Tube amp vibration absorber?

[JimmyM]

I have a flatback and it doesn't vibrate at loud volumes. But I wouldn't be going too darn loud with a flatback. While I think they can do better than their rated 250w power handling, I don't think they do much more than that unless you change out the speakers for something more heavy duty. But that changes the sound and who wants that?

Anyway, listen to Paul. He's on top of things. Almost all tube amps are shock mounted, and there's really nothing to worry about unless your cab is just crazy shaking. And if that's the case, I'd be wondering if there's something wrong with the cab structurally. However, if it makes you feel better about it to put something in between the head and the cab, nothing wrong with that.

 

[Downunderwonder]

D180 is not shock mounted so far as I can see. Big precision rack box, circuits bolted on. "Ready to be shot to the moon" was the original reviewer's desccription.

 

[d180fuzz]

Paul - perhaps I've read things you've posted, misconstrued the spirit of what you said (and likely disagreed as well), and made a quick judgment. I apologize.

This thing we all love incites passion in us, and it can be difficult to reconcile opinions and see things objectively sometimes. It's clear that at least a couple of the folks that I consider TB gurus know you better than I do and trust your statements.

Jimmy - I have, in fact, loaded the bottom half of my flatback with B810s - coupled with switching back to my old L2000, it's suddenly quite a bit louder and more present, and while it's not at all vibrating like crazy, I do notice some resonance when playing certain notes.

You're right, DUW - a D180 is a rack-mounted job with no bushings or other isolation built in (unless you've got it in a Boogie SUS-4 rack or "foam" rack). Mine's in a plain 5-space ATA rack with nothing else.

It'll probably make me feel better to just grab some of that sorbothane stuff.

Thanks everyone. Sorry for wiggin' out.

 

[Foz]

The best place to fix a vibration/noise problem is at the source.

 

[Downunderwonder]

The best place to fix a vibration/noise problem is at the source.

Turning down probably isn't an ooption.

Likewise bracing the floor.

Which takes us back to bracing the cab.

 

[Leized]

Personnaly, I use gel rest arms pads for computer keyboard. Quite inexpensive and shock absorbant.

 

[MAMMOTHvolume]

If you don't wish my advice coming from fifty years of experience playing bass or my forty odd years of engineering then please, by all means, add me to your ignore list.

I don't do "know-it-all" posts. That fact that you regard them as such puzzles and saddens me. I come here freely to help my fellow brothers and sisters of the bass. What I post is true fact as I know it.

+1 you know your stuff, it annoys me people choose to ignore knowledge and doing things right in preference of finding a solution for something that shouldn't be an issue!

 

[BassmanPaul]

d180fuzz, i accept your apology and give my thanks to the folk who gave me support. It shows me that i'm not wasting all the time I spend here.

 

[Chef]

Disagree.
My Fender Bassman 50/100/Dual Showman weren't; the new SuperBassman aren't.
MusicMan HD weren't.
My Mesa 400/400+ came from Mesa in what amounted to a wood and tolex headcase; as does the SVT I believe.

I never had a vibration related issue with any of those when I was gigging them; fwiw.

Almost all tube amps are shock mounted,

 

[Passinwind]

Here's the question: does anyone have any suggestions for a material I can use to isolate my tube amp from the seismic vibrations my cabinet produces when I'm forced to put the amp on top of said cabinet? I'm thinking some sort of thick rubber material, but not sure how to find it.

Start Invalid Link Removed and here.

 

[chaosMK]

I just use a folded up towel or some sort of sturdy folded up cloth-like material. I always do this with my tube bass amps.

 

[JimmyM]

Disagree.
My Fender Bassman 50/100/Dual Showman weren't; the new SuperBassman aren't.
MusicMan HD weren't.
My Mesa 400/400+ came from Mesa in what amounted to a wood and tolex headcase; as does the SVT I believe.

I never had a vibration related issue with any of those when I was gigging them; fwiw.

Wow, didn't know that...I figured it was somewhat standard. SVT's do have shock mounting, though.

 

[aborgman]

Uh huh. Where do I begin?

1) I'm not sure what volume you currently play your amp at, but I play mine quite loudly. At this volume, it vibrates. It's also an old flatback SVT, so....it vibrates.

...and it shouldn't.

