[TNT-Audio Vintage column] The Edison Disc Reproducers: A Comparative Survey I

Product names: Edison Standard, Long Play, Dance, and Edisonic Diamond Disc reproducers
Manufacturer: Thomas A. Edison, Inc. - USA (defunct)
Author: David Hoehl - TNT USA
Published: November, 2024

The critical component of phonographs designed for acoustic playback - whether because they predated electronic amplification, were backward-looking products of the transition period, or were for portable or other use when electricity was unavailable - was the “reproducer,” also known as “sound box,” roughly analogous to the cartridge of a modern turntable. A reproducer incorporated a stylus or needle that rode in and was vibrated by the record groove; a diaphragm, supported and sealed by rubber gasket tubing, that would translate those vibrations into larger vibrations in the air for transmission through a horn to come up to room volume; and some sort of linkage, generally what amounted to a lever, to connect the two. In the world of disk playback, such devices almost universally embodied a similar design, with the diaphragm in a vertical housing, face open to the air. For lateral cut records, modulated side-to-side, like those of Victor and Columbia, the housing would be set at right angles to the tonearm, pointing to the side as the record played; the Victor reproducer in the top photo to the right is an example. For vertical cut records, modulated up and down, like Pathe and an array of other, smaller makers that came and went, the housing would point forward, with the stylus or needle set at something like a 45 degree angle to the flat record surface, like the one in the bottom photo to the right. Sometimes it might be designed for universal use; Pathe's cabinet type machines sometimes put the reproducer itself at an 45 degree angle to the tonearm, and other makers provided either alternate reproducers that could be swapped onto the tonearm or some sort of rotary arrangement for turning reproducer forward or sideways as need be.^[1]

The Edison design. As illustrated in the photograph to the left, Edison's disc reproducers, designed to play the company's similarly unique vertical cut records, placed the diaphragm horizontally, and they completely surrounded it with metal rather than leaving its face open to the air. Moreover, they incorporated a tube that made them an extension of a hermetically sealed horn assembly, rather than connecting to a swiveling tonearm, and they relied on a floating weight to establish tracking force rather than resting the entire assembly on the point of the stylus or needle. The diamond stylus, which was electroplated to a stylus bar and compliant only vertically, rode freely in the record groove, held in place by the floating weight, with a mechanical feed system carrying it across the record. The stylus bar acted as a lever, with the fulcrum set between the stylus at one end and a link to the diaphragm at the other; in conjunction with the floating weight, which not only imposed tracking force but also put the diaphragm under tension, this arrangement acted as a mechanical amplifier, and at their outset Edison discs were noted for developing unusually powerful volume by then-prevailing standards. Indeed, public complaints that the machines were too loud led Edison to add a “tone modifier,” a large ball of soft material that, by sliding a tab by the turntable, could be rammed into the throat of the horn, rather like a brass instrument mute. The Edison disc reproducer design represented an adaptation of Edison's cylinder reproducers, also a world unto themselves, for disc playback. No one else in the industry did anything similar.

Edison's disc reproducers differed from those of other makers in another respect: the material of their diaphragms. Edison built up diaphragms from multiple layers of compressed rice paper impregnated with shellac, then stiffened with cork on one side and an ivory cap on the other. Silk thread connected the diaphragm to the stylus bar as outlined above. By contrast, most disc makers' diaphragms were mica, and the stylus linkage invariably was some form of metal bar.

Edison reproducer models. Edison offered four models of disc reproducer, with release of three clustered toward the end of the company's existence. The first was the standard disc reproducer issued with the first Edison disc phonographs in around 1913 (development and release of the disc phonographs was a complicated, lengthy, messy process). For about 15 years, it was the company's sole offering, although it did go through a few minor revisions over its lifetime. The most obvious to the naked eye was the mounting of the stylus bar. At first the mounting lugs were part of a metal plate screwed to the floating weight; later, they were molded directly into the weight itself. The upper photo to the right shows the earlier mounting technique, the lower photo the later one. (Photos not to scale.) Other changes not so visually evident included things like making the floating weight slightly heavier and modifying the profile of a depression in its upper surface, which was included to help focus sound from the diaphragm.

In March, 1926, Edison finally offered the public an alternative to the venerable standard reproducer. It was called the “Dance” model, and of the four, it is the most visually distinctive, because unlike the other three models it has a large flange atop the diaphragm housing. I'll go into more detail about it in a subsequent article, but suffice it to say that the dance reproducer incorporated two major changes: first, its floating weight was significantly larger and heavier than that of the standard model, and second it put both the stylus bar and diaphragm under spring tension. As you might guess the intent was to generate enhanced volume for dance music played on Edison phonographs.

