Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => PC Express and JSchem - Schematics and Layout diagrams => Topic started by: tubenit on November 13, 2006, 05:33:38 pm

Title: Original Princeton Reverb schematic
Post by: tubenit on November 13, 2006, 05:33:38 pm

Check for errors. This is intended to reflect an original PR schematic. Should note that there were different versions of Princeton Reverbs.  You can mod this schematic to match yours.

I've add a couple more schematics that you can edit.  One is a PR using some Deluxe Reverb PT & OT without vibrato  & the other is the same thing but with a dual ganged  PPMIV

Tubenit

 ALL these links should work now.     

However, if not  .............. You can find most of these schematic in the "Broken Links" file.  Write down the name of what you are looking for and then click on to this Broken Links file list.  Some of the files on this thread may open and some may not. Use the list on the "Broken Links file" to hopefully find what you are looking for:

http://el34world.com/Forum/index.php?topic=17420.0 (http://el34world.com/Forum/index.php?topic=17420.0)

Title: PR layout board
Post by: tubenit on November 13, 2006, 05:34:32 pm

This is intended to reflect an original PR schematic in a layout using paralleled terminal strips or turrets.

Check for errors!

Tubenit

Title: Re: Original Princeton Reverb schematic
Post by: tubenit on April 06, 2007, 09:15:35 am

PR-jazz  schematic


I have NOT built this. Look for errors.   Someone on the forum was asking about a good practice jazz amp and there was some debate between the Princeton (non-reverb) and PR.

I drew this up but have not built it.

With respect, Tubenit

EDIT  2/18/2018     I've added a Princeton Reverb with "one tube reverb" & no vibrato

Title: Re: Original Princeton Reverb schematic
Post by: jjasilli on February 24, 2009, 09:45:12 pm

This is Version 3 of my Mods. Finally got around to improving on the last set of mods to this amp:

1.  Tremolo Intensity Fix.  Moving from 6V6's > to 6L6's essentially means doubling the bias volatge, which leaves the stock tremolo anemic.  This was addressed by halving the value of the 1M attenuating rsistor on the way to the Intensity pot.  While i was in there. . .

2.  A bias sense resistor was added with test pin jacks on the rear panel.

3.  A RAW control was added, with pot on the rear panel.  I put a chicken head knob on the pot, so hopelfully I can feel its rotation in use from the front of the amp. 

All works well.  That's it for now.  Maybe in the future:  SE mod; pentode triode SW; cathode bias SW.  Too many amps; so little time.

This amp has a really great vintage Fender BF tone.  The RAW contol contributes to a Tweed-like overdrive tone.  I was hoping for something more Marshally, but I guess there's just not enough gain stages.  RAW describes it pretty well!  A really ballsy combination is to bi-amp it with a Traynor Bassmate, by jumpering the input jacks.