove. Current state of the art  software cannot differentiate between the two.

 

We can re-flatten many warped discs depending on the the type of construction.
(Since this is risky; We re-flatten only to the degree necessary to allow half speed mastering)

In cases where a disc is partially cracked (assuming it's not a glass substrate) we can often re-align the two sections.

 

Last Modified: Oct 19, 209

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