R22 is nor R but K

Here are some commentaries regarding my “End of Life" Phonostage.

The name of this phonostage derives from many factors. I am forty, winch it more or less a half live and in the first half I was playing a lot with different audio toys. The last 10 years I played more or less aggressively with phonostage as the RIAA stage were some kind of bottle neck of analog reproduction.  However, what I discovered that regardless what I did with RIAA filteres I always returned to a combination of Expressive Technology magnetic and EAR 834 phonostage. For whatever reason that sound to me is the most comforting of anything I heard or can imagine in LP sound. It has better sound then just good sound – it has some devilish musical magic that is so difficult to “get” in audio. So, from one side I had a very satisfying audio result. From another side I have a desire do not do anything with my references phonostages anymore (I have found a good “second rank phonostage” for my none-reference arms and will play with in later). From the third side I have a materialistic and rational presumption that it will no ever be any more interestingly sounding step-up transformers (available within my reach) then the Expressive Technology ET2 transformer… So, considering that I look forward to retire from my “reference” phonostage interests I decided to render a short “end of the RIAA desire” project…

Then, I got a phone call. It was a friend of mine, an audio guy, who was sick and who was kind of on his way out. Talking with him I got inflicted not by the sense of our own mortality but rather with a feeling of abnormal ratio that we practice on audio – the ratio between exercising of results and preparation of the results. We, at least some of us, spend a large amount to time and efforts to discover specific areas of sound understanding but the sad truth is that the time we invest in audio education of ourselves has a “price tag”. This tag is a removal ourselves from the experiences of actual consumption of musicality for the sake of learning about audio, or learning the rules of audio consumption via a playback.

So, I decided to end with it and I feel that I know in analog enough in order do not need to know or to care about anything else anymore. It is not that my analog setup is good or bad but rather it is about the fact that my results with analog sound are sufficient for me in order me do not invest more time or efforts in order have a desire to have better Sound. I recognize that the second part of my 40-years I have no interest to think that there is anything else out there in analog world that attracts my craving to try it. I understand that what I say is not the factual statement but it is rather my sentiment of self-delusion but I agree with myself in this delusion. Thinking about it all a few month back here is where the idea of “terminally beautiful phonostage” came to the existence. The dying friend proposed a good idea: his death will stop his peruse for his version of “better sound”, so I figure what why wouldn’t  I  declare the death of my analog desires right now, while  I still have 40 years ahead of me for actually practicing my analog expertise and practicing  my analog accumulations.

So, the “End of Life Phonostage” is my version of absolute RIAA references after which egos and sound have no needs anymore to be enlarged. I do not suggest that that the “End of Life Phonostage” performs better then other hypothetical phonostages I just state that I do not look forward anymore to answer this question to the rest of my audio life. So, I do not consider the “End of Life Phonostage” as a “Death phonostage” as it was proposed in the beginning of the thread but I rather feel that the “End of Life Phonostage” is a birth phonostage, the birth for a new level of audio practicing awareness.

Paul S wrote:

I have had +/- the same thoughts about gear for some time....

Hello Romy

Reggie wrote:

Did you take courses in electronics and mechanical engineering or have you learned yourself outside of a structured environment? I am very interested to become proficient in working on/modifying my own electronics. I would enjoy spending time at the workbench such as the one pictured above.

Nope, have no structured training but juts a respect and discrimination to results, common sense and an opportunity of asking right questions. What I would like to note is that I have no specific pride of even interest in doing my own electronics and if I have somebody why would do it for me I would joyfully not have even a solder gun.

Reggie wrote:

Reading many posts on your site has caused me to think about my system. I'm facinated by horn systems and have heard several that were compelling in key respects, the ability to use a DSET such as your Melquiades amp being one.

Reggie, I would disagree. DSET is not a key in horn systems. DSET is a way to fight with intrinsic limitation (or I would say complication) of SET topology. Horns by nature do not need DSET as they are harrow bandwidth devises…

Reggie wrote:

One the subject of a 'final' phonostage, my own is one of the three MFA Systems MC Reference prototypes built for CES in Las Vegas.…This particular phonostage has the magic you talk about.

I never heard this phonostage but if it has that “it” then it is good for  them.

Reggie wrote:

Romy I cannot upload the images. I tried using the 'insert images from gallery' button. Can you tell me how to do this correctly?

