Will Vincent "Dynaco" Amps

I have one of Will's Dynaco ST-70 rebuilds. I have found it to be a very good amp. It has a nice smooth sound. It also very good bass for a lower powered tube amp. Though the sound was good the way it came, i couldn't help but roll some tubes. I ended up with winged "C" el-34's, RCA 7199's and a Mullard gz-34. With these tubes i feel the amp jumps up another level or two. The tube that made the biggest difference was the gz-34. They aren't cheap, but the improvement it made to the overall sound is well worth it.

I have one of Will's st 70 amps and it is a piece of art.

The amp sounded nice with the el34 tubes in it, but I also wanted to try some tube rolling..... and after a matched quad of gold lion kt66 re issues, this amp has unreal depth, imaging, and much better detail than before.

Now I need a real pair of speakers... I currently have quad 11L mini monitors.

It does not hurt that I am using a classe audio dr6 preamp, but even after adding the pre the magic was not there until I added the kt 66 tubes.

As an added benefit from the kt 66's , they run MUCH cooler than the el 34's and were easy to bias since Will puts in an extended range very high quality bias pots in his amps.

I've got a pair of Will's Dynaco mk iiis; beautiful aesthetics and sonics. Just one word on the looks: WAF was off the scale (glowing tubes!), and everyone who comes in the living room makes a beeline for them.

Dav65mus,
I was not aware i could use kt66 tubes in this amp. I know i can use kt77's. I will have to look into this. By the way the amp is a work of art. My girlfriend thought it was a bomb when i openend the box, but i think it looked great.

Tommy

I found some threads dedicated to st70 upgrades and one of the mods was using the kt66 gold lion re issue tubes.

Before I ordered a matched quad, I called Will to make sure they would work properly with the amp and he said yes.

In Will's reworked st70's you can use el34, kt77, kt66, and I think he said 6L6 also. He uses upgraded bias pots that have a wider range than the original's and all you have to do is adjust the bias to 1.5 - 1.55 volts on your new tubes. (The kt66 tubes required the bias to be adjusted down compared to the el34 since they use less current than an el34)

The soundstage width, depth, "holographic" imaging and high end detail all improved so much with the kt66 tubes, I could not believe it was the same amp!

The gold lion re issue's don't come cheap, but I am very happy I put a set in.

Good luck and enjoy your new amp.