Princeton reverb build in a trainwreck chassis

[norburybrook]

Hello,

My first post over on this Fender forum.

I've started a Princeton reverb build in an old Wreck chassis i had laying around. I've managed just about to get it all in but not in the usual places everything is reversed and the transformer mouinting is a little unusual for a fender.

Had to do lots of drilling and cutting but here's where i got to today. I realsie I've got to take the OT off tomorrow to mount the stand offs for the bias board.....doh!! Aslo the lovely fender knobs i bought don't fit as the pots are slightly closer together......

Mike at modulus amps made some great plates for me and did reverse turret boards. He's a top guy

IMG_20190618_165013-01.jpeg

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To be continued.

M

[Stevem]

It's looking darn good!
Will this build end up as just a head, or a combo amp?

If is just due to be a Head your going to need the cabinet tall enough to get the reverb pan atleast 6 inches away from the top of the power transformer height wise and the output side of the pan will need to be on the other side of the amp from the power transformer if you don't want a large amount of AC 60hz to be present when you turn up the reverb.

[sluckey]

Sunn preferred a 1/2" space between PT and tank...

[norburybrook]

Sunn preferred a 1/2" space between PT and tank...

LOL that's tight.


No this is going to be a grab and go combo, i don't actually own a grab and go combo. Everything is Heads and cabs. I have a vintage ,USA acusonics reverb tank ready for action that's been waiting for this build.

I'm going to build the cabinet approximately to size but not worry too much, maybe go a little larger and put a 12 inch speaker in there.

Any suggestions for a good 12 inch for this.



M

[10thTx]

Emminence Texas Heat or Emminence Cannabis Rex (if needing to smooth highs) might be reasonable choices for a PR. (Warehouse ET65 might be another?) Depends on how Fendery you want it to sound? IF you want it real clean and Fendery then the Weber 12F125 is a reasonable choice to consider, IMO.

With respect, 10thtx

[norburybrook]

Emminence Texas Heat or Emminence Cannabis Rex (if needing to smooth highs) might be reasonable choices for a PR. (Warehouse ET65 might be another?) Depends on how Fendery you want it to sound? IF you want it real clean and Fendery then the Weber 12F125 is a reasonable choice to consider, IMO.

With respect, 10thtx

So you wouldn't go with an Alnico then? What are the celestions like in these amps? V30, green back etc


M

[didit]

So you wouldn't go with an Alnico then?

To complicate the thread---I would, and with high efficiency one as close to D120F or Altec 417 as feasible. Presuming resulting weight is still "grab & go".

Best .. Ian

[joeboo88]

Marcus I put in a greenback in a Princeton clone that I made and it sounds great. The back is almost fully closed. I preferred it that way.

[10thTx]

I had an original 70's PR with a Weber 10A100 alnico 10" speaker. I didn't care for it that much and decided I like ceramic speakers better. It's totally a personal preference thing. Perhaps an alnico with other amps or a 12" alnico and I would have found it to my liking? I don't have much experience with alnico speakers. I do like alnico 2 and/or alnico 3 magnets in single coil and humbuckers though.

With respect, 10thtx

[norburybrook]

Thanks guy's, I bought an Alnico Cream to go with my Tweedle dee and that's a beautiful speaker, I know that will work but fancied something low powered and different like perhaps a jensen or a celestion v30 . I have an EVM 12, an Eminence 150w and an old Peavey scorpion sat here in boxes so I could try any of those first.



M

[10thTx]

From the "Gear Page" so factor that in …………………

And it's supposedly research for a Deluxe Reverb which does use 12 " speakers instead of 10" speakers like original Princeton Reverbs. Perhaps the DR sounds enough to the PR that there would be something useful in this?

I found it interesting. With respect, 10thtx

[norburybrook]

thanks 10thTX

today's progress; Having to think on my feet with this one and hope positioning isn't crucial doing the main board in reverse is testing my Brain power...its all backwards

IMG_20190619_165341-01.jpeg

IMG_20190619_165326-01.jpeg

tomorrows another day. I've got a few components missing so need to wait for them before I can finish. I forgot about all the SM/ceramic caps!!! Doh...



M

[telentubes]

I'm using a Eminence JS1250 in the PR I built a while back and love it. Here is a demo of the speaker...
https://www.youtube.com/watch?v=ITReyFf6iM4
Josh plays through a Morgan Amp which is based on a PR.
Also, I recently changed the cathodyane PI to a fixed bias cathodyne (Martin Manning correction. I said it was a LTP) really making the amp more useful as a grab and go for my needs.

[Colossal]

Also, I recently changed the cathodyane PI to a Long Tail Pair (I know, sacrilege), really making the amp kind of a low powered DR, and find it much more useful as a grab and go for my needs.

What values did you use for your bias and tail resistors? What do you like about the change from cathodyne to LTPI?

[telentubes]

Not intending to hijack the thread but... I did the Paul C Mod from rob Robinette's web site. Scroll down to find it.
https://robrobinette.com/AA1164_Princeton_Reverb.htm
I'm mentioning this because my impression is that Marcus likes amps that have some meat to them (I do too) and this mod made the PR hold together better. I had done some other mods when I built the amp, initially as I wanted to be able to use it with 6L6s (scrapped that and like the 6V6s) so added extra filtering and grid stop and screen resistors where appropriate.
In general, the amp doesn't flub out and has clearer tone, is more dynamic, and has more volume available. The difference was quite notable and for me made the amp way more usable.