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I usually do not cruse across DIY forums unless someone folks about me. Here it was - at some Russian DIY site they translated my article “6C33C survival guide” that made me to see what they have in there. One article from their site attracted my attention. It was from spring of 2010 by somebody called AlexD. He described how he built his 3-stages PP amps with 2N23P-6E6P-6С41С. I do not know if I like this amp but what this amp has interesting was the power supply – he use pulse power supply from computers but hand rebuilt. The article in Russian and to see the articles you need to be registered (stupid thing to do in my view) but the images are clickable and can get bigger even for guests.

http://datagor.ru/amplifiers/tubes/1209-moshhnyjj-rr-na-6s41s-s-pitaniem-ot-impulsnogo-bp..html

I do not know if I am a fan of Pulse Power Supply but in context of what I am going now with PurePower it made me to think. I do not know why a properly working PP2000 produces such a positive sonic effect comparing to the linear regenerators that out much less distortions and noise.  So, frankly I would not mind to hear an amp with Pulse Power Supply built explicitly for a given amp. It might be interesting.

You see. We use a regenerators like PP2000 or PS Audio’s Power Plant to reshape the sinewave and we are under presumption that crooked wave is not good. Then we give to amp a perfect wave and it is still not good sounding – think about Avicenna or Power Plant regenerators. In contrary the older version of PP2000 did sound very well despite that it had much higher distortions of sinewave. So, let assume just for mental exercises that the quality of sound is absolutely independent from the sinewave deformation. Let also assume that not the fact of deformation but the outcomes of deformation affect sound. For instance if sinewave is clipped – a common problem with AC lines then the act of clipping itself injects a huge amount of HF noise into the line. The noise is very higher harmonics of unclipped signal, so we have 4th, 11th, 23th, 34th harmonics, they are way attenuated but they are there and they are in ULF…. Then we have Pulse Power Supply…

According to the Nyquist–Shannon-Kotelnikov sampling law:

http://en.wikipedia.org/wiki/Nyquist%E2%80%93Shannon_sampling_theorem

any switching devise is able to reproduce no higher frequency then a half of sampling rate. It means that the device like PurePower PP2000 that runs let sat at 20kHz of sampling rate is absolutely immune to any line noise that is higher than 10KHz. Any higher frequency noise just falls between the pulses of the switching device. So, purely hypothetically: if the quietly of sound from a properly operating PP2000 derives from the fact that it is pulse but not from the reshape sinusoid then why a Pulse Power Supply on SET amp with no regeneration would not do the same trick?

What I would like to see is somebody makes a SET amp with linear PS and then substitutes it with Pulse PS. Of cause it might be zillion reasons why ether linear PS or Pulse PS would not sound good but I would like to hear not the absolute performance but to hear if the change in sound would be in the SAME strategic direction as the properly operating PP2000 takes sound to. At this point I truly know what to look for in sound and how identify the PP2000-like contribution to sound. So, if someone in New England would accommodate Pulse Power Supply for your SET then let me know and I would like to hear it “before” and “after”.

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