Edison Diamond Disc New Diaphragm Test

[CarlosV]

Having amassed a large collection of diamond discs, and being consistently disappointed with the underwhelming sound from all machines I own (a Schubert, a Hepplewhite, an Army & Navy and a B80), I ordered new diaphragm designs made by fellow forum members, one True Tone from Larry and a Figure 6 from Wyatt. I report below the results of my listening tests, with no sound clips, because there is no way to convey high fidelity sounds via you tube.

I installed each diaphragm on a dedicated head, each with a good diamond tip, and followed the basic instructions from each designer. Installation was straightforward for both, and the only adjustment necessary is the torque of the retaining ring, which I did by trial-and-error, playing the same part of a record and progressively tighening the ring until no blasting or effects from shattering are heard.

I used the Schubert as test machine, as it has the largest horn among the ones I have, and a number of different records, instrumental and vocal, opera arias, fox trots, instrumental pieces etc, and the first and main conclusion is:

- Both modern diaphragms bring a VAST improvement in the quality of sound. The muddled quality of the vintage ones is replaced by a clear reproduction. I utilized as comparison four original heads with their diaphragms, and all four exhibit a consistently subpar reproduction.

Comparing the True Tone and the Figure 6, my experience is:

- The Figure 6 output is louder than the True Tone

- The frequency response of the Figure 6 has a peak around the clarinet/soprano range, which causes it to produce a so-called "bright" sound

- The True Tone has a flatter response over the spectrum, and I could not identify any resonance when playing the various records

- The True Tone reproduction allows identification of background instruments like a banjo and a piano in a dance band record, while the Figure 6 somewhat masks them when the front instrument is a clarinet or a trumpet

- Both diaphragms reproduce well the human voice, and I did not discern a difference when playing a tenor or baritone solo


In summary, for the fellows who enjoy playing Edison records, I strongly recommend to replace the vintage diaphragms with one of the modern ones made by our forum members. My personal preference is for the True Tone, due to its flatter spectral response, but the casual listener may find the Figure 6 more impressive due to its loudness and brighter reproduction.

My next experience will be installing a True Tone on my Opera, which Larry kindly agreed to make. I have high expectations for sound improvement, as it is essentially the same design as the Edison diaphragm scaled down.

[marcapra]

Carlos, Thanks for reviewing these two diaphragms for us Edison Diamond Disc collectors! The both sound very good! Marc.

[CarlosV]

Carlos, Thanks for reviewing these two diaphragms for us Edison Diamond Disc collectors! The both sound very good! Marc.

I hope my review will be useful, Marc. I was really impressed by the improvement in reproduction. Edison may have invested a lot of resources in the design of the original diaphragm, but the materials available today, combined with the patience and persistence of our fellow hobbyists, outperform the original by a significant margin.

[audiophile102]

Carlos, Thanks for reviewing these two diaphragms for us Edison Diamond Disc collectors! The both sound very good! Marc.

I hope my review will be useful, Marc. I was really impressed by the improvement in reproduction. Edison may have invested a lot of resources in the design of the original diaphragm, but the materials available today, combined with the patience and persistence of our fellow hobbyists, outperform the original by a significant margin.

Thank you for the review. My A250 sounds wonderful thanks to Larry and his True Tone diaphragm. I bought an Edison Electric diamond disk in excellent condition and I was blown away by the frequency range and clarity.

[drh]

Carlos, Thanks for reviewing these two diaphragms for us Edison Diamond Disc collectors! The both sound very good! Marc.

I hope my review will be useful, Marc. I was really impressed by the improvement in reproduction. Edison may have invested a lot of resources in the design of the original diaphragm, but the materials available today, combined with the patience and persistence of our fellow hobbyists, outperform the original by a significant margin.

Bear in mind, too, that Edison's materials now have about a century of age on them and probably don't perform the same way they did when new. What would be really interesting would be to hear a diaphragm newly manufactured exactly as the originals were and from the same materials.

It would also be interesting to hear Boito's Mefistofele as performed at its disastrous premiere, reflecting the composer's original conception before subsequent revisions.

Neither one is very likely to happen, alas.

[marcapra]

On the other hand, I have purchased an NOS Edisonic reproducer that sounds as good or better than a modern replacement.

[larryh]

On the other hand, I have purchased an NOS Edisonic reproducer that sounds as good or better than a modern replacement.

You are fortunate to have found one that still plays well. In many years of owning various original diaphragms I had never heard an Edison Record without distortion or weak sound. My guess after some work with it myself is that the shellac as it ages becomes way less flexible and in the oldest states usually brittle and falling off in parts. I recall making some early versions and when they were almost new sounded wonderful, but if you went back to them in a few days the sound changed dramatically for the worse. I never could figure out how to prevent that. He was lucky to have hit the right combinations and parts. Every tiny change in a design can result in noticeable differences in the sound quality.