I bought my first ST-70 about ten years ago on evilauctionsite. I was hot to do the Van Alstine mod. I'd known about him for 30 years and had always wanted to try one out. It was a nice amp but cost like $1250+ even back then, once you buy the chassis and send it to him to do the mod.
Some years later I came to feel that my solid state system (Dynaco ST-400 with early Van Alstine mod) had better tonal balance than my tube rig. I played around quite a bit with equipment and speaker shuffling and was ready to blame it on my tube preamp - a lovely Van Alstine Super PAS 3 with his black face plate - when I happened onto and rebuilt a Dynaco ST-35. I realized then that the Van Alstine Ultimate-70 sounded like a lumbering aurochs, while the ST-35 (rebuilt boards and the Dave Gillespie EFB mod) sounded like a light and airy sprite with the same mids and a high range that was new to me.
I sold the amp. Later I read Gillespie's excellent long form analysis on baselining the ST-70 over on that other forum, and I realized that I had never established a baseline for the stock ST-70 before I sent it off to be expensively modified.
Cut to a few weeks ago, I ran across a local posting for an ST-70 that was pretty much stock, but had been serviced recently. It had new tubes and may have had some other work done, but I wasn't sure.
I bought it and spent a couple of days listening to it, to try to establish the old baseline. I found that it sounded terrible - muted, shrouded, a boxy soundstage. But the point was to live with the original design for a while and get to know it better then do the VTA mainboard and associated upgrades. Driver boards, input and output connectors...
So I'm looking for hints and suggestions as to how to get the most of this opportunity. Pics to follow - it's a factory wired unit with those two-hole security screws on the lower chassis cover so I haven't gotten into the unit yet... But I want to start bouncing ideas around.
Some years later I came to feel that my solid state system (Dynaco ST-400 with early Van Alstine mod) had better tonal balance than my tube rig. I played around quite a bit with equipment and speaker shuffling and was ready to blame it on my tube preamp - a lovely Van Alstine Super PAS 3 with his black face plate - when I happened onto and rebuilt a Dynaco ST-35. I realized then that the Van Alstine Ultimate-70 sounded like a lumbering aurochs, while the ST-35 (rebuilt boards and the Dave Gillespie EFB mod) sounded like a light and airy sprite with the same mids and a high range that was new to me.
I sold the amp. Later I read Gillespie's excellent long form analysis on baselining the ST-70 over on that other forum, and I realized that I had never established a baseline for the stock ST-70 before I sent it off to be expensively modified.
Cut to a few weeks ago, I ran across a local posting for an ST-70 that was pretty much stock, but had been serviced recently. It had new tubes and may have had some other work done, but I wasn't sure.
I bought it and spent a couple of days listening to it, to try to establish the old baseline. I found that it sounded terrible - muted, shrouded, a boxy soundstage. But the point was to live with the original design for a while and get to know it better then do the VTA mainboard and associated upgrades. Driver boards, input and output connectors...
So I'm looking for hints and suggestions as to how to get the most of this opportunity. Pics to follow - it's a factory wired unit with those two-hole security screws on the lower chassis cover so I haven't gotten into the unit yet... But I want to start bouncing ideas around.