Reverb question

[Tdale]

I'm looking at the schematic that's attached, and I'm trying to understand the reverb part.

This is how I read it.

The signal comes from the master volume.

Some of the signal goes through the 100K resistor to the PI tube.

Some of the signal goes through the reverb tube and spring reverb, then to the reverb pot, and back to the PI input.

The resistance in the reverb pot decides how much signal that goes through the 100K resistor and how much goes through the pot. If the pot has high resistance, the signal chooses the path through the 100K, and there is no reverb. If the reverb pot has little resistance, that's where the signal goes, and you get reverb..

Is this correct read?

I'm a little confused by the 2M pot and the 470K resistor.. Won't that make most of the signal go through the 100K resistor, and not through the reverb circuit, no matter how the reverb pot is set?

tommy

[Icetech]

You don't want alot of signal through the reverb, think of the reverb as its own little seperate amp.. signal splits.. some to reverb/some to PI... what goes through the reverb mixes back in at the pi (or whereever downstream) its not like using a seperate channel or anything.. just adding a little signal from the reverb back into the source:)

I think thats fairly correct, im not a pro though...
BTW.. i built that amp in that layout and totally love it...

[keithrick]

That is how I see it as well. There is a thread where Bob discusses increasing the 100K balance resistor to 220K w/ a 47pf cap in parallel. He stated that it made the reverb stronger. Other area's that have been discussed are the cathode caps. Do a search and you should find some interesting tuning discussions!

[Darkbluemurder]

That is how I see it as well. There is a thread where Bob discusses increasing the 100K balance resistor to 220K w/ a 47pf cap in parallel. He stated that it made the reverb stronger. Other area's that have been discussed are the cathode caps. Do a search and you should find some interesting tuning discussions!

I have not yet experimented with the balance resistor but I believe either in the Funk Workbook or in the Torres book it says that if you were to decrease the 3M3 resistor in a Fender Reverb amp you would increase gain and at the same time decrease the reverb. So this makes absolutely sense.