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#9. A BRIEF HISTORY OF STEREOPRAVDA SPEARPHONE PROJECT DEVELOPMENT IN PICTURES
































As the below history is brief, I’ll try to stay brief.

More detailed discussion of this project’s design aspects can be found here:

http://stereopravda.com/upload/iblock/978/97801afc884956320083a1237cfe7ffb.pdf

The history of the SPearphone project started in 2009 with my desire to improve the sonics of my own pair of the venerable Etymotic Research ER-4S.

With 20+ years spent in High End Audio, and being fully aware of its “tweaking” streak, it was obvious to me, that the earphone is very special, and that the original product’s performance can be improved.
My first attempt was pretty obvious: to insert the ER-4 innards into a better chassis.
A friend of a friend milled the appropriate part from titanium.
A few weeks later I tried to shove the modified earphones into my ear channel mold to see what’s going to happen.
As another simultaneous ER-4S “mod”, I started to use Chris Sommovigo’s (whose Stereovox/Stereolab lines of audiophile cables I’ve been distributing in Russia for many years) first generation “tonearm cable” as my earphone cable.

With all the problems of ear mold listening – please, see my previous blog #8 – the more I would get rid of the mold material, and the deeper I would push the modified ER-4S along the ear channel, the better the sound I would get.
In February 2010 I ended up with just a small chunk of mold material in the back of the first prototype (pic.1, the spring was an intuitive and cheap substitute for the ear mold to follow the curvature of the ear channel while moving the prototype deeper and deeper inside it).
While developing that first prototype, the initial experiments with earphone tip material, its shape and its positioning lead to the same basic configuration that was confirmed, time after time, through a lot of later attempts to try to reconsider it.

And, by the way, I DID try an ear channel mold approach on numerous occasions later, but, with sonic priorities in mind, always with no avail (pic.2).
Building that first prototype taught me how important the “on-axis” positioning of the driver is (towards “overall” ear channel propagation direction), and how even a slight “off-axis” misalignment with this vector would substantially decrease the sound quality.

A few months later, armed with that deep insertion technique of ear monitor deep positioning and the correct ear channel acoustic isolation, I came up with an idea to get rid of the ER-4S chassis and to see what a “naked” driver is capable of (pic. 3).
As that experiment happened to be very promising, I started to audition numerous drivers from the various Knowles lines to see what their sonic signatures are.

In May of 2010 an obvious development came – instead of using a single driver I tried to use a couple of drivers (from the ones I selected as the best on their sonic virtues during my preliminary auditioning) (pics. 4 and 5).
A couple of months later I attempted again to look at ear channel sealing techniques, and the original “second bend” one proved its superiority over anything else I have tried out (an example of those failed attempts is depicted on pic.6).

Six months’ worth of various prototypes’ auditioning later, in December 2010, a Knowles CI driver was mobilized to help.
Also, Chris Sommovigo supplied me with a sample of his second generation $150К “Caliburn” tone arm cable (pic. 7).

A couple of months later one more driver was added to “the mix” (pic. 8 ).
The second generation earphone cable was replaced by a much more robust Teflon-tape covered third generation one in June next year (pic. 9).

While I’ve been tested one prototype after another Chris’ forth generation cable came up a few months later (pic. 10). But it was too sturdy for my application.

Picture 11 shows one of the prototypes built with Chris Sommovigo’ fifth generation version of the earphone cable (including carbon fiber filling).

In the next couple of years more than twenty earphone prototypes were built, some of them have been using up to sixteen (!) drivers per channel.

Speaking of which, if we would fast forward to October 2015, when I spoke with Jerry Harvey at the annual Can Jam in Denver, while he’s been auditioning our StereoPravda SPearphone SB-7 earphones, there he mentioned that SPearphone’s “voicing” is great, but there is nothing new as he’s been building very similar BA-driver arrays prototypes when he started (pic. 12).
Also he told me that while we are using “old” drivers in our models, there are new, and better, BA-drivers available. Here I am ready to disagree with him: if he meant by the last statement new series like Knowles TEC/DTEC, then, sonically, during my initial auditioning in 2010 they didn’t impress me at all. If he meant Knowles GQ series, it’s simply a combination of two “old” drivers: ED-series “woofer” and “old” WBFK-series “tweeter”.
Possibly, he could mean some new products from different, than Knowles, manufacturers (like Sonion). But I seriously doubt that gregarious differences are possible, otherwise I would see some “new” products from such an industry leader as Knowles (the ones I exclusively used in my prototypes), which would also demonstrate some breakthroughs in sonic qualities.

