**I second PA's suggestions. The 7025 (if you can find them) were specifically designed to be quieter than regular 12AX7 valves. Telefunkens will likely cost a small fortune.
**Looks cheap to me. I purchased a couple of Dynaco PAS3 kits back in the 1970s (around $120.00 each). I built one and used it for a few years. The other got packed away. I uncovered it a couple of years back and sold the unassembled kit for $1,200.00. The new owner was thrilled (he was a medical student in the 1970s and could not afford one then), given it used Telefunken 12UA7 valves. He had valued the valves at $400.00 on their own. Dunno about 12AX7s, but I've seen other Telefunkens sell for a large chunk of money. That said, I agree with your original suggestion to use 7025s. I built a preamp in the late
1960s using 12AX7s and then swapped them for 7025s. Far quieter.
**It's been awhile since I worked on musician amps. I didn't realise that they'd moved to DC filaments. It's been common on hi fi amps for quite some time, as I'm sure you already know, and, of course, my dearly departed 1960s Hitachi clone of a Tektronix 545A (500 Watts power consumption), which used a bunch of 6080 twin triodes for filament regulation. All the vertical valves' filaments were operated in series. Great CRo to use during the Winter. Not so nice during Summer.
**Dunno. I got a bunch of nifty old valves, including some GE MOV KT88s. I'll whack 'em on eBay soon and find out. Back when I used to fix Wasp amps, I used to pay 25 Bucks for a KT88. Wish I'd stacked a bunch away. Geez, I haven't seen Ron Holden for 20 years. Last time I spoke with him, he was an Amway reseller. Shame. Talented guy. I did sell some stuff to Gil McPherson about 6 years ago. Another good designer of musos amps.
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