Princeton tips, anyone?

[zebpedersen]

There's been a few threads in recent weeks concerning the rare-as-hens-teeth Princeton Boost amps Randy was turning out of Prune Music back in the day, which have inspired me to leave the stereo Mark II/D-type bi-amp rig in the corner and bust out my own Silverface non-reverb Princeton for some oldskool vibrato action.

It's such a great sounding amp with a terrific vibe, and I want to build a new rig around it. Do any of you (possibly of a certain age ) guys have any tips for getting the best out of this thing?

I know Randy used to strengthen the cabs and upgrade the speakers - anyone got any details? Sticking a Big Muff though this thing sounds killer, but the cabinet sounds like it's gonna shake to pieces! I'm thinking of getting a TS of some sort, and a replacement 10" speaker.

Any suggestions would be much appreciated. And seeing as posting pictures seems to be in fashion, here's one!

 

[Don]

I had a 1968 Pinceton Reverb that had an annoying buzzing vibration. It turned out that the Tolex had come unglued around the speaker baffle. I re-glued it with contact cement and the problem was fixed.

I've also seen people reinforcing the back panels on new PRRIs.

Have you tried the amp without the back panels to see if they're the problem?

 

[Restless Rocks]

Those early Silver Face Fenders are coming into their own these days as they are getting more scarce in all original condition. The first SF's were pretty much same spec as the coveted Black Face amps of the mid/late sixties. If you have the original Jensen P10 speaker in there be careful cranking on the amp cos you will blow the voice coil pretty easily when maxing out the volume. Obviously the first thing to do would be to replace all the "lytics" or "recap" it especially if it has sat for many years without being powered up. The Princeton Boost amps Randy built began by pretty much gutting the chassis and installing transformers for a much larger 6l6 or 6550 power section and cutting out the baffle for a 12" speaker.
My recomendation would be that given the vintage value of those amps now I would recap it and leave it stock as they are gaining value every year. The Fender Blues Jr. will find the vibe (are cheap and easy to get) of a cranked princeton or deluxe. On the other hand there are sites such as Schematic Heaven where you can find dozens of mods for the fender circuits.

 

[Monsta-Tone]

I would check all of the tolex, around every edge. Even the 3M spray on contact cement would do if you were careful with the overspray.

Also, tighten every screw. The baffle screws, the feed, handle, everything. See if that helps.
Do not over tighten them though, the cabinet is pine and the holes can strip out very easily.

If you have a screw hole that is stripped out, that may be where your noise is coming from. Take a toothpick and dip it in a little wood glue. I like to use Tite-Bond. Put it in the hole and cut it off so that it won't stick out of the top of the hole. Then put the screw back in. Problem solved.

I would replace the caps for sure!
Then, I would call Weber and talk to them about a replacement speaker.
Tell them if you want more or less breakup and they will get you the right speaker.
Then, put the original one in the Weber box and save it for resale.
Finally, play the hell out of it and crank it, knowing that your caps and speaker are ready for action!

 

[RR]

Other than a re-cap, I would not change a thing for value and tone purpose.

I have a '68 or ''69 (these have a thin aluminum lining around the grill) I just love the tone it capture that rock n' roll mojo, Johnny B Goode, Surfining USA, House of Rising Sun especially CCR. Once you start modding it, it starts getting away from that Princeton tone. ... and the Princeton SF design did not change much from its BF design.

If you want more tone out of it say more bass, try playing through an external enclosure 1-12". Problem playing through hi-powered speakers, those handling higher wattages, you lose that 'speaker breakup' you are used to from these Princetons. You gain headroom but lose 'rock n' roll mojo'.

I played mine through JBL K-120, EV-12L, and assorts of Eminence, seems like the stock Fender Oxford[?] was it best tone for me. It had that natural break up for a 60's rock n' roll tone.

But later, I purchased a Weber 12F125 (30 watts?) cheap from a internet garage sell and played my Princeton through and it was similar to the stock Oxford Fender but since it's 12", a little more bottom end.

So cap job, and play through external speakers.

If you need more gain out of your Princeton, try stomp boxes. Try stomp boxes with a 12AX7 pre-amp tube since these early Boogie (as well as today's) has cascading preamps.

oh zebpedersen, nice Tele.

 

[zebpedersen]

Thanks for the replies so far guys, all good stuff.

Just to clarify - I'm not going to mod this amp to try and turn it into a hybrid/Boosty-type affair or anything!

I'll definitely check the cabinet to see what's vibrating. What are the odds of the 5U4 needing replacement? I'm guessing it's had a pretty easy time of it seeing as that power stage isn't exactly massive, but might that be an idea? I don't have any other tube-rectified amps.

As far as the caps getting replaced, this thing is dead simple inside, I'm no master-solderer or amp-wizard but it looks like it might be 'user-serviceable' (if anyone wanted to give me a couple of tips, perhaps if I post a gut-shot?)

Looked at Ted Weber's site, but I'm probably gonna have to look somewhere in the UK for speakers because of shipping. Looked at the Jensen P10R AlNiCo (£65 from HotRox), as someone mentioned above that Fender used to ship older Blackface amps with Jensens (not to mention the fact that Boogie shipped Jensen 10"ers in the 4x10 Rocket 440). Anyone know if there's a modern 'direct replacement'? The stock Fender speaker isn't great at handling low frequencies, but I know there are speakers out there which can from experience of my Subway Rocket.

Cheers!