In any case, Jerry Harvey confirmed what for the last many years I’ve been hoping to hear from somebody like him: the “voicing” of our earphones, that is their overall sound, is very good.

As I see it now, when building those very similar first prototypes Jerry has been building them from a completely different perspectives than mine, and at the fork after the first prototypes stage, in correspondence with the available technologies, we’ve taken two different roads in two different directions: he hit the road for the widest commercial acceptance for his earphones, while I, without prior concern for the commercial viability of my efforts, hit the road for my earphones’ highest sound quality.
Only after reaching a certain sonic elevation plateau I saw some commercial opportunities, which are based solely on our products’ sonic achievements, and which, however narrow, we are fully content with (please, see my previous blog #8 for more thoughts on this subject).

In January 2013 Chris Sommovigo came up with his seventh generation cable.
Using a rubber core helped a lot in obtaining the cable qualities I needed: a fantastic sound, on the one hand, and a stable, during a typical usage, cable configuration, on the other (pic. 13).
It became clear that at the moment we were very close to the completion of the cable project: the only thing Chris had to do was to arrive at the appropriate technology for the cable’s outer jacket.

The next year and a half were spent refining designs of some better SPearphone prototypes (and unsuccessful attempts to design and to build some quite extraordinary “onboard” and “outboard” passive filter networks).

In April 2014 the StereoPravda SPearphone “Second Bend” series of earphones was finalized with Chris Sommovigo’s eighth generation Teflon/Kevlar outer jacket earphone cable.
We decided on three models in our SPearphone line (pic. 14):

http://stereopravda.com/shop/

During the same period our first DAC/Crossover/earphone Amplifier (DACCA) sample unit was fully designed and built by Alexei Malanin and all its tests were successfully completed.
All our expectations about the sound of our earphones paired with DACCA and its adjustments capabilities were fully met.

By January 2015, after “cleaning our act” (pic. 15), the SPearphone project started to appear to me as a viable commercial opportunity.
We came up with an appropriate infrastructure to build and market this line of products.
We also re-launched our web site:

http://stereopravda.com

The first public response demonstrated a great interest in our products (as an example, a famous record producer Rick Rubin requested us to send him a pair of our SPearphone SB-7 for his personal use – pic.16).

In July 2015 Gary Reber, the editor-in-chief of Widescreen Review magazine published an extensive interview with me about the SPearphone line of the products:

http://stereopravda.com/upload/iblock/978/97801afc884956320083a1237cfe7ffb.pdf

To conclude this brief history, I’d like to mention that those six years were a combination of excitement over better and better opportunities to enjoy great music, persistence to overcome all sorts of technical and other obstacles, belief in the content of what we were doing not only for ourselves but for others, and, last but not least, a great deal of pure luck.

I’ve been not only lucky in having a good deal of real estate within my ear channels, which allowed me to comfortably put and to test a “silver bullet” BA-drivers’ configurations next to the anatomic “Second Bends”. To stumble upon that “silver bullet” solution was a huge luck in itself.
If I were not persistent enough, I could easily missed it.
On the other hand, I could waste even more efforts, and still miss it…

Also, I’ve been very lucky to apply my induction methods while having access to various resources, including time, money, advanced technical expertise help provided by people whom I personally know, and, most of all, great friendships.
Some of those close friends, whose help in this project I can not overestimate, were mentioned in this story.

Nevertheless, the biggest luck in this project was that I’ve been lucky enough to graduate from the High End Audio’s school of music listening just in time to join the ranks of the first pioneers, who recently started, applying their knowledge and experience that they’ve got in that school, coupled with the latest advances in new technologies of music delivery, storage and playback, and, also, substantially increased batteries charge capacity, to build a bridge from the high performance home audio, as we knew it for the last forty years, to the just arising portable version of it.

And I see this transition as pending as the recent transition from using phone land lines to using cell phones.

That’s why, as a long term audiophile, who cares a lot about the future of High End Audio, I could only dream about being a part of such a revolutionary change.

03.03.2016 // Author:  (Bigmisha) // Number of views:  1220

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