458 American Archivist / Vol. 58 / Fall 1995 Downloaded from http://meridian.allenpress.com/american-archivist/article-pdf/58/4/458/2749659/aarc_58_4_h0574104424k4376.pdf by guest on 28 September 2021

Lasers and the Fate of Phonographic Recordings by MATTHEW SPRINKLE

Abstract: Conventional methods cannot always be used to play back sound recordings from old and/or damaged phonographic cylinders and discs. New compact disc technology uses lasers for quality and precision playback of sound recordings. To what extent can lasers be effectively used on phonographic media? Laboratory work and attempts at mass marketing provide interesting insights for sound archivists.

About the author: Matthew D. Sprinkle earned a B.A. in Music (1986), and an M.A. in Music Theory and Composition (1992), from the University of Wyoming. He has worked as a guitarist, keyboardist, composer, soloist, singer, and recording engineer in styles as diverse as classical, rock, atonal, and the blues. He won the 1986 Wyoming Music Teachers Association composition contest, college division, with his "Vistas 1 & 2" for classical guitar. The Owen Wister Review (literary/ arts magazine) has twice published his poetry. A member ofSAA, AMI A, ARSC, and SRMA; he is the Audio-visual Archivist of the American Heritage Center, University of Wyoming. Lasers and the Fate of Phonographic Recordings 459

LASER TECHNOLOGY HAS BEEN developed Discs were pressed in a variety of di- to the point where it is useful in many dif- mensions and materials through the years. ferent fields including; medicine, chemis- The early 78 rpm discs were mainly shellac try, communication, photography, and and were thicker than the subsequent vinyl

nuclear fusion. Its use in modern sound re- records with sizes ranging from three to Downloaded from http://meridian.allenpress.com/american-archivist/article-pdf/58/4/458/2749659/aarc_58_4_h0574104424k4376.pdf by guest on 28 September 2021 production begs the question from sound sixteen inches in diameter. Pathe even pro- archivists, "Can lasers help us to repro- duced a 20" disc that was designed to spin duce the sound from old recordings?" at 120 to 130 rpm.5 The speed for cylinders The oldest items found in most sound also varied from 100 to 200 rpm, although archives are phonographic cylinders and they were usually either 120 or 160 rpm. phonographic discs. Some of these items Speeds for discs varied until 78 rpm be- were made of durable materials (although came the first standard, with 33 1/3 and 45 the grooves themselves are fragile) and are rpm quickly following suit. Other special still in good condition nearly one hundred considerations facing sound archivists in- years later. Many films and audiotapes clude nonstandard groove dimensions and which are much younger are more fragile, layouts, vertical and lateral types of cuts, and have been more prone to deterioration. variable spindle hole dimensions, and The problem concerning the phonograph proper equalization.6 (Equalization is the items tends to be how to acquire the right manipulation of parts of the frequency machinery for playback. Old cylinder ma- spectrum during recording and playback, chines are often rare and expensive, and which provides linear reproduction of the must be customized in order to transfer re- recorded signal.) Matching the original re- cordings directly to a modern medium.1 cording's equalization can be a problem, as Most of the cylinders and discs were de- there were no standards before the 1950s. signed to work with specific styli. Origi- With the advent of electrical recording it nally they were made of steel. It was found became possible to manipulate (or equal- that these were too hard on the discs, which ize) the recorded signal. Low frequencies was also the case with the subsequent could be amplified if they were lacking in chrome or gold plated steel needles. There the signal. Ultimately, many recording were even styli made from fiber and from companies equalized recordings as to what treated and untreated cactus needles.2 By they thought the artist or instrument should the time microgroove records appeared in sound like, as opposed to how they really the late 1940s, the industry settled on sap- sounded.7 Two main types of equalization phire and diamond styli.3 The shape of the techniques were diameter (to compensate stylus also changed through the years from for the changes in groove velocity from a spherical shape for the 78 rpm discs to outside to inside the disc) and frequency- an elliptical shape for long-playing rec- response (to compensate for the nonlinear ords.4 effect of the disc cutting equipment). A third type of equalization was applied by manufacturers to achieve a "house" 'George Blacker and Robert Long, "How to Play Old Records on New Equipment," High Fidelity 23 sound. Equalization practices became uni- (April 1973): 48. form when an industry-wide standard was 2Oliver Read and Walter Welch, From Tin Foil to Stereo (Indianapolis: H.W. Sams, 1976), 549. 3Henry Currall, ed., Phonograph Record Libraries (Hamden, Conn.: Archon Books, 1970), 128-29. 5Blacker and Long, "How to Play Old Records on 4Jerry McWilliams, The Preservation and Resto- New Equipment," 52. ration of Sound Recordings (Nashville, Tenn.: Amer- 'Blacker and Long, "How to Play Old Records on ican Association for State and Local History, 1979), New Equipment," 49. 68. 'Read and Welch, From Tin Foil to Stereo, 239. 460 American Archivist / Fall 1995

finally agreed upon. A curve for frequency- consistent. Rumble is the presence of low- response equalization was adopted by the frequency noise along with the recording." Recording Industry Association of Amer- Chances are that an acoustic phonograph ica (RIAA) in 1953.8 may also damage the recordings. Stylus

