Best way to mound reverb tank in head cab

[Gaz]

I'm using a long spring (9AB2C1B) tank and need to mount it on the 'ceiling' of a head cab (it's Marshall style). I'm having no issues with the sound - even though it's supposed to be mounted other way round - however I do get feedback if it's cranked up loud from vibrations.

The tank has rubber grommets built in, but they're not too substantial. I'm wondering if there's a smarter and more effective way to mount the tank to reduce mechanical feedback, and wanted to get some folks' experience and advice.

Thanks!

[statorvane]

I have a 9AB3C1B (3 springs). I mounted it on the bottom of a cab and have the chassis up above, tubes hanging down (kind of like a Fender Head). No feedback issues. I'd say you probably need to mount the reverb pan upside down. Anyway you can try inverting the cab and seeing if the feedback goes away?

[Gaz]

Thanks for the info. Everything I've read suggests that the mounting orientation does not matter regarding acoustic feedback (if at all), but I will try it for sure.

Do you play yours very loud? I am playing this 100 watter maxed out, atop of 4x12. I think I may try weather stripping across the tank to lessen sympathetic vibrations of the reverb pan itself.

[Gaz]

P.S. Are you using that tank with the standard Fender circuit? If so, do find the reverb tail to be too long (I realize this is subjective).

[Gaz]

Haha, "Best way to mound."

[alvarezh]

I installed my Twin on a Mojotone head. The tank is tightly fit in the head cab and it's enclosed on it's original bag. Have no issues, but I don't play @10 although I have played it very loud.

The tank was originally installed vertically on the side of the combo cabinet (it was a QuadReverb) and so far, doing fine horizontally.

Aside from placing it as much away from the transformer, try putting it inside the purposely built bag and see if it helps.

All the best.

[Gaz]

Thanks, Horacio. The tank is mount on the top of the inside of the headbox. Do people ever put it in a bag then screw the bag to the head cab. Boy, that seems kinda hack...

[ChrisM]

[IMG:640:480]http://img.photobucket.com/albums/v610/ ... CF0323.jpg[/img]

The tank fit by mm's! It was very close to the OT, no extra noise though.

[alvarezh]

The bag comes with a pair of eyelets on each end where the mounting screws are placed, the tank is loose inside the bag. That's the way it was installed on the side of my cab and the way it's installed on my twin and on a friend's twin's head cab I took out of the combo cab. BUT, they are mounted on the bottom of the head cab.

Unless someone else with an experienced opinion comes up with a solution, I am afraid you're going to have to experiment.

Take the amp out of the head cab, install the tank/bag (by inverting the cab on your workbench), and insert the amp back in.

Here is the bag, fourth item down:

http://www.tubesandmore.com/products/reverb_tanks

Another thing, make sure you don't have a microphonic tube, eh?

All the best.

[M Fowler]

My Twin reverb head is very tall so the pan goes into a bag screwed to the bottom of the head cab.

On my very tight spaced Reverb Rocket there is no bag due to space and heat issues. I screwed it to the top as far away from the PT and OT as possible. No reverb pan noise issues.

[Kazooman]

The original Fender stand alone reverb unit has the pan mounted with springs. The picture of the brown tolex unit is an original. The tank is mounted on the front panel of the box. The black tolex shot is of a clone I built. The pan is on the floor of the box. The pic shows how the springs are attached. I am certain you could mount the pan to the top of your head in a similar fashion.

[IMG720]http://i50.tinypic.com/opdeg.jpg[/img]

[IMG720]http://i47.tinypic.com/21dmxbk.jpg[/img]

[statorvane]

Do you play yours very loud? I am playing this 100 watter maxed out, atop of 4x12.

Probably like comparing apples to cinder blocks. I can crank the amp, but it is a P1 eX (10 watts or so, single ended) played through a 4 x 10" cab. I used a modified Fender reverb circuit, and tweaked it to get surf level reverb. No feedback whatsoever. My pan is mounted in a reverb bag, so that may help. I didn't notice much of a change between using the bag and leaving it off, but I didn't have the surf level 'verb at the time either.

[Gaz]

Thanks guys, this is all very helpful, and thanks for that clarification about the bag, Horacio. I haven't had time to try anything out yet but I will post the results... If I can remember, of course!

[Gaz]

Ok, so I was able to solve the issue. First, I tried putting the amp upside down so that the pan was correctly orientated according to the manufacturer's spec. I also place some rubber feet under the cab to provide the same isolation it had righ-way-round. Sure enough with the everything on "10" I could not get the thing to feedback.

So what to do...

After taking the tank out to examine it further, I realized that when the tank was upside down (as I had had it), these white washers mounted on the suspended metal piece would touch the outer black pan. I realized all I had to do was move the springs to a different mounting hole to increase the tension and raise the suspended metal part further from the pan. The pictures below are of what I did. It only took a minute and worked like a charm!

[alvarezh]

Great, good to know, thanks for sharing.

Have a good weekend.