I just bought a new PJ from GC and there are a lot of sympathetic vibrations coming from the cabinet. Is this normal for these amps? It doesn't seem proper.

Is it the cab or the tubes?

The spring retainers for the EL84s tend to make some racket. Take it off and see if that makes a difference. Otherwise make sure the speaker is snug on the baffle and the baffle is snug in the cab.

is it essential to keep those spring retainers in there? cause i think thats what makes all the noise in my PJ too....

I'd be willing to bet it's the tubes themselves.
I've had a PJ for about 7 years and it has great tone but it is a noisy sucker! The problem is that EL-84 tubes are inherently noisy to begin with (rattles and such) coupled with the small cabinet of the PJ and it is a fairly loud amp for it's size. there is a lot of vibration in that amp and naturally the tubes get shaken up pretty good. Also the input tube has a good amount of gain set and is somewhat noisy in that amp. If it's that bad I would just try different tubes, I wouldn't remove the retainers, they aren't the problem.

Bob's right the retainers are less of a problem than the tubes. I had a pretty new set of JJ's in mine and they ended up sounding like a baby rattle with every note I would play. So I put back in the Sovteks that came with the amp and although they don't sound as good they don't rattle. The problem with that amp is the small size, everything gets a good shakin.

You can take off the retainers with no real issues the tube sockets will hold them in pretty darn tight. I've had them off mine since the day I got it and havn't had a tube come loose yet. And with regards to the V1 (first preamp tube) you might want to swap it around with another just to find one that might take the beating a little better...process of emlimination with noises...Tubes, speaker, cab...etc.

Good luck! Feel free to email me directly if you have any more Q's.

Tom,

Bob is right on...check that out.

Get a screw driver and tighten every screw, like the handle, back panel, speaker, etc...I would check those retainers too.

Also could be a loose capacitor...they sometimes come loose from the PCB...If that's the case, you would have to to reglue it back down as well as resolder the connections. That is highly unlikely and I would only consider that if the rattle is still there after checking tubes, screws and retainers. I tend to think it's the tubes.

The tubes in my PJ have been rattling almost since it was new, which was 8 years ago. Just for fun, I plugged the blue frame speaker into my Marshall 100 Watt--no cabinet rattle and the speaker sounded pretty good too.

Hey all, thanks for the tips, I'll try them out. I was contemplating returning the sucker to Guitar Center but it sounds like the vibration problems are inherent to the design. This is good, I needed a project today to stave off the madness.

I've been seriously considering having a 2x10 Fender-esque combo cab built for my Pro Jr.

As everyone knows a Pro Jr. into a bigger cab with more speakers SMOKES! I put mine into my Z 2x10 one time for rehersal and WOW!

It may be a good idea to tighten up every screw in the amp. I have yet to buy an amp, new or used that did;nt require some elbow grease to the screws holding it together. I have a Blues Jr. and I love it but when it came I had to disassemble it and tighten every screw in the amp. Also my Vox AC15's and my Dr. Z MAZ 18 required maintenance.

Yep, I'm on it guys, getting down to it right now. I'll let y'all know how it turns out.

I have a Blues Jr and a Maz 18 Jr 2/10, I'll bet some smokin tones will happen if I plug the Blues Jr. into the speakers in the maz. I never tried it yet.

On a side note: I need a Carmen Ghia!!!

i just need to add...i just love my little PJ. mine is the older usa tweed model...it just smokes. its absoulutly the best practice amp ive ever owned. great overdriven tube tone.

Yep, it is a great amp. I think I've managed to reduce the extra vibrations and noise by removing the springs, but the tubes are definitely still making some noise. Time to replace them.

FYI the BEST speaker to put in there is a P10R! It gives it sooooo much more depth! The original tweed ones came with the Eminence Blue frame P10R...mine is a blonde one BTW.

Thanks Lefty, I was thinking of putting a Weber in there. While the early breakup and smooth power amp disortion is cool and all, I would actually have more utility for an portable amp with greater headroom.

I forget where I read this, but it helped my PJ.
Replace the top center screw on the back panel (the one closest to the tone pot) with a shorter one. It reduced hum in my amp. It's still not quiet, but better.
Of my two PJs, my first had very noisy tube retainers, and they both had noisy tubes.

Yep, I removed that top center screw when I first got the amp. Quieted mine down a bunch as well.

As for the speaker, I got a Jensen RI that is rated at 25 watts, not the usual 15 watts like the Weber. It holds up very well in that little 15 watt amp. I get plenty of volume outta that speaker!

As for the center screw thing, all you have to do is take off the back panel and pull the metal "shield" back a little from teh chassis (it's held on with hot glue) and then rescrew the screw back in making sure it goes in between the metal "shield" and the chassis. Otherwise the "shield" gets pushed into the pots/jack by the screw when all the way in, thus making noise.

I need to make a pictorial about doing this.