tubes 4 hifi
 "the path of least resistance is through a vacuum"

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introducing the super performance SP20 preamplifier

March 2023 - I am excited to present my newest preamp, the SP20.

This new preamp is based on the CAT SL1 preamp, limited production over the past 30 years and very highly rated.
30 years ago this preamp was around $6000 and is now around $30,000. So the SP20 is not an inexpensive preamp.
It's designed for those who love to roll tubes and capacitors to fine tune the sound quality.
The SP20 uses the same circuit design, using four tubes, a 12AU7 for the input gain, followed by two 12AX7 tubes, with a 6922 tube output driver.
I have two versions available for sale. The SP20-B is the simple version, the SP20-E is the higher end version.
The main difference is the power supplies. The SP20-B has two filament regulators, and one B+ regulator.
The SP20-E has three filament regulators, and SIX B+ regulators, truer to the original design.

Let's get to a description of what makes this a great sounding product.
With three different tubes in four positions, this preamp gives you the best of tube sound.
You can choose your favorite tube brand for each tube. With all the voltage regulators, you get the cleanest, quietiest, most transparent sound possible.
There are also 3 coupling capacitors in each channel, so you can use your favorite capacitors to fine tune the sound further.

send email to DAN at: to ask questions or special order a preamp.

I currently have one of each type built and ready to ship . . .
1 - the SP20-B with an LCD display, with remote control of input and volume
2 - the SP20-E with dual mono stepped attenuators and 5 toggle switches for functions, similar to the original CAT SL1 preamp.

SP20-B complete preamp assembled/tested as shown $950, with tubes
SP20-B preamp assembled/tested with NO tubes $790
SP20-B circuit board only assembled/tested as shown $160

SP20-E assembled/tested preamp as shown $1150 WITH tubes

SP20-E assembled/tested circuit board ONLY NO tubes $260 (the parts and PCB actually cost $400)

SP20-E assembled/tested preamp as shown $990 NO tubes

Buyers note - this preamp does NOT have a phono preamp section in it - it will NOT fit inside this chassis!

inquire about any other options or modifications you might want via email . . . .

send email to DAN at:

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 tubes 4 hifi
 "the path of least resistance is through a vacuum"