Tube el34

Contact Kevin at Upscale Audio, tell him what equipment you are using and your taste in reproduction(which varies widely, person to person) and he will hook you up. His matching, testing, and burning in procedures are second to none(as is his customer service). (http://www.upscaleaudio.com/bEL-346CA7-Typesb_c_86.html)

Let's see- You're comparing an amp that was introduced around 1960, and rated at 35WPC(actually more like 17WPC in reality) with one that came out in 1974, sporting 75WPC. Gee- I'm amazed that there was such a difference in their performance!! There have been numerous upgrades and mods offered for the ST-70. Many that truly improve it's output and presentation. It doesn't take much to bring one up to the level of performance of today's amps(of equiv. power). I enjoyed mine for quite a few years(performing my own mods), as the mid/high amp in a bi-amped system. BTW- The production of the ST-70 almost reached 300,000 units. A pretty popular amplifier it seems.