I spent a bigger part of day today to finish the “End of Life" Phonostage, there were many things to do but it is now over. Done! Complete! Amen! I it closed up and sat in it’s permanent place.

A few observations looking back. First, I spent a LOT of time trying to fine tune the RIAA curve. I use the test LP with 20-20K sweeps. I use Jim Hagerman’s contra-RIAA little tool, driving the RTA and scope from generator. I use my Wavelab’s phenomenal FFT meter driving the Phonostage into Pacific Microsonics analog-to digital (this A/D calibrated mind-bogglingly well). I usually use the Wavelab’s FFT and Phase meters to help myself to setup cartridges – very covenant. Anyhow, to my displeasure I learned that  the contra-RIAA devise was slightly off at HF, so I end up not to use it and used other means.

In the end of everything I was able to get very nice response. The response is nice and flat with 0dB at 18.1Hz and 0dB at 15.600Hz. It has plus 0.2dB from 1500 to 3500 which I feel is not a big deal. (Juts for my future reference: the values of the feedback capacitors have without de-soldering capS from the circuit are: 110pF= 136.2pF and 330pF=372pF)

 I found a very good grounding schema and the self noise this corrector of 26db+48dB=72dB gain is better than good – it has absolutely no noise. The previous adaptation had no problem but this one took noise even further – there is no difference for the system between CD input and phonostage input, and do not forget that we are taking about 109dB sensitive system.  I presume that my new construction techniques (mounting everything short point-to-point on a think copper plate that used as a ground terminal) do help. What I also detected over the second part of day playing the corrector that it looks like the gas regulation helps with good with electricity. Apparently the gas tubes shunt all power line dirt – a promising sign.

Sonic results. It is hard to say. I feel that there is no sonic difference between my former version and the new one, the new phonostage  is too fresh, the caps, the PS, the disturbed Dominus cables the total assembling - perhaps I need to return to the subject of sound after 500 hours. The new phonostage has the following changed compare to the former one:

1) Fix biasing on the second stage instead of the former automated
2) Different filament and anode PS, the anode supplies are gas regulated.
3) Better construction techniques  (the former version was my very first DIY Audio attempt since I began practicing the  US version of High-End Audio)
4) V-Cap coupling capacitors between the first and second stage
5) More immediate connection between the ET2 transformer and first grid

I did not study or observed the incremental changes, let see how it will turn out all together.

Preliminary conclusion: very good. It looks like the essence of the ET+834PT was not lost (that what I was afraid and this is why I built a new corrector and kept the original intact – just in case). The new corrector did not developed it’s full bass yet but I know the Nichicon caps and the disturbed Dominus – it shell come later. All together the sound as I expected – three is nothing alarming at this point. Some unique ET+834PT quietly are still there. For instance the ET+834PT is the only know to me phonostage that is capable to play  (if needed) without HF.  I mean any good phonostage I tried threw very high quality HF, demonstrating that analog HF might be very-very good. Only Boulder 2008 phonostage was a minor exception that was able to throw non-presumptuous HF up to a degree. The ET+834PT takes this approach to extreme – it has no HF at all and it pitch HF into the game ONLY when it is necessary. You listen it and it feels at beginning that there is not enough HF but you add .5dB and realize that it is how live Sound sounds. There is no HF in live sound; there is Space but no HF itself. ET+834PT does the necessary HF’ space tricks without actually making HF themselves. I can go on in many other specific distinctive characteristics of the ET+834PT but it is not my objectives at this point. The important is that the new procurator looks like preserve them all – God bless the smart Tim de Paravicini’s design of amplified Miller capacitance and feedback to high impedance.

The "lack" of HF is definitely one of the wonderful things that makes one think of spending 30K on a phono stage.  Glad to hear you are "suffering" a similar "dirth" of HF [noise] with your DIY corrector.

I wasn't going to say anything, but I wondered up until I saw this "finished product" photo if you planned to run the 12AX7s horizontally...  That would have been "interesting"...

My "modern" Teflon composite caps did not take long at all to establish themselves; nothing like the "premium" electrolytics, which not only take a long time to sound decent but they also "revert" if you don't run them for a while.

Do I remember that Tim d' P. also likes to use one twin triode tube for two channels?  I am "iffy" on this conceptually; never tried it.

I know you are all stoked with FM benefits for some time now; but surely the musical treasures on vinyl are enticing, not to mention the potential?

I have also read your thoughts on VTA/SRA, but if your corrector is "articulate" then you must be pretty much stuck, needing to get it fairly close?


