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 !!
A real bargain, better than many I've seen over $800 !!

new SP10 preamp, fully assembled & tested, $520 plus $30 shipping in USA

3-4 weeks delivery

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.
This 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.
Size is 12.5" wide x 12.5" deep x 4.0" tall and it weights a hefty 9#.

SP12 preamp

a 4 tube line stage only preamp, plus tube power supply,
fully assembled/tested/ready to play preamp in 16" wide chassis
The SP12 now includes as STANDARD premium resistors and capacitors.
The SP12 preamp includes a 21 step volume attenuator and dual mono gain/balance 21 step attenuators,
instead of conventional volume and balance controls; We supply better quality 12AU7 or mil-spec 6189W tubes.

SP12 preamp in 16" chassis
with triple attenuators
(21 step volume and dual gain/balance) $1100 plus $40 shipping in USA.

email me to order an assembled preamp, 3-4 weeks delivery

add the PH14 phono stage to the SP12
includes assembled PH14 phono and extra filament power transformer

one of our customers posted this SP12 review on AudioAsylum here

SP12 preamp in SP10 chassis including remote control
$750 plus $40 shipping

email me to order an assembled preamp, 3-4 weeks delivery


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 SP12 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

PH-14 premium phono preamp

This has a full power supply using tube rectification, with HV regulator and filament regulator.
This circuit has a 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 44db 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 $990 plus $40 shipping in USA

email me to order an assembled preamp, 3-4 weeks delivery


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