The practice of electronically enhancing forces on these models tended to be in frac- Downloaded from http://meridian.allenpress.com/american-archivist/article-pdf/58/4/458/2749659/aarc_58_4_h0574104424k4376.pdf by guest on 28 September 2021 recordings became standard procedure tions of a pound rather than grams, as with through the years to the point where every modern turntables.12 Often the recordings kind of recording we hear has been manip- are too fragile to be played back as they ulated to some degree. It may be said that were originally intended. Even under op- today's recording engineers are practicing timum playback conditions, minute dam- sound production rather than accurate age to the grooves of recordings is sound reproduction. This, then, leads to the inevitable. A stylus force of just one gram dilemma of deciding how to be faithful to from a microgroove cartridge can produce original recordings during transfer to mod- a pressure on the groove walls of between ern media. 6,000 and 16,000 pounds per square inch. Should we desire to "clean up" the re- The point of stylus-disc contact may also cordings? Electronic systems using algo- develop a temperature of up to 2,000 de- rithms have been designed which can grees Fahrenheit (which is why discs remove scratches, impulsive noise, and should never be played more than once 13 white noise.9 Another question arises as to every twenty-four hours). whether we are more interested in what The sound archivists find themselves be- was recorded (the information) or how re- tween the proverbial rock and a hard place. cordings were made and heard in their day On the one hand, we want faithful repro- (the hardware). duction of the recordings, but on the other Most technicians used to think that hand we want to preserve these recordings proper playback of phonographic media from any more damage than they have al- should be done on original equipment only. ready sustained. Is this a basic contradic- The idea is that only original equipment tion, or is it possible to have the best of will faithfully reproduce the recording the both worlds? way it should be heard. It is true that the The idea of tracking grooved discs with acoustic resonances of the old playback a light beam instead of a stylus is not new machines may correct some of the prob- — inventors have been experimenting with lems in the original recording equipment, optical turntables since Friebus in 1929. In but sometimes the acoustic horns create 1941, Philco was advertising a photo-elec- unintended distortions.10 Usually, the old tric radio-phonograph, and in the 1960s, machines are noisy and suffer from the Britain's Decca commissioned PA Tech- three classic phonograph problems — nology to create a system of cutting master wow, flutter, and rumble. Wow and flutter discs with a light beam instead of a dia- occur when the revolution speed is not mond chisel. These projects eventually failed.14

8McWilliams, The Preservation and Restoration of 1 'MeWilliams, The Preservation and Restoration of Sound Recordings, 10. Sound Recordings, 10. 9S.V. Vaseghi and R. Frayling-Cork, "Restoration 12Currall, Phonograph Record Libraries, 128. of Old Gramophone Recordings," Journal of the Au- 13McWilliams, The Preservation and Restoration of dio Engineering Society 40 (October 1992): 791. Sound Recordings, 56. '"Blacker and Long, "How to Play Old Records on '"Barry Fox, "Laser Turntable for Vinyl Discs," New Equipment," 49. Studio Sound 32 (June 1990): 109. Lasers and the Fate of Phonographic Recordings 461

The idea sounds relatively simple. Two methods of reproduction were de- Merely beam the light from a crossed pair vised for the cylinders. One method used of lasers onto the groove walls and use a an original Edison phonograph with a cus- light sensitive strip to read the angular de- tom-made light pressure stylus. This stylus

