Is a 50v Presence cap too small for 100 watt amp

[talbany]

I agree Tony, very difficult to trace when you can’t see where wires are going. I judge these things based on the angle the wire makes at the socket/terminal strip, bend radius and what would seem logical to me. So my best guess is the rca socket (from tank) goed to v3a. V3a out goes to reverb return pot, return pot middle lug goes to v3b with the 10meg resistor. V3b out goes to the relay board. At least, that is what I can tell from the couple of pictures I have seen.

Cool!
Revised version would then be
1.V2A..Reverb input amplifier/ Send pot
2.V2B..Tank driver
3.V3A..Reverb return amplifier/ return pot
4.V3B.. Mixing amplifier

Mixing is done at the MV connection on the relay board w/270k mixing resistor. Makes sense!

Lets see if this is correct?

Tony

[Guy77]

Hi guys here we go!!
Just to clarify , when I say v3b I mean the side of the tube closest to the Power section and v3a is closest to the first Preamp tube V1.

V3a grid actually connects to the RCA out Jack.
V3b grid goes to the Reverb return Wiper.
The V3a plate goes to Reverb return input.

V2a plate hits the input of Reverb Send pot

The v3B plate goes to Input of the Master Volume via the relay board, they seem to connected to the same pin on the relay board. The v3b plate wire connects to the blue cap on board with resistor after it as seen in my first post pics (.002uf)and then to the top of relay and then Master Vol wiper via a wire at the bottom of relay at what appears to be the same spot!

Guy

[rootz]

thanks Guy. Let me see if I get this correctly: clean out and reverb out are tied together at the input of the od relay (so pre od reverb) or do you mean that reverb wet is mixed in after the relay at the master volume? That would mean the possibility of clean wet signal over OD signal.

[Guy77]

thanks Guy. Let me see if I get this correctly: clean out and reverb out are tied together at the input of the od relay (so pre od reverb) or do you mean that reverb wet is mixed in after the relay at the master volume? That would mean the possibility of clean wet signal over OD signal.

Hi Rootz. I am going to draw out the OD relay with all the connections to it and post it here in a few minutes. Hopefully this will better answer your question. Thanks!

[Guy77]

I attached a pic listing all the relay connections. The solder points on the drawing are positioned exactly as they are on the relay.

Also my very last pic attached here shows effects loop Grey wire entering the phase inverter.
Hope this helps! We can do this.

Edit made a mistake on relay wiring for Master Vol. Will fix now!



Amp is on my bench ask me any questions guys!
G.

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Connections on reverb tack jacks.

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Effects Loop feeding Phase Inverter with Gray wire

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[Guy77]

Guys this is corrected OD Relay board connections! Its updated as well in my previous post.
Tone stack cap correct values are actually

Tone stack out cap is .01uf
Treble cap is .001uf
Mid cap is .047uf
Bass is .1uf

Mid boost switch cap is 330pf

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[rootz]

Yes! First additional question: how’s the other relay board wired? The PAB relay I mean.

So the tone stack is much more Fender: less mids because the treble cap is smaller. Would that account for the good cleans?

[rootz]

Cap size over the 220k resistor on the rca connector would be another thing I’d like to know.

[rootz]

Can you confirm all reverb related triodes are connected to the same PSU node? So all connecting to the 27k power resistor on the PSU board?

[Guy77]

Can you confirm all reverb related triodes are connected to the same PSU node? So all connecting to the 27k power resistor on the PSU board?

Hi Rootz! i will answer all your questions in the next hour during my lunch break

[Guy77]

Cap size over the 220k resistor on the rca connector would be another thing I’d like to know.

The cap on the 220k resistor on rca connector reads BC 222 so I imagine this is a Visay 222pf cap

EDIT: Thanks for the correction Tom ! I should have looked up the 3 digit code before posting! Yes 2n2

All v3 and v2 reverb triodes come from same power supply node as you mentioned.

I will get you the other info later today!

Thanks Rootz

[Guy77]

Yes! First additional question: how’s the other relay board wired? The PAB relay I mean.

So the tone stack is much more Fender: less mids because the treble cap is smaller. Would that account for the good cleans?

Yes I believe this help account for the great cleans. I also adjusted the v1 voltages from 176v to 200v and the client liked the cleans even more. They were even fuller at that voltage!

This amp is running Pacific brand made in USA Transformers for all transformers

Guy

[mojotom]

Cap size over the 220k resistor on the rca connector would be another thing I’d like to know.

The cap on the 220k resistor on rca connector reads BC 222 so I imagine this is a Visay 222pf cap

I would say 2n2 for 222 and that’s a common value at that node.

[talbany]

So the tone stack is basically a low plate "Classic" w/ Mid boost. I've seen this on other 2 Rocks as well. You can confirm this if it has a 100k mid pot. Everything else looks proto-typical Dumble.
BTW?.. Notice the treble cap (mounted on the mid switch) is an old ceramic and not a mica
I imagine this amp has a Master vol cap. That would be critical as well as the composition.

Thanks Guy for getting back. That pretty much answers my questions. Looking forward to getting the schematic

Tony

[Guy77]

Hi Tony. yes Mid pot is 100k and bass pot is 250K I imagine Treble pot is 250K.
Cap (ceramic) on Mid boost has 331 written on it and bright cap (ceramic) has 180 written on it.
No cap on the Master volume pot or the Effects loop.

Both OD pots are 100K and OD trimmer is 100K .

V3B plate cap is.002uf
V3A plate cap is .001uf
V2B plate cap is .002uf

Will check PAD boost tonight.

Cheers
Guy