Just as Brahms, once he finished his first symphony after years of delay, wrote three more in relatively quick succession, so Edison, having released the Dance reproducer after years of offering only the standard reproducer, added two more within the space of a few months. First, in October 1926, came the Long Play reproducer, specifically designed for Edison's new long-playing diamond disc records and included as standard equipment with a line of special phonographs for playing them. The Long Playing reproducer is easily recognized because the word "long" is engraved in the diaphragm housing, and it should not be used to play standard diamond discs. The long playing discs were a technological marvel for the middle 1920s, and in fact they remain so today: in the larger 12" size, they played for 20 minutes per side at 80 RPM. To achieve this extended playing time, their grooves were pitched at a constant 450 threads to the inch. By comparison, a standard diamond disc's groove pitch was 150 threads per inch, and a modern LP microgroove, although variably pitched, typically will top out somewhere around 250. Needless to say, the Edison grooves were extremely fragile, and the Long Playing reproducers accommodated them by featuring a much smaller, lighter floating weight than those of the other models. Naturally, they also had smaller diamond styli to fit the minute record grooves. Unfortunately for Edison, the long playing records were a commercial failure. Those fragile grooves did not hold up in typical household use, and at a time when the public fashion was for ever greater volume and bass, the light-tracking Long Playing reproducers actually developed less of both than their standard counterparts. Finally, because of the technical challenges inherent in their creation, the long playing discs were all dubbed from standard records, generally as what might be termed “recital programs”: two featured groups of violin encore pieces, one played by Albert Spalding and one by Carl Flesh; one was a collection of songs by Edison's favorite soprano, Anna Case; one was a collection of short “dinner music” salon pieces by the Hotel Commodore Orchestra; and so on.

April 1927 saw introduction of the last Edison disc reproducer, the New Standard, later renamed the Edisonic. This model retained the heavy floating weight and some of the spring loading of the Dance reproducer but in a way that eliminated the Dance reproducer's flange atop the diaphragm housing. The New Standard/Edisonic was issued as standard equipment when Edison finally and belatedly adopted electrical recording, which had revolutionized the rest of the industry. For more about Edison's hesitant path into this new technology and the company's associated equipment, I'll refer you to my recent TNT-Audio article featuring a shootout between Edison's and Victor's machines of the period.

I suppose a word is in order about the finishes that Edison made available for these reproducers. The photo at the beginning of the article shows the three most common: satin gold, polished nickel, and antique bronze. The gold finish was reserved for the more expensive, top-end, “laboratory model” machines, like the one heard in the companion video (about which more below). Middle-of-the-line and bottom-end machines got nickel hardware. (In this practice, Edison was hardly unique; Victor, for instance, did much the same thing with its Victrolas.) In the middle 1920s, with the introduction of the Long Playing Consoles, Edison began applying a more subdued finish, antique bronze, as seen on the Edisonic and Long Play reproducers in the photo. Early on, one other finish was available, issued as standard for reproducers included with a few of the very first models of diamond disc phonograph. Known as “anodized,” it appeared as a dark bronze colored body shot through with wavy copper-colored lines. An example appears in the photo to the left. This distinctive finish, also found on the hardware of some early Amberola and deluxe level open horn cylinder players, disappeared very quickly after the introduction of the disc phonograph line and, unlike gold and nickel, is seldom encountered today.

A Comparison. Following the example of Julius Caesar, who divided Gaul into three parts, I am offering a tripartite review of Edison's disc reproducers. In a companion video to this one, the first, you can hear each of these reproducers in action and get a feel for yourself of how they perform. The succeeding articles will include similar videos. In each, you can hear a single recording as rendered by different reproducers, representing three general categories of musical content. The future ones will offer dance music, first acoustically and then electrically recorded. The present video offers acoustically recorded orchestral music, and it differs from the others in including music from one of the rare long playing discs, played with the Long Play reproducer. The remaining reproducers play the source recording from a standard diamond disc.

