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

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assembled & tested, ready to plug & play

SP10 preamp

SP12 preamp

SP14 preamp

PH-14 phono

PH-16 phono


for KIT versions of these preamps, click here

here's an excellent unbiased review and discussion of a couple of our preamps . . . .

returns and refunds policy

SP10 preamp

a 4 tube line stage only preamp, 4 inputs, 1 output, remote control input and volume !!
Our newest preamp, a real bargain, better than any other tube preamp I've seen under $800 !!

new SP10 preamp, fully assembled & tested, $495 plus $30 shipping in USA

the new SP10 is an incredible bargain, there is no way I could have built this preamp for under $900 
so yes, I have to admit it's imported from China.  But before you turn away, I want you to know I have 
personally and throughly checked this out, it's now in my own personal system.
This preamp is extremely well built, solid heavy chassis, excellent circuit design, and great sound from four 12AX7 tubes.
The assembled/tested/warranteed version will cost you much less than I could build it for.
Included is a remote control for motorized volume (ALPs volume control) and relay selection of four inputs.
One output, no tape loop, no tone controls, just a super nice package that delivers excellent tube audio music.
I'm not selling a full kit, because that would cost much more than this fully assembled/tested unit.
But if you want to DIY, I can sell you an assembled PCB, power transformer, chassis, and volume control (manual or motorized)
but not the remote input selector, although there are dozens of those available if you want to look elsewhere.
Size is 12.5" wide x 12.5" deep x 4.0" tall and it weights a hefty 9#.

SP12 preamp

this is our most popular preamp, and probably the best value for your $$$.
Standard version in 12" or 16" chassis,

The SE upgrade is a popular option with the 16" chassis, includes 21 step master volume attenuator and dual mono gain/balance step attenuators,
instead of conventional volume and balance controls; We supply better quality ECC802 or mil-spec 6189W tubes

one of our customers posted this review on AudioAsylum here

SP12 preamp in 16" chassis
with conventional volume & balance controls, $1120 plus $40 shipping in USA.
SP12-SE preamp in 16" chassis
with triple attenuators
(21 step volume and dual gain/balance) $1120 plus $40 shipping in USA.
add the PH14 phono stage to the SP12
includes assembled PH14 phono and extra filament power transformer

SP14 preamp

this is our very best preamp, using larger 6SN7 octal tubes, in a larger 5" tall chassis.
Same circuit circuit design as our SP13 but on a much larger PCB, with NO room to add a phono section inside.
NOTE: For phono use with this preamp, you'll need to add a separate phono preamp such as our premium PH14 or PH16 phono preamp below.
This preamp has dual mono regulated power supplies for each channel, for both B+ and filaments.
STANDARD items include 21 step volume attenuator and dual mono gain/balance attenuators, iso-damping chassis, iso-mounts for the circuit board, and more.

Get more complete info here

SP14 preamp in 16" chassis 5" height
(21 step volume and dual gain/balance) $1450 plus $50 shipping in USA.

PH-14 premium phono preamp

This has a full power supply using tube rectification, with HV regulator and filament regulator.
This circuit has a 12AU7 tube buffered output for lower impedance, better drive capability, and enhanced and perfected RIAA EQ.
click here for more info and pricing

PH-16 premium phono preamp

This is our very best phono preamp, this is a phono only separate preamp, and INCLUDES premium grade resistors and capacitor.
premium grade phono only preamp using a JFET (10x less noise than a tube) as a current source in cascode with 6922 tube gain stage
for super low-noise cascode front end followed by passive RIAA EQ, followed by another 6922 gain stage, followed by an AIKIDO output buffer with two 6922 tubes.;
gain is 45db use with MM cartridges or medium to high output MC cartridges.

PH-16 phono preamp in 16" wide chassis
assembled, tested, ready to plug and play for $950 plus $40 shipping in USA

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