Any cabinet vibration is a symptom of inadequate bracing.

3) I realize my tube amp isn't made out of glass - but the tubes providing that awesome tone I want are - and they're what I'm concerned about. A cursory search via google reveals multiple patent applications for devices to isolate cathode ray tubes from shock and vibration.

Well - A CRT is quite a bit different... and most of the tube shock absorption patent are about as technically well though out as a pet rock.

4) Just because something "never entered your head" doesn't mean it's invalid or untrue. In fact, quite often, the opposite is the case.

If (like Paul and I) you've been building, using, and repairing these things for decades... if something never entered out heads, it's most likely invalid or untrue.

Tubes just aren't that susceptible to vibration. If you aren't hearing microphonics, it isn't an issue.

 

[rodl2005]

I've had tube amps all my 35+ yrs gigging & the li'l rubber feet on the bottom of em is all I've ever used.

I think even my old 70's Bassman has metal feet, so-even less shock padding there.
It's got it's 2nd set of power tubes now, the originals I changed out about 10 yrs ago.
Must be pretty robust! :thumbup:

 

[OogieWaWa]

Something for thought: I made this base. Some air compressor mounting spacers I found that isolate vibration, mounted on a piece of 5/16" Lexan. The amp relies on cooling air from the bottom, so I drilled a bunch of 1" holes in the Lexan under the vent. So this helps both cooling and vibration; the feet on the amp don't allow a whole lot of clearance when sitting on rat fur. Oh, and I had a couple of green automotive LEDs and a 12v wall wart laying around, so it glows, too. Tinkerer, musician and being frugal are a nasty combo.

It does mean lifting a tube amp 1.5" higher, though, ugh!

Link Removed

 

[beans-on-toast]

These hydraulic glides look interesting if you don't mind modifying your amp or cab. The price is right. Same idea as what Ampeg used in the early days and still use on some amps.

 

[nojj]

I use a piece of playground mat.
Works great for decoupling amp from cab.
Use the same stuff under the older round mic stands,
and a couple pieces with my HD recorder when recording live.

Usually available in many colors.
I'd gotten quite a lot of it when making a 'foot fatigue reliever' around my table saws.

 

[Foz]

Foz: The best place to fix a vibration/noise problem is at the source.

Turning down probably isn't an ooption.

Likewise bracing the floor.

Which takes us back to bracing the cab.

That's the point re-stated. But you don't get "back to bracing the cab" - you start there and stay there to fix the problem at the source whenever possible.

Its a standard engineering maxim for addressing vibration problems... first try to fix it at the source = costs less / works better.

If your cab mechanically vibrates your amp [or the stage] so much its a problem... then the cab is the problem... skip all reference to other elements and you are where you need to be to take your first wack at a solution.

Likewise, if the outside half of your AC rattles/buzzes so loud it bothers you when you try to sleep - then the AC unit is THE place to try and solve the problem [get a better fan/motor, repair the fan bearings, repair/upgrade the vibration damping on the compressor and or fan's motor mount] versus for example, trying to increase the transmission loss characteristics of you bedroom's walls/ceiling/windows/floor-slab... because when you fix the source all the other failure paths become moot.

And thus, yes, repairing/augmenting the cab's bracing would seem to me to be the standard engineering "try first" solution.

==

Much is said above about vibration not being a problem in bass rigs - and it certainly shouldn't be, but that said, vibration is a corrosive influence = a standard "test to failure" mode.

https://www.youtube.com/watch?v=W31Hkh2jv00

Excessive vibration will absolutely reduce life cycle in anything as remotely fragile as an amplifier - tube or SS*.

*though I wonder what components would be worst treated by such... as explained above "some" tube components are very resilient to vibration.

 

[heynorm]

Go to a toy store/department. Buy two baseball-size rubber balls. Cut in half. Place on cab under four corners of head. That's how we did it in the 60's.

 

[P-oddz]

Not to hijack the thread - but since my issue has to do with unwanted vibration thought I'd give it a shot here.

Problem: What is most likely tube retainer clips vibrating off of tube(s) in AD200b head.
Question: Is there any product available to absorb vibration from the springs (some O ring perhaps, or something to that effect)? New retainer clips? Different retainer clips? Would I just be better off finding something that isolates the head from the cab as mentioned in this thread previously?