What are these old recordings supposed to sound like? Acoustic recordings were made without the benefit of modern electronic technology. They were mechanically recorded, and mechanically reproduced. Playing the old Victrola is fun, but ill advised if the record you are playing is 100 years old. Collectors also quickly find that a large collection gets pretty cumbersome, and would like to copy them into modern media for convenience and preservation.
A collector is also fortunate indeed if he is able to find a nice title over 80 years old and in excellent condition. Neglect and mishandling over the years makes us lucky to find anything in good condition. Steel needles needed to be changed with every play or the damage to the record groove was accelerated. This kind of damage is noticed by the whitening seen in the groove during louder passages. Bamboo needles were available, but the record was not as clear when played. The benefit of bamboo needles was the records suffered very little wear with playing.
Restoration of archival
materials is a difficult challenge. The risk is that in the process of
trying to improve the condition of the antique, it likely
that it may be permanently changed in a way which doesn´t represent its
original condition.
Using tape to repair
a old torn paper document is harmful because the adhesive will eventually soak into
it, and cause further damage. Repainting an old sign basically turns
it into a modern reproduction.
So, what is the warning we face with respect to these old recordings? Actually, we have two. The first, is that any electronic reproduction is a modification in itself. Some may respond, " yeah, well I use a microphone and make my recordings directly off an old Victrola". Well, the microphone, amplifiers, and recording media will all modify the way it will sound. Even the placement of the microphone and the acoustic space will have an effect. Most of us are using a modern turntable with a magnetic cartridge and a diamond needle close to the correct diameter for the groove. If we then run the input into a recording amplifier which is equalized for modern LPs, that modifies things further. We also record all of the low frequencies which are great for LPs but just don't exist on acoustic recordings. Audio tapes will add hiss and probably other problems as well.
The second problem comes when we try to restore the recording to it's original condition. There is a variety of software available over the Internet that have an impressive range of tools which lend themselves to restoration. The techniques of filtering, de-clicking, time modification, noise reduction, and others all are important tools but have the effect of further modifying the recording. An extreme example are those who try to create stereo effects, reverb, and bass effects to attempt to make these records more acceptable to modern ears.
There is a lot of debate on just what are the best methods of transfer and processing. The differences of opinion can get quite heated. Our formula is fairly simple:
Before digital recording was available, we really had no tools capable of making a recording ´archival´. Reel to reel audio tape was about all that was available to copy these records. Tape had serious problems. The first is that magnetic tape is susceptible to all sorts of things, such as print through, breakage, heat, etc. The next was that magnetic tape deteriorates with time. The magnetic oxide comes off the tape as the binder breaks down. The third is that copying from the tape will be of poorer quality than the original.
One big advantage of digital media is that each successive generation copy will be as good as the original. Lets assume that you have an old, yellowed, crumbling book, and that all you care about is the printed information on the page. If we took a typewriter and copied the book on new paper, exactly word for word, we would produce a perfect copy. Even if over time this copy got old and yellowed, someone in the future could still copy it again, preserving the information. This is what digital media does for us and old analog recordings.
One disadvantage of present day CD-R storage is the unpredictable stability of the materials used in making optical discs. A condition, called 'CD rot', has appeared on some older CD-Rs. A fractal-like erosion begins at the outer edge, and slowly works it's way into the disc.
If you are going to copy your priceless collection to CD, follow these rules:
Conclusion: Digital media has advantages which make audio archival work practical -- but keep backups and periodically inspect them!.
What happens when that tonearm meets the record groove? It´s actually an important question. A phonograph recording is a spiral groove which has a vibrating path to represent the sound. It is very important that the record needle fits this groove accurately, and doesn´t jump up and around in the groove, while reproducing the sound. Worn needles track poorly and will damage the record. Record groove diameters changed over the years, and it is important for you to have a proper needle, for the type of records you will record. Record players made after World War 2, are equipped with needles for playing records of that period. Earlier disks have larger groove diameters, and need wider needles. They still play on newer machines, but with reduced quality.
