Schematic for your feedback

[rutledj]

Well. take another look and see if I have it correct now.

[dogears]

Tons of errors....

Well. take another look and see if I have it correct now.

[rutledj]

Thanks but that doesn't help much

[dogears]

That is why I sent a PM simultaneously.... You did not check your inbox! LOL

Thanks but that doesn't help much

[rutledj]

OK. Here is the latest complete circuit.

[simsamp]

hello there,this is my first post...,so here goes...
i was looking at your schematic and noticed that
you opted for a .022uf coupler after v1-b...
i think every schematic i've looked at showed a 047 there,i was wondering what that would do for the sound if the amp....

________
VOLCANO VAPORIZERS

[Tonegeek]

Rut

only need one 47p at most across the PI plates, not to the cathodes.
PAB still not right. It should lift the bottom of treble pot and lift the wiper of the the bass pot when engaged
Not sure about the presence wiring. looks like a Marshall PI in which case The 4.7k resistor should go to ground and the cap and pot (wired as variable resistor) are in series across the 4.7k resistor.

The 47p on the clean master could shunt some highs when in OD. ODS 101 should show a way to deal with that.

[rutledj]

Hopefully I'm closer.

simsamp: I'll probably end up playing with those values but I would suspect less bass with the .022

[fabiomayo]

Looks like dogears made you busy, rut.

The coupling caps from PI to power tubes is right? Other schems show a .1uF instead of the .02uF you have there.

Hope you project comes out alright.

[dogears]

The caps are .02 in this style circuit....

Also, the treble pot can be either audio or linear, but I prefer linear. Most if not all Dumbles are linear too....

The coupling caps from PI to power tubes is right? Other schems show a .1uF instead of the .02uF you have there.

Hope you project comes out alright.

[heisthl]

The 15K bias tail resistor will never work - should be more like 51K. Ditto on the above recomendation on the presence network connections - get the 4.7k direct to ground and put the cap and pot in series to make one leg in parallel with the 4.7k. You will also need to adress the crappy non-HRM tone you will get with the HRM input trim values not to mention the volume change when you switch out the HRM tone stack, you may need some R value to ground to compensate. Glasman does this HRM and non-HRM sucessfully somehow in the same amp but his methods are probably proprietary(as they should be).

[heisthl]

On second thought the 15K might work if you use EL34s in the output but then you would need to up the sceen resistors to 1K (I would do that anyway).

[dogears]

Oops...did not notice the switchable HRM. Can't do it! Scrap it. Won't work without MAJOR MAJOR revisions. Trust me.

[Bob-I]

...I'll probably end up playing with those values but I would suspect less bass with the .022

Start with known good values. Don't screw around blind, there's a reason for everything in these amps.

[rutledj]

OK. Not sure if I have the Presence correct yet or not. Seems like a lot of these suggestions don't match the posted schematics but I guess they are workable "tweaks"?

I'll go Non-hrm for now and try to figure out the switching later after I have something that works.

Bob-I: The .022 in the Clean 1 ckt came from a schematic that I think you posted a good while back so I'm hoping it is correct. Can you comment on whether this ckt came out ok?

Thanks to all for your feedback.

Rut