Here is the comment from Winston:
I had never soldered a pc board before this kit and was amazed at how quickly I figured the technique out. The best part of all is that the preamp sounds great. I have it connected to a Hafler power amp and a pair of Magnepans. All of my friends are impressed by the sound and cannot believe that I built a tube preamp kit from parts. This video is my proof.
Extracted from http://cheaptubeaudio.blogspot.com/search?q=tu-875
Building the preamp was a more cumbersome effort than any of the amps. The small preamp incredibly houses a full-function MM/MC phono section (switched by a button in the back) and the densely populated circuit board took quite some work. Special care also had to be taken in soldering the closely spaced pins of the IC chip (for the MC phono), so this kit may not be for the first-time kit-builder.
Ergonomics for such a compact unit is exceptional. The volume knob to the right has a smooth feel. A gentle push on the left balance knob neatly selects inputs.
Sonically, this preamp is truly exceptional. Its vanishingly low background noise shall shame many a (much) costlier preamp. It is hard to say whether the line section or the phono section is the more brilliant one. The line section uses only 1x 12AU7 and its sound is neutral, smoothly detailed and surprisingly sophisticated. Violin replay is top class: equally revealing of the string and the body; and managing to sound harmonically rich yet never etched. It is only in music of the greatest dynamics (such as well recorded orchestral music or piano) that the preamp restrains itself and sounds slightly flat in comparison with much higher-cost units with big power supplies. Nonetheless, what this tiny power supply section can do is still mind-boggling. I have partnered this preamp with amps from Verdier, Wavac, even Kondo, and it never bats an eye, such is its confidence.
The quiet phono section uses solid state for its MC section and 2x 12AU7 for the MM section. I have previously written something on it in a "group test" (click here). The tubed MM section is superior to many outboard phonoamps and compares favorably with classic tubed units, though you should not quite expect the performance of top-class units like those from ARC and MFA, for example. What is just as surprising is that the MC section, which has excellent gain (it can even manage my Ortofon MC-5000), manages to sound quite tactile and even handed, without the rather sterile cardboard quality of lesser outboard phonoamps. Taken into overall consideration, it is hard to think of any outboard phono units up to several times its cost that is as even a performer as this unit.
Vacuum Tubes :12AU7/ ECC82 x 3
FET (for Phono) 2S170 x 4
Input terminal PHONO (MM/MC: is changed by rear panel switch)
TAPE(MD) x 1
Output terminal PRE-OUTx1
Input resistance PHONO:100 ohm (MC) /50 k ohm (MM)
Maximum power: 1kHz、THD2%）
REC-OUT( PHONO ):13V
SN Ratio (IEC) PHPNO: 84.5dB (MC)/72.5dB (MM)
Frequency PHONO: RIAA 0.8dB
Power source DC7V +/- 0.5V consumption currency approx. 1.8A
Original stabilization AC adapter ( input