AB for M125?

Both amps are converted and operating well. Definitely not missing those manual trim pots! Once I switched to attaching wires to the top of the board the installation process became a lot easier.

I read about some of the early issues with these boards but the new Ver 2 clearly addresses those.

Interesting what you find when you open up your amps after a couple years. In my case a noticeably domed cap and a couple burnt resistors. Besides the upgrade it was definitely time for a tune up!

Well with a couple weeks under the belt I can state that I am really liking these AB boards. The daily tedium of bias checking and adjustment is quickly fading into a bad memory. Unlike BAB (Before AB) the bias is always dead on now, and I mean dead on. Each day reading across tubes is exactly the same as previous day, within 0.001 V, incredible. Installing them was well worth the effort. There is an adjacent benefit as well in more consistent sound quality.

Knock on wood - 10 years w/M125s - no bias issues.

costerdock wrote:Knock on wood - 10 years w/M125s - no bias issues.

Nice track record. You must have been at the front on the line when these came out?

LeGrace wrote:Well with a couple weeks under the belt I can state that I am really liking these AB boards. The daily tedium of bias checking and adjustment is quickly fading into a bad memory. Unlike BAB (Before AB) the bias is always dead on now, and I mean dead on. Each day reading across tubes is exactly the same as previous day, within 0.001 V, incredible. Installing them was well worth the effort. There is an adjacent benefit as well in more consistent sound quality.

After all the sturm and drang of yesteryear, it's encouraging to see LeGace having such success and dominion over the restrained electron.

Nothing worse then an unrestrained electron! It is nice just flipping them on now and no longer worrying what the bias is doing.