On 12/22/2009 I posted my PAS-3X enhanced rebuild on Audio Asylum forum.
I imagine VTA preamps etc are much superior sound----but they are not really a PAS.
If I want really superior sound from my PAS-3X then I run the tapeout thru rear-mounted Noble 10K stereo log pot into ST70.
I had decided against installing such a pot into ST70.
I had replaced the sides and top with 1/8in mirror glass for mid-century appearance and EMI rejection.
So in April 2022 I went inside and did the following:
replaced all coupling caps with K40Y-9
installed late-50s Sylvania 12AX7A (7025) into PC-5 linestage
installed Raytheon/Balwin 12AX7 into PC-6 phonostage
removed all 120VAC outlets on rear
installed homemade silicone 'gasket' under power transformer
unfortunately I am lazy about controlled testing/evaluation.
But I can share this:
the 2x NOS vintage Sylvania tubes in PC-5 both tested VERY high on my B&K 747B tube tester so
I wanted them in PC-5 where they sound much better than my usual smooth-plate Telefunkens.
I am guessing that the silicone gasket under transformer may have enhanced quietness.
I have seen power-trans anti-vibration mounting & shielding in more expensive equipment.
Although I suspect multi-reasons I can now say that my PAS-3X is now much quieter in
phono mode----something I never achieved before.
I am very indebted to Pacific Audio Regenesis for his PC-6 analysis
and the helpful members of this fine forum.
setu
I imagine VTA preamps etc are much superior sound----but they are not really a PAS.
If I want really superior sound from my PAS-3X then I run the tapeout thru rear-mounted Noble 10K stereo log pot into ST70.
I had decided against installing such a pot into ST70.
I had replaced the sides and top with 1/8in mirror glass for mid-century appearance and EMI rejection.
So in April 2022 I went inside and did the following:
replaced all coupling caps with K40Y-9
installed late-50s Sylvania 12AX7A (7025) into PC-5 linestage
installed Raytheon/Balwin 12AX7 into PC-6 phonostage
removed all 120VAC outlets on rear
installed homemade silicone 'gasket' under power transformer
unfortunately I am lazy about controlled testing/evaluation.
But I can share this:
the 2x NOS vintage Sylvania tubes in PC-5 both tested VERY high on my B&K 747B tube tester so
I wanted them in PC-5 where they sound much better than my usual smooth-plate Telefunkens.
I am guessing that the silicone gasket under transformer may have enhanced quietness.
I have seen power-trans anti-vibration mounting & shielding in more expensive equipment.
Although I suspect multi-reasons I can now say that my PAS-3X is now much quieter in
phono mode----something I never achieved before.
I am very indebted to Pacific Audio Regenesis for his PC-6 analysis
and the helpful members of this fine forum.
setu