Most Quiet TUBE Preamp. Linestage. $ 12K or less

I'll bet it sounds like a killer preamp Peter. Best Wishes on your audio adventure as a manufacturer. If you ever have any photos to post, I'd love to see it. What kind of tubes are you using? Line stage or w/ phono? Are you still modifying Counterpoint gear?

I am using high efficiency speakers (97db) and want tubes so the noise issue has been very important to me. I have used a number of linestages over the years and by far the best sounding AND quietest is my current Herron VTSP-3AR02. The Herron embodies an uncanny ability to preserve the musical flow, is easy to operate with a number of useful features and is absolutely dead quiet. It also has the ability to adjust output (essential in my view) so that folks like me with speakers that super efficient can dial down the output to bring the noise floor down even further.

J,

Yeah still modifying Counterpoint gear, about two units are
sent to me each week. I am able to rebuild the old amps
without the high price of the new boards. I will probably
advertise modifications for the preamps soon, that take them
to a different level for half the cost or less than Counterpoint
was charging. My partner can repair any audio component,
TTs, DACs, etc.

I am using the old 226 tube (you can sub in the 101D),
5AR4, 3A5, 12AT7 and 0A2. The 226 and 3A5 are DHT, the
unit is transformer coupled (we wind our own) so no
capacitors in the signal path, TVC volume control, and tube
regulation to quiet the unit down. I was using filter chokes
and capacitors but like Dodgealum mentions above, I tried
the preamp on high efficiency speakers 99db and we heard
some noise so we switched to the tube regulation design.
The noise level now is .001 on our meter. The only two
options left to improve the sound would be copper chassis
and maybe a custom transformer form Plitron. I have to work
on a website soon and shipping box. We received our first
two orders this week for the preamp, phono preamp and TT
that we design. The turntable is an old Lenco that we modify.

Next we are going to built tube amps designed after the old
Marantz 9s. I do like the EL34 tube sound.

Happy Listening.