The Amp Garage

As recommended above, 220k into 100k trimmer with a 4k7 tail to ground is what I have in my 124-ish amp. It's set around 25k to ground, and it works very well. Those values (except the tail resistor) are common to 102 and 183 as well. I’ve changed the trim pot with a brand new 100k, as you advice m...

What is best OD trimmer value?

I haven't an OD trim installed on rear panel but only 250K trim installed on board after 220k entrance resistor. I can try to remove 250k trim from the board

This eveninig I try to change v1 tubes

Here the voltage chart.
Trannies are classic tone twin set
PT secondary wired for delivery 345-0-345

Wonderful, I hope they ship fast

Now 220K on 250 trim
previously (attachment) 220K on 100K

martin manning wrote: ↑Wed Mar 28, 2018 3:38 pm

dariez75 wrote: ↑Wed Mar 28, 2018 3:09 pm Sorry for bad explanation, what I want to say is that my amp sounds good but when this one is on clean channel the master seems too low despite when od is engaged.

I think your OD entrance trimmer is set much too high.

But if I set the 250K OD trim halfway, I have too low drive sound

Thank guys, when I'm home I fill the tab.

Sorry for bad explanation, what I want to say is that my amp sounds good but when this one is on clean channel the master seems too low despite when od is engaged.

thanks modman but I was searching the 2nd generatio chassis, the same used in first pictures of the thread

Where I can buy this kind and others dumble chassis?

Hi guys, I've recently finishend a #124 ODS using files you shared here, the amp sounds fantastic, as I ever desired. Unfortunaly I hear a big difference in volume between clean and OD channel. Could this be normal with low-plate design or maybe I did some mistake? Fort instance, when I play the cle...

The oldest 25W resistor had a strange behavior, it doesn't drop voltage in constant way but in "sinusoidal way". Using a multimeter we seen the drop voltage was inconstant. For instance, before resistor I've got 377 Volt, after the resistor 376 thus 340, thus 250 until to 20 volt. I wasn't able to p...

Thanks