Conrad Johnson PV-10A mod experiences?


Has anyone had experience performing a mod on the CJ PV-10A? I'm fond of this preamp, it has that wonderful tube openness and sweetness for harmonics. However over the past 6 months as I've delved into PC audio and DAC improvements, I've come to realize two things about it

1) its slow on transients
2) its dynamically compressed.

I'm using Mullard NOS tubes throughout as these seem wonderfully detailed with excellent base.

Since the preamp is built like an engineering prototype (overbuilt)my gut hunch is that some caps have aged (circa 1993)and need replacement, specifically the white CJ caps
and am thinking about replacing them first with Multicaps.

Wondering if anyone has experience trying to revitalize a PV 10A?
128x128davide256

Showing 1 response by countryjazz2

When my PV-10 (that I had for 17 years)needed repair (a tube arced and blew it out), I sent it to Bill Thalmann at Music Technology. IN addition to the repairs, I had him do his mod package (which included replacing the original caps with "auricaps", among other changes). The pre did sound more accurate and "faster," but it may have lost some of the ambience and warmness that it had originally. Unfortunately, I don't know if it would have improved over time, because after a few months, the same thing happened again (probably my fault, I put in a tube I shouldn't have). Unfortunately, Bill never responded to my E-mails after that. I couldn't afford to have it fixed again, so I sold it as is, and went back to solid state (Emotiva, with a Yaqin CD-1 tube buffer). Personally, I was never happier with my CJ than when I had a Bugle Boy and an RCA triple mica black plate 5751 in the line, and Telefunkens in the phono. The mods made a difference, but I was always happy with the original sound of the PV-10. (great midrange and phono stage). I've always had a SS amp (Adcom, then Classe).