Corey Bailey

           Audio Engineering

USEFUL INFORMATION RECORDS:  DO IT YOURSELF?

I would like to start by reminding you that if you have any old family recordings on disc, please have them transferred professionally before attempting to play them. They are very fragile and easily damaged. That said, collecting records can be fun and rewarding. I always enjoy perusing the used records at a thrift store, hoping to find something in good playable condition that hasn’t made it to Compact Disk. If you haven’t cataloged your collection yet, now is the time because it would be good to establish which material has already been produced on CD. Digitizing the records you have will not necessarily produce sound files which sound better than the commercially-produced CD's, so the decision to digitize them is yours. It is, after all, good practice. This leaves you with the material that can’t be found on CD; there is still a surprising amount left to be transferred to the digital realm. Digitizing copyrighted material for your own use is legal (in the U.S.A.) so, all you need is the equipment, the knowledge of how to use it, and the time to do it. You will need a turntable, connected to a phono preamp, connected to an Analog to Digital (A/D) converter, connected to a dedicated computer with dedicated software for recording and creating (burning) CD’s. Entry level for the equipment and software to do the job will run about $2500.00. If this sounds expensive, consider that a restoration quality turntable, by itself, with an adequate selection of cartridges and styli can cost $3000.00 or more. Another possibility is to buy a turntable with a USB connection that connects directly to your computer for digitizing records. The downside of these turntables is that they tend to be one-size-fits-all players and won’t give you the best possible transfer for every format. We’ve had two of these turntables (different brands) in our family that belonged to my children, who also enjoy searching thrift stores for old records. We have discovered that the digitized sound quality produced by these types of turntables is average at best. If it’s really important, they bring it to Dad. If, however, you are mainly interested in creating compressed MP3 files or making up some travel music for driving in the car, a USB capable turntable may just do the job. Some of these models have analog outputs as well as digital, and my son discovered that using the analog output with a component setup as described above yields better results. Records take their own special preparation in order to get the best performance. This will involve careful examination and cleaning (sometimes extensively) before you select the proper stylus in order to get the best possible transfer. There are several methods and cleaning machines available. When it comes to selecting the best stylus, use your ears as the final judge. Because of groove wear, I have sometimes made three transfers of the same side for 78RPM records: Above the wear pattern, At the wear pattern (in the groove, as they say) and below the wear pattern, closer to the bottom of the groove. The three transfers gives me (or the customer) all of the possible choices. Sometimes, after playing an entire side, you will want to try it again with a different stylus or cartridge to possibly improve things. This is why a through cleaning is so important. If you are merely a listener and are only interested in playing records for your own enjoyment, the same will apply. There is some good reading at the Library of Congress website: http://www.loc.gov/preservation/care/record.html I would also recommend that you consult Wikipedia for a reasonably in- depth description of how records work. Search the terms Gramophone Record, Turntable, Phonograph and Magnetic Cartridge, and you’ll become reasonably well educated regarding the whole process. There is some very good advice out there on the internet, but be careful. Often, what seems like good advice is really someone’s opinion. Look for good science and well established procedures. Check out my links page for additional resources. I have assembled some simple glossaries that are specific to records and analog tape that may help as well. LP’s: As you may have already learned, the microgroove, long-playing, vinyl record was first introduced in 1948. However, the 33-1/3 RPM long-playing record format was first patented in 1931. The speed format had been used since the late 1920’s when sound for motion pictures was introduced by the Warner Brothers. This consisted of discs mechanically synchronized to a film projector. This process (and the discs) was called Vitaphone. The 33-1/3 speed format wasn’t well received by the record- buying public when it was first introduced in the early 1930’s as people were already set up for the 78 RPM record. However, it became popular as a format for 16” diameter discs used for transcribing radio broadcasts. These early versions of the 33-1/3 speed format used the same groove width as 78 RPM discs. Both the early movie sound (Vitaphone) and radio transcription disks were cut, one at a time, into nitrocellouse lacquer coated blank discs and were designed for only a few plays. Some of these disc types had a center of aluminum and some were glass. The discs that were lacquer coated glass came into being during WWII as aluminum was in short supply. If you own or come across any of these, please understand that they are very, very delicate and can be easily damaged by incorrect equipment or handling. On the subject of handling: DO NOT touch the surface of any lacquer coated instantaneous disk with your bare hands. The moisture and oils from your skin can cause a chemical reaction  that, over time, leaves a permanent mark and can affect the playability of the disk. When handling any lacquer coated disc, use cotton or rubber gloves to avoid direct contact with the surface of the disc. That said, some radio transcription disks were manufactured as vinyl discs for distribution to many radio stations. Microgroove LP’s were monaural until 1957 when the Stereo LP was introduced. The question is often asked by those who enjoy collecting old LP’s if it is OK to play an old mono vinyl record with a stereo stylus. The short answer is yes. A properly adjusted turntable with a stereo cartridge and stylus will not physically damage a mono LP, and, likewise, a properly adjusted mono stylus will not damage a stereo LP. There are however, some trade-offs: Playing a stereo record with a mono cartridge and stylus: The information on a stereo LP is derived from the opposite sides of the grove wall. The grooves are cut at 90 degrees (right angle), with the inner side of the groove containing the Left Channel information and the outer groove wall containing the Right Channel information. A monaural cartridge and stylus is designed to only move laterally (side-to-side). So, the stereo information is summed to mono. The balance of the original stereo mix can be altered by possible phase cancellation of common signals on both sides of the groove wall. Another, more common, effect of playing a stereo disc with a mono stylus is that the (in phase) common information on both sides of the groove walls will sum and increase dramatically in volume, causing an alteration of the intended blend of instruments and vocals. This is most noticeable with vocals, drums and any instruments originally placed in the center of a stereo mix. Another side effect that can often be noticed is a reduction of the echo that was inherent in the original stereo mix, because echo (reverberation) is random by nature and some of it will phase cancel causing a comb filter effect. It all comes down to just how mono- compatible the original mix was. During my tenure as a Recording Engineer and Mixer, nearly all of the stereo mixes destined for albums were mixed strictly for stereo listening, and mono compatibility was often disregarded even though I always suggested that stereo mixes be listened to in mono before final approval. Any singles derived from albums were remixed for mono compatibility to be played on AM Radio and were released on the 45 RPM format discs.  