From what I understand, the Princeton Reverbs of the blackface/silverface era are odd ducks in terms of circuitry compared to the other models of the same era that are supported on the Fender PCB here. Are there any plans to produce a PCB for Princeton Reverb circuits down the line? Or, is there a way to make the Fender style PCB accommodate a Princeton Reverb? I am guessing not, but thought I would at least pose the question.
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Also, regarding proper dress issues, there are some who feel that V2 pins 1 and 6 should be connected via a connecting wire that lays flat on the chassis and loops around the back of the tube socket, not a straight jumper across the tube socket. If you take a look at the Fender (PR AA1164) created layout you can see what I'm referring to.
I just noticed something that might need some attention. The PR didn't have a choke. Instead, originally it used a 1K 2W CC resistor that served as a choke. These would typically fail over time and need to be replaced, so it's nice to see a 3W resistor suggested here. However, a better choice might be a wirewound type 5W resistor that (because of the wire coil inside it) might offer a slight choke affect as well as a longer life. Antique Radio Supply/cedist.com offers a cylindrical version of said, but also the ceramic block type exists as well, both 5W.
At this point, after the 1K 2W CC resistor (listed as 1W on the Fender Schematic) that Fender used (in their original design), Fender ran plain wire to the #4 pins of the 6V6s. Basically this 1K resistor replaced what Fender would typically accomplish with a 100 ohm choke and two 470 ohm 2W resistors in their more expensive amps, one being attached to either 6V6. So here, this PCB includes a place for the two 470 resistors that Fender didn't use in the original build. And this is something to consider. If you add the two resistors (along with the 1K resistor in the power supply), this will cause slightly less output from the amp and also a bit more 'compression'. This may or may not be what you want, so give the amp a listen when you get it completed. The other option, if you are looking for more headroom, beyond using just the 1K resistor, you could actually use a 100 ohm choke (as is found in a Deluxe Reverb, for example) and then add two 470 ohm resistors to pin #4 of the two 6V6s. Actually, this is probably what I will do, FWIW.
Have two headed my way, looks like the end of the month. Have two chassis’s ready and am grabbing parts in the meantime.
Waiting for mine to arrive right now, I have faith that it will be a quiet build using this PC board layout. Should be fun to build, too.
Agree, a Princeton Reverb would be very nice (with a 12” speaker).