Tube amp comparison


Hello,
I would like some feedback (sound quality, issues etc.) on three optional tube amps. They are:
1. Dynaco ST-70 with Dynamutt triode setup
2. Marantz 8
3. McIntosh MC225
Thanks.
128x128steelyjoe
I own a Dynaco ST-70, I have owned a McIntosh MC 30 and I have heard the Marantz 8b. The marantz sounded the best to me. The Dynaco was the cheapest of the 3 but still sounds decent. shay
Marantz 8 (8B)best overall, Mc225 well rounded and neutral for then, at about 25 watts. The Dynaco at 15 watts or so in triode(30wpc normal) doesn't sound that good in triode wired mode IMO. The ST-70 is best for its midrange, when run in it full output(pentode) designed mode. Most pentodes usually don't sound any good when rewired to triode. They(ST-70) were designed for pentode operation. The ST-70 has better mids (tossup with the 8B) than the Mac, but tubby bass, and laid back highs. The EL34 Marantz and Dynaco have a lot of tubes to choose from,for rolling. The Mac sounds best with NOS Westinghouse, and good with other Nos 7591s.I havn't heard one with the new 7591 tubes.
Let me add, any of these can sound totally different if they had new coupling caps, or mods done.
Agree with above and favor the 8b. I bought one for nostalgia to go with my 10b and 7c. I wasn't expecting much but got a real pleasant surprise using it to drive some Sonus Faber Guarneris. I like being able to roll the el34's and bias each one individually.
Heard Will Vincent's Dyna 70 triode mod (22WPC) recently at a friend's house. Sounded fabulous.
It would be hard to compare those totally different(Dynaco named) amps to a Stereo 70. There is one for sale now that has different output transformers on it. Definitely not a Stereo 70 tranny. The others that are painted would be hard or impossible to tell what time frame they were from, as the company went through several different changes on in house made parts, to having them made for them outputs, and other parts. They look nice, and may sound nice, but everyone may have a different version. The one that's for sale now(with those outputs) could never be made to sound like the original.Nice looking though.
Own Dynaco St70, Dynaco Mark III pair with Poseidon driver boards and a Marantz 8B. The only McIntosh I have had any experience with was a ss 2105.

The Marantz 8b is on my "A" system, and the Dynas are on my office system.

8b is my choice.

Thanks, Bruce