Many 45 RPM discs are stereo which leaves it up to the AM radio station to perform the mono compilation. Playing a mono record with a stereo cartridge and stylus: Monaural Lp’s were recorded laterally (or horizontally). If you think of an imaginary line in the center of the groove as you look down on it, each groove wall has an equal part of the signal or waveform. So now, we’re going to play this groove with a stylus designed to play each side of he groove separately. What happens is that when the Left + Right information is played as mono (as it should be), out of both channels of your stereo system, it will sound OK. I say OK because any common information can be phase canceled when played as mono so the record may not sound quite as good as it would when played with a mono cartridge. The random surface noise (clicks, pops, etc.) will play in stereo while the mono mix is in the center of the sound field. If your stereo system has a mono switch, use it when playing mono records on your stereo turntable and it will phase cancel some of the surface noise. If you rotate your balance control from side to side while playing a mono record on your stereo turntable you should notice no difference in fidelity. It all depends on small differences in record wear, stylus wear, manufacturing tolerances, etc. The practice of retrieving the sound from Edison cylinders and obscure 78 RPM records using a stereo cartridge and stylus, is well known among archivists. The idea is to be able to use the best results from either channel. This process is often used for those recordings which require a substantial amount of restoration. Here is a link to an excellent representation of how the various styli track a record groove: http://www.vinylrecorder.com/stereo.html I should point out that some early manufacture turntables and styli can damage a disc by applying too much force or, at least, cause additional wear to an otherwise playable record. These are usually the inexpensive types that often have a “flip- over” cartridge to accommodate both LP’s and 78 RPM records. More often than not, these “one size fits all” players will be improperly adjusted for both formats. 78 RPM Records: (Shellacs) Commercially produced records of the 78 RPM era were often called “Shellacs” because the discs were comprised of a mixture of ingredients that were bonded together by shellac. The mixture of ingredients was generally a closely guarded secret held by the various record companies. Be very, very careful when handling these discs. They are very brittle. When cleaning these old discs, know the ingredients of any wet solution you plan to use. Alcohol based solutions, for example, will damage this type of disc. Very old 78 RPM records, manufactured around the beginning of the Twentieth Century, will, as often as not, have to be speed corrected to obtain the correct pitch of the music recording. This is because the developed standards were loosely adhered to until about 1925. After that, the vast majority of 78 RPM records produced in the US were actually recorded at 78.26 RPM, while the majority of discs produced in Europe were recorded at 77.98 RPM. The reason is that the electric motors (from the mid-1920’s onward) used to spin the platter for disk cutting lathes and consumer record players were  referenced to the power line frequency, which is 60Hz in the US and 50Hz in Europe. The standards for the manufacture of 78 RPM records regarding the Record/Playback equalization were quite often different from one record company to another until things were standardized in the late 1930’s. This is the area that will involve the most research in order to properly play most 78 RPM records. Instantaneous discs: Home Recordings Once in a great while you may come across homemade disc recordings. These records are often referred to as “instantaneous discs”. There were several brands of record recording machines produced for the consumer market during the 1930's, 40's and the early 1950's. These one-off recordings were typically laminated with vinyl over a composite (cardboard like) center layer, and some are (typically black) lacquer applied to an aluminum disc. Many have not survived in playable condition. Those that have are extremely delicate. During this same era there were some disc recording machines in the local variety and department stores, and for 25 cents or so you could make a recording. During World War II, one could find those record making machines in the local USO and they were popular for sending voice letters overseas. The department store vending machines survived into the 1950's in some areas of the USA and if you have any of these recordings made by your relatives, I strongly suggest that you contact a professional to have transfers made before attempting to play any of these types of disc. Know that the same handling precautions apply as mentioned above for lacquer coated discs. I have digitized a number of these homemade discs. I’m perfecting a process to flatten them and reduce the severity of the ridge-like cracks that tend to form over time on the vinyl over composite variety. So far, I’ve been able to reduce the physical problems by an average of 75%, which has made some discs playable that would have otherwise been lost to time. I plan to eventually publish my findings and describe the process which should be relatively easy to replicate. If you have records made from the turn of the last century up to the early 1950’s, you will need a turntable that can accommodate the various sizes of discs and be capable of a variable speed of at least plus or minus 20%. You will need a phono preamp with separate equalization (tone) controls in order to achieve the proper playback equalization. Additionally, I would recommend a selection of 78 RPM styli in order get the best fit to the various groove types that were cut, and be able to allow for groove wear. In conclusion, in order to get the best possible fidelity from any record, it should be played with the cartridge and stylus for which it was designed. Getting the best out of your record collection does have a learning curve and you can get as involved as you like. That's the fun of it! Return to TOP of page © Corey Bailey Audio Engineering

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