We use an unusual reproducing method at Meloware. Antique records were designed to be played with clean, new steel needles. A steel needle quickly shapes itself to the groove wall, creating a custom fit. We use a vintage Western Electric 4A reproducer (developed by Bell Labs) and a steel needle, which is replaced for each recording.
Aside from a good fit, the needle also must have enough weight applied to stay reliably in the groove. LP vinyl records are happy with weights as low as a gram or less. Antique 78 rpm records were played with several ounces of weight! If your needle is proper for the records you are recording, it is fairly safe to add 5 grams of weight to your tonearm (a nickel coin). You might like to compare the results, with and without the weight. There can be a big difference.
The cartdrige is the instrument in the tone arm, which translates the vibrations in the record groove to an electrical audio signal. Its function is crucial to the final quality you will get in your transfer.
There are two types of phonograph cartridges, magnetic and crystal. The magnetic cartridge produces the most accurate quality of these two types.
We recommend NOT using a crystal cartridge, which came with many of the cheaper units during the 50's and 60's. These devices use a pizo-electric effect to produce a signal, and are unable to reproduce sound at an even level, across the range of tones in the record. Your recordings will probably sound much scratchier than they actually are. Crystal cartridges also have a limited life expectancy. Don´t be suprised if the old, cheap record player doesn´t even work.
Make sure that your turn table operates quietly and is not going to introduce all kinds of rumble into your recordings. See that the turn table is on a solid platform and not some card table which will carry up all the vibration produced when people walk around the floor.
Make sure everything is grounded! There is no need to record 60 cycle hum. It can be filtered out, but if the problem is bad it can produce products in the higher frequencies which you won't get rid of. Proper grounding can also possibly eliminate radio interference from nearby stations.
Magnetic cartridges designed for playing 45´s and LP´s produce a
tiny electrical signal, which needs amplification before it goes to your sound
card. Record Players of the 1960´s and 70´s have this
feature built in, but poses a problem for people wishing to make copies of
recordings produced before the 1950´s. Vinyl LP records were made with
a special filtering method, know as RIAA equalization. This was to allow low
bass tones to be in the record, without taking up too much space from the record surface.
You do not want this built-in filtering when recording antique records.
The only way to avoid this is to know how to bypass this equalization in your pre-amp,
or to use a separate microphone pre-amplifier, before the audio is connected to your sound card.
These old records are monoaural, not stereo. There is only one channel of sound. If you are using a stereo cartridge(and most likely are), you should still connect both left and right channels to your computer. A stereo cartdrige isn´t really the correct animal to use for monoaural recordings. You should be recording in monoaural mode, with your computer, but will first need to experiment with the left and right channels to see what kind of combination produces the best sound. You should be able to try left, right, or an even mix of both.
Be sure to test your system out well, before attempting to do a lot of work, which you may regret later. It is a good idea to first connect everything together and make an empty recording, with the record input volume turned way up. This will help you locate any sources of hum and unnecessary noise. Remember to keep all but the needed phono input switched off on your sound card. Other input sources, which are still connected to your system, may introduce added noise to your recordings.
Verify that your system is hum free and noise is very low. See that each channel from the cartridge produces the same volume in your computer, and that these levels are capable of recording at full volume with your audio software. You should then reduce the volume in your pre-amplifier to the minimum level needed to do the job. Remember, that each amplifier you use in the chain to your recording is going to have it’s own noise, distortion, and hum susceptibility.
If all of this checks out well, you should be ready to do some good stuff. Get to know your audio recording/editing software, before trying to do too much. Reserve a directory in your computer´s hard drive, for keeping your new recordings, and back them up to CD as soon as possible. You will want to save all your PCM/WAV files in their direct and original form, and make backup copies. SAVE YOUR ORIGINAL WORK AS UNCOMPRESSED FILES, NOT MP3s! Mp3s are fine for enjoying, but you throw away audio information when making an mp3. It is a lossy form of compression.
Remember that any archival work should
not do anything to permanently change or damage the originality of the
item. This point is respected by archiving FIRST the original digital recordings
as they are produced by your best available playing system. After this,
you can have all kinds of fun experimenting and working with restoration.
You will always will have your original worked saved if you decide later
that you were doing something wrong and want to start over.
|
|
|
|