sjs
Trade: SJS Electroacoustics
I had a couple of Tram 2 preamps about 10 years ago, which I reworked with Rod Coleman regs and a few other tweaks. One used 2A3 and the other used 45. The 2A3 was nice, the 45 was stunning. They use the dht as the gain valve in a Kimmel super mu circuit with a 6AS7 as the load.I came across this thread while doing a search and as a long time SET user it seemed interesting, though more so at the start than later.
My news is that the 2a3, or the 6.3v versions 6B4G and Soviet 6C4C, are not just output valves - they make stonkingly good line stages. I've just completed one for a guy who needs a low gain, low output impedance DHT line stage to feed a 10K input impedance amp. It sounds so addictively good - neutral, smooth, detailed, dynamic - that I'm building another one for myself as fast as possible. There are some 2a3 based preamps about, but driven by a 6SN7 which makes no sense to me - it's not needed or wanted. There was the Tram 2 2a3 preamp which gets a glowing review here. But it's a rare beast. It's not too difficult to build a 6B4G/6C4C line stage and it's a keeper for sure.
Diy HiFi Supply Tram Mk2 DHT OTL Preamplifier Take the direct route to the heart and soul of your music. Review By Clive Meakins
Diy HiFi Supply Tram Mk2 DHT OTL Preamplifier Take the direct route to the heart and soul of your music. Review By Clive Meakins - Enjoy the Music.com Review Magazinewww.enjoythemusic.com
I also had a 26 preamp which had a Lundahl step-down transformer on the output. That was a lovely thing.
How are you using the 2A3 in your pre, RC coupled, LC coupled or transformer coupled output?