flections of light caused by the groove was able to reproduce the recorded sounds Downloaded from http://meridian.allenpress.com/american-archivist/article-pdf/58/4/458/2749659/aarc_58_4_h0574104424k4376.pdf by guest on 28 September 2021 modulations. These signals are then trans- without damaging the grooves, as a normal lated into audio signals and recorded onto stylus can. Forty-one cylinders were trans- magnetic tape.15 "Easier said than done" ferred in this manner. The twenty-four re- became the unfortunate response from the maining cylinders, which were cracked or industry. Use of lasers did become the broken in pieces, were repaired, but were norm, however, with the new compact disc still too fragile for stylus playback. The la- technology. The compact discs are digitally ser-beam reflection method was developed encoded and read by laser. Why, then, was for noncontacting and nondestructive play- the industry having problems using this back of these fragile cylinders.17 technology on old recordings? The laser-beam reflection method con- As it turns out, the problem was not sists of three parts; illumination, driving, whether it could be done or not, but under and detection. The illumination consists of what conditions it could be done consis- a laser emitting a Gaussian beam whose tently. There are two distinct worlds of op- wavelength is focused by a lens. Adjust- eration — the laboratory and the ment of this lens allows the spot diameter commercial mass-market. As usual, a look of the illuminating beam to be focused to at one brings us around to look at the other. the size of the grooves. Bronislaw Pilsudski was a Polish anthro- The driving mechanism consists of a pologist who traveled to Japan to study the shaft which holds a wax cylinder, rotating culture of the Ainu people in Sakhalin and it at 150 rpm, by means of an adjustable Hokkaido. From 1902 to 1905, he recorded ac motor. The shaft and cylinder are then the talk and songs of these people onto wax placed on a movable stage. This stage has cylinders. In 1977, these cylinders were re- a stepping motor (synchronized with the ac discovered in Poland, and folklorists and motor), which moves it a distance of one anthropologists from both countries be- groove for every rotation of the wax cyl- came very interested. The folklore of the inder. This allows it to move parallel with Ainu had since been lost and there was the cylinder, the way a stylus would. hope that the cylinders would provide val- Detection consists of a detecting plane uable opportunities for study. The Inter- set perpendicular to the optical axis of the national Committee for Restoring and illuminating beam. The plane is a 1-D po- Assessing the life and works of B. Pilsud- sition-sensitive device. The photocurrent ski (ICRAP) was organized with coopera- signals which it detects are electronically tion from both Poland and Japan. converted into sound signals. The sound is Pilsudski's sixty-five cylinders were sent to then recorded by a tape recorder after being the Research Institute of Applied Electric- amplified with an audio amplifier.18 ity, Hokkaido University, Japan, in 1983.1S Certain problems were encountered when it was found that the quality of tim- ber and noise varies with the size of the

"Fox, "Laser Turntable for Vinyl Discs," 109. l6Toshiaki Iwai, et al, "Reproduction of Sound "Iwai et al., "Reproduction of Sound From Old From Old Wax Phonograph Cylinders Using the La- Wax Phonograph Cylinders," 597-98. ser-Beam Reflection Method," Applied Optics 25 "Iwai et al., "Reproduction of Sound From Old (March 1986): 597. Wax Phonograph Cylinders," 599-600. 462 American Archivist / Fall 1995

illuminating beam width. With a decrease fraction method was devised for the discs in beam width, the fidelity and loudness of which have a lateral (horizontal) groove noise are enhanced; with an increase in the cut.20 beam width, the high-frequency compo- Although the basics of the two systems

nents of the reproduced sound are greatly remained the same, some changes were Downloaded from http://meridian.allenpress.com/american-archivist/article-pdf/58/4/458/2749659/aarc_58_4_h0574104424k4376.pdf by guest on 28 September 2021 decreased, so that fidelity is greatly degen- necessary. Due to the grooves, the reflected erated. Noise is inherent in the method, due laser light suffered from a phase shift pro- to reflected ray spots at the detecting plane portional to the depth of the detecting called speckle patterns (or speckle noise). plane.21 More position-sensitive devices The high-frequency aspects of this noise were needed to track this diffraction pattern can be suppressed using a larger diameter than were needed to track the beam in the beam and the low-frequency noise can be reflection method. suppressed using a high-pass filter. The diffraction method suffered from Echo is another problem created when many of the same problems as the laser- the illuminating beam width is larger than beam reflection method, including speckle the groove width and therefore illuminates noise and tracking problems. While the neighboring grooves on either side. This sounds were successfully reproduced, even creates an echo effect along with the main from rusty records, it is arguable as to signal. whether the laser method of playback de- A tracking error can also occur with this livers better quality playback than a stylus method because it does not directly trace on records in good condition.22 the grooves of the cylinder, as does a sty- The Japanese scientists behind these ex- lus. To avoid the tracking error, a 2-D po- periments proved that the methods work, sition-sensitive device is used to detect the although there are interesting problems that error and feed it to the lens for compen- have to be solved. They found the pro- sation.19 cesses difficult even under their own lab- It was concluded that the laser-beam re- oratory conditions. What, then, are the flection method had inherent problems that chances that a mass-marketable laser sys- were fairly well-resolved. The fact that it tem can be produced? is a noncontacting method made it an in- In 1985, a California company called valuable tool for the reproduction of the Finial promised to mass-market a laser fragile Pilsudski cylinders. turntable for the reproduction of phono- A few years after the laser-beam reflec- graph discs. It was claimed that the ma- tion method was devised for the cylinders, chines would be available for about $4,000 many old phonograph discs were found in each, but every year the launch was post- Japan. These discs contain speech and song poned.23 In 1989, the company gave up, of native Formosan tribes. Some of these claiming that the technology could not be old discs were made of ebonite, some of made to work reliably at a reasonable price aluminum, and most were covered with mold — many of the aluminum discs were rusty. Ordinary reproduction techniques 20Jun Uozumi and Toshimitsu Asakura, "Repro- could not be used. Whereas the laser-beam duction of Sound from Old Disks by the Laser Dif- reflection method was devised for cylinders fraction Method," Applied Optics 27 (July 1988): which had a vertical groove cut, a laser dif- 2671. 21Uozumi and Asakura, "Reproduction of Sound from Old Disks," 2672. 22Uozumi and Asakura, "Reproduction of Sound from Old Disks," 2676. "Iwai et al., "Reproduction of Sound From Old 23Barry Fox, "Unkept Promises of a Laser Turn- Wax Phonograph Cylinders," 601-3. table," Studio Sound 31 (May 1989): 58. Lasers and the Fate of Phonographic Recordings 463