Best regards,
Paul S

OK, here are some follow up thoughts after the completion of the project. I am sure I will burn it for a month or so. I think everything will be fine, I do not expect any issuers technical or sonic. The way how the entrance to the corrector done it is very easy to replace the 4 cable from 4 arms without replacing the cables. As I told I did found a very interesting “second phonostage” (very convent one) that I was planning to use with my other arms but if it is so convent to flip the cable I wonder if I go for the second phonostage. I still have my former 834PT and the 7788-7721 phonostage available, all performing perfectly fine … later on I will decide if I willing to use them.

There is one area that I would like to explore with my “End of Life" Phonostage after it will settle down. The very smart fist stage in there will be stay as is, also I have no interest to experiment with second stage. The last stage is just a cathode follower. In my ultimate buffer experiment I never was able to get a good transparency from tube buffers, so I am intending to put there (as an experiment) a transistor instead the last 12AX7. I am not planning to change anything but juts to take a male 9-pin tube socket, solder in there a transistor that is able to care 300V and juts plug it and play. It is possible that with SS output buffer I might get different result. What kind result I would like to get? Sonically I can’t at this point to identify what I would like to get but measurements –wise I would like to drive the low range to sub 8Hz at 0dB. It is not that my hands are itching but I feel that at line level SS buffer shell do better than a tube…. If someone know any good sounding low power (5-15mA) transistor at 300V-350V then please let me know. So far I was proposed MPSA42, ZTX458 and suitable but too powerful MJE340. As a reader of my site suggested:

“The NPN will reduce the output impedance => will affect the Riaa feedback increasing the gain by ~1db@20Hz and ~0.5db@50Hz (in your setup will be quite noticeable). A quick and dirty remedy is to add a resistor (1k5-1k8) in series with the emitter of the NPN. Although this could be useful to reveal the sonic properties of the NPN it may also defeat the trouble”

I still consider the options how to make the experiment with buffers substation clean and methodologically kosher. Sine I have absolutely no knowledge at SS any recommendation are welcome via the site or direct emails.

The SS out does calm/quiet/clear things considerably, but there is a price for that clarity, as I have reported.

You probably already looked into JFET?

Do I "remember" that you had a stash of exotic adjustable air-core caps?  As you can tell from the question, I have not tried to run the math, but would the "trim-able" cap give you enough range to dial in the network?

The last time I ran into this, I think wound up with Audio Note tantalum R, which can do "hard" better than wire or carbon comp.  Vishay was "too much" there, as I recall, like on plates.

Best regards,
Paul S

Paul S wrote:

Do I "remember" that you had a stash of exotic adjustable air-core caps? As you can tell from the question, I have not tried to run the math, but would the "trim-able" cap give you enough range to dial in the network?

Brian Clark wrote:

I have some ZVN0545A mosfets here for exactly that purpose of replacing cathode followers. You may like to try this starting at 2mA (250V supply, 125k biasing resistor).

Brian, and how do you find your MOSFET behaves compare the 12AX7-based cathode follower?

Brian Clark wrote:

Did you or Dima try Soviet SSG silver-mica for the first coupler? I am using 0.175uF items for excellent results though I haven't compared to teflon.

Nope I did not try them. I have 5-6 different versions of silver-mica though and I prefer air caps. I do not know what Dima tried. He has the same corrector with Ocean State’s air caps only in place of the first 12AXy he uses Russian nuvistors

Brian Clark wrote:

The 834P circuit is not designed for low distortion (probably why Guy dislikes it) but for "listener-friendly" natural harmonic decay. I guess that accounts for the magic….

This is big question but I would have a lot of to say. I do not think that 834P circuit is designed for any specific distortions.  I understand “distortions” differently.  You might read my Macondo Page that gives an idea how I see distortions….

Romy the Cat wrote:

Brian, and how do you find your MOSFET behaves compare the 12AX7-based cathode follower?

I have 5-6 different versions of silver-mica though and I prefer air caps. I do not know what Dima tried. He has the same corrector with Ocean State’s air caps only in place of the first 12AXy he uses Russian nuvistors

I do not think that 834P circuit is designed for any specific distortions.

deemon wrote:

Brian , I never tried SSG cap in phonostage . SSG has a good reputation ..... but I'd prefer teflon for coupling . Mica caps , even good ones like SSG , seems too "bright" for me , but teflon sound pretty neutral .