The Amp Garage

Yes try changing the bias point. The gain should rise sharply at some point and then level off.

dbharris wrote: ↑Sat May 11, 2024 2:50 pm New FET biased up easy. I set it for just under 3 for the Vdd/Vd ratio. It sounds good, but the volume is lower than the normal channel even with the FET trimmer wide open. I may bring the ratio closer to 2.5 and see if that helps.

What are the voltages at the top and bottom of the drain resistor?

Thanks Dai.

Moderators, maybe this thread should be moved to the new FAQ area?

To be fair, the Robben part of the video was a fraction of the overall time. He's talked about his Dumble amps and his introduction to and friendship with HAD many times before, but there always seems to be something new. I agree hearing different players and different guitars was really valuable, a...

If that is just heater glow you are seeing through the hole in the tube base I wouldn't worry about it. Are you seeing that through the gap between the index pin and the socket? Might the odor be transformer varnish?

I was trying to come up with a rationale, but in the end at 120V the current limit will be the same, Bulb Wattage/120

I usually plug the limiter into the Variac, but I'm not sure that it matters.

A Variac and a bulb limiter is the best arrangement.

The relay spec should be fine. More likely some wiring error, but you say “sometimes” cuts out, which sounds like a faulty switch or relay.

I worked on it some more last night but forgot to write the voltages down. From testing things earlier everything seemed ok, just a tad lower than what is on the layout and schematics since I had my variac running at ~115VAC to get the heaters right at 3.15VAC on both sides. I was thinking verify t...

What a great interview! Nice of them to zoom in on the SN stamp ;^), and this has to be the gold standard 102 sound sample.

Thanks for posting!

Pinned in D discussion section:
https://ampgarage.com/forum/viewtopic.p ... 89#p416389

I was about to say that to keep the 2nd gen's loading on the OD output, delete the 180k to ground and the 1Meg series resistor and go straight into a 250k pot for the added Ratio control. ...Should I pull the 180K and 1Meg resistor as the amp is now or is that for when it has been changed to the hy...

erwin_ve wrote: ↑Fri May 10, 2024 10:08 amStrange thing it happened to my mobile as well.

Same here.

Right now ampgarage.com is extremely slow/ not responding. I tried to answer some PM, after half an hour I gave up. This is showing up when answering a PM: That's the same error I was seeing when trying to view "New posts". Clearing the browser history fixed it. I just successfully sent and replied...