VTA SP6 Preamp

Roy Mottram's VTA SP6 Preamp

Completed on 1/16/08

PCB available at www.tubes4hifi.com

I guess I got the point where all the tweaking with power amps has been done and it's about time that I looked into preamps and speakers. So far, I have gone through several solid state preamps (NAD, Adcom, etc.). I also tried a passive preamp with a homebrew phono preamp. All these gave me performances a lot to be desired. I have always wanted to try a tube preamp or two, but I was somewhat put off by off-the-wall prices of preamps that were worth considering. I guess the Dynaco PAS-2/3 would have been an option that can be had for under 200 bucks, but some tweaking (PS upgrade, recapping, and tone control removal) would have to be done to make it listenable. I figured that if I were to spend more than $200 on a decent preamp, I might as well built something new. After having done some research, I narrowed it down to Aikido preamp or Roy Mottram VTA SP-6. I settled for the latter, mostly because I had to have a phono stage.

The harware (knobs and RCA inputs) on the chassis is salvaged from my passive preamp. Built on an oak base stained in dark cherry, and finished in high gloss polyurethane. I ended up using a 12x12 lexan polycarbonate as a top plate to showcase all the electronics and glowing tubes inside. The preamp uses 2 NOS RCA 12au7s for the linestage and 2 TAD 12ax7s for the phono stage. This probably is the best sounding preamp that I owned so far. It sounds very neutral and lets all the subtleties in recording pass without any coloration. It's fast, articulate and versatile. I would recommend it to anyone who's serious about their audion stuff.