The Music. Heard in the video is an excerpt (“the fun part”) from The Dance of the Hours, the popular ballet segment that ends Act III of Ponchielli's opera La Gioconda but that is probably better known as a ballet of hippos, alligators, elephants, and ostriches in Walt Disney's animated film Fantasia. The recording was made on November 9, 1917, by the “American Symphony Orchestra,” the name the Edison company assigned to its house ensemble. All Edison's recordings of classical and light classical orchestral literature were issued under this name; the label never attempted to record established orchestras like the Chicago Symphony, New York Philharmonic, or La Scala Orchestra, as did Victor, Columbia, and various European labels. Note that in general, at that time claimed involvement of a “name” orchestra was more nominal than actual: with the acoustic recording process, the ensemble was limited to such much-reduced forces as could be crowded around a recording horn, and the music would have been rescored to improve registration by the relatively insensitive recording gear. More often than not, scores were similarly truncated to fit the limited recording time of 78 RPM sides, but here Edison offered the piece complete, spread across two sides of a single standard diamond disc and—without break, of course—dubbed as the last of three selections on one side of one long playing disc, the other two being Suppe's Poet and Peasant Overture and an arrangement for flute and clarinet of a duet from Bellini's opera Norma. The standard issue was record no. 84038-L (Edison, always a little different, denoted sides -L and -R rather than -A and -B or -1 and -2); the long playing issue was 30002-L.

The Equipment. Playback of these records is on an Edison model C-250 (“Chinese Chippendale”) diamond disc phonograph. Introduced in December 1915, and redesignated the C-19 in April 1919, it was the best seller of Edison's top-end machines. As a marketing ploy, the company designated such machines “official laboratory models” and even affixed to each a decorative medallion stating as much. When first introduced, Edison's disc phonographs had a variety of motors and horns, but the company soon settled on a more systematic and efficient approach. With few exceptions, the line ultimately comprised three broad classes: the smallest, bottom end machines, with the smallest of three horns; a group in the middle, with an intermediate sized horn; and another at the top, with the largest horn. All had the same reproducer and mechanical feed playback mechanism. They also had the same motor, except that with one exception the top-end machines added a second spring barrel to it. Thus, the only difference between machines in a given class was the cabinet design.

The C-250 heard here dates to around February 1918, predating introduction of the long-playing records and reproducers and hence originally unable to play them. Edison, however, was always mindful of what we today call “back compatibility” and invariably offered adapter kits for older machines when introducing new features or products. The present C-250 has been fitted with just such a kit, which would have included a new set of drive gears for the mechanical feed, a selector to choose between gearing for long play and standard discs, and a Long Play reproducer. So modified, acoustically and mechanically it is identical to the best of the dedicated, and commercially unsuccessful, long-playing consoles Edison introduced together with the long-playing records; only the cabinetry is different. It has a two-spring motor capable of playing more than 20 minutes on a full winding—as required for the larger, 12" sized long playing discs—and the largest horn Edison offered for disc playback at the time. The “long-short” selector switch for choosing between long and standard records is visible in a photo above. Considering its antique bronze finish, the Long Play reproducer here probably was issued with a Long Playing console phonograph, not as part of a kit. I have a similar one in gold, which probably was a kit issue. It has a modern replacement stylus, however, whereas the antique bronze one has an original Edison diamond; whether for that reason or some other, it's the better sounding alternative.

The procedure. I followed much the same technique here as in the Edisonic-Orthophonic shootout article referenced above. Briefly, I set up my Zoom H1n recorder on a tripod around 6 feet away from the machine and my video camera on another tripod immediately adjacent to the C-250. To preserve relative volume, I proceeded to record all the samples in a single take, yielding a single file, and after trimming extraneous sound and normalizing what remained I broke the audio file up and substituted audio from the Zoom recorder for the distorted, limited audio captured by the camera's onboard microphone.

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[1] - The one major exception among universal players was Brunswick's Ultona reproducer and tonearm system, which in its most elaborate form incorporated two diaphragms and could be rotated in various ways to play vertical Pathe, vertical Edison, and conventional lateral records. In its vertical cut positions, the diaphragm of the Ultona was horizontal, although it would be vertical in the usual fashion for lateral cut records. For more information, including photographs showing the Ultona's range of adjustments, see here. Some machines, particularly Pathe's Actuelle and Diffusor models and HMV's machines with Lumiere pleated diaphragms, substituted large paper cones or resonators for the more conventional diaphragm-in-reproducer-plus-horn model, but these were exotic players with limited presence on the market.

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On an Overgrown Pathé

The Edison Disc Reproducers: A Comparative Survey

Part I: Acoustic Orchestral