(Finial offered the few working models structive method of playback but don't they had for $26,000 each24). A Japanese want to play original items over and over. company bought the invention and began What is needed is one good transfer to working on their own prototypes. magnetic tape or compact disc, then the re-

Once again we find that the machinery cordings can be duplicated onto cassette Downloaded from http://meridian.allenpress.com/american-archivist/article-pdf/58/4/458/2749659/aarc_58_4_h0574104424k4376.pdf by guest on 28 September 2021 works but is susceptible to certain prob- tapes for use as disposable copies. The lems. Discs have to be exceptionally clean original item can then be stored properly, because the laser will read both groove without the constant abuse of being han- sound and specks of dust. Whereas a stylus dled, cleaned, and loaded and unloaded shovels dirt out of the grooves as it tracks from the machine. There is an indication a record, the light beam just reads it as part that repeated cleanings can be more dam- of the signal. These specks of dust translate aging to a phonograph record than playing into pops, clicks, and other unwanted noise it with a stylus.27 There is also a non-real along with the recording.25 time playback method using lasers to scan The National Library of Canada ac- discs. This technique, however, can take as quired one of the laser turntables made by long as two weeks to reconstruct the sound 28 the ELP company of Japan, which bought from just one disc. The laser methods be- out Finial. E-mail from Gilles St-Laurent gin to give us what we need, but fall short of the NLC described his experiences with of making themselves worth the money. this laser turntable. He confirmed that the Many archives could not afford them even laser turntable is limited in certain ways: It if they were completely reliable. will not play records that have a vertical It seems that, for the near future, sound groove cut, it will not play records that are archivists have no choice but to continue not black, and it has problems with acetate using traditional methods of sound repro- discs. In addition, turntable platters must duction (rebuilt cylinder machines and spe- be used to make up for the different thick- cialized turntables with proper styli) until nesses of old 78s and modern LPs, and the the laser technology can become more re- discs must be very clean for proper repro- liable and less expensive. It is possible that duction.26 Except for these basic problems, the day will come when laser technology St-Laurent is happy with how the turntable will be used to play back all kinds of pho- performs with modern LPs. His patrons can nographic items, no matter what features play discs again and again without stylus they have. Perhaps computers can be used damage to the grooves, and this is where to help overcome the typical problems, and he thinks the technology really shines. help this technology to become the saviour Although sound archivists applaud the for the old and fragile recordings in our machine and its link to the future in the archives. Until that day arrives, we must chain of technology, they are also curiously protect our sound collections as carefully left standing back at square one. Sound ar- as possible, in hopes that someday the chivists need a noncontacting and nonde- guiding light of the laser can reveal the an- cient sounds therein.

24Fox, "Laser Turntable for Vinyl Discs," 109. 25Fox, "Laser Turntable for Vinyl Discs," 109. 26 "Fox, "Laser Turntable for Vinyl Discs," 109. E-mail from Gilles St-Laurent of the National Li- 28E-mail from Norm Sohl dated February 25, 1994. brary of Canada dated March 2, 1994.