Rattle and vibrations

[TheHunter]

Im having an issue with my combo RM100, It seems to rattle allot at higher volumes at the back panel. When i press my hand to it it does go away.

Does any one have any idea how i could remedy this issue without having to hold my hand on the back while playing. I thought about putting some neoprene padding on it to reduce vibration but i dont want it to mess with any tone then again its messing my tone up now with all the vibrations.

Thanks.

Dustin.

 

[JKD]

Tighten the screws? (Assuming you didn't already)

Take it off casters? (Assuming it's on them)

Get a piece of 2x2 and add a brace from the front to the back panel?

 

[kbause]

are all the screws that hold on the back panel all the way tight?

 

[TheHunter]

I have screwed all the screws in so tight that i fear stripping the wood around them.

The vibration does stop when i place my hand in the center of the back.

JKD i think you have the right idea here. I think what i will do is place a 1x2 across the inside back for stability and then attach a 2x2 from front to back using the 1x2 as a contact point.

Any other ideas.

 

[Jaded Faith]

I had the same issues with a second MTS 2x12 cab I bought. I bought some silicone with adhesive backing from my job and lined all the sections on the cab where the back touches and screws into it. You can get it at www.mcmastercarr.com and it's part number 93755K21. Fixed everything.

 

[TheHunter]

I had the same issues with a second MTS 2x12 cab I bought. I bought some silicone with adhesive backing from my job and lined all the sections on the cab where the back touches and screws into it. You can get it at www.mcmastercarr.com and it's part number 93755K21. Fixed everything.

Thanks Jaded Faith, Im gonna check that out. I think that just might do the trick. I know on the Mesa cabs i ve taken apart, they have some kind of adhesive around the lip where the outter back comes in contact with it and is screwed together. I dont know why i did not think of that sooner Duh! Thanks.

 

[Jaded Faith]

So how did you wind up?

 

[TheHunter]

Well i have the silicon adehisive strip but now i gotta find time to put it in. I should get to it this weekend and ill reply back.

D

 

[TheHunter]

Well i installed the silicon striping and had great results, The back of the combo no longer over reverberates and it seemed to cut down on the friction between the back piece and the combo.

The problem now is that i have internal vibration, but i have some neoprene with adhesive backing i will try out in some strtegic placements for vibration dampening.

I also discovered that on two of my modules i am missing the thumb screws causing a ground break and also exccesive rattling. Ill soon be getting new screws and maybe even try securing the modules with a strip of silicone as well.

I am only going through all this trouble due to the fact that getting a good clean recording means little to no vibration noise. IMHO anyway.

Ill keep you all posted.

 

[JKD]

Your best solution for recording is to use an external cab.

 

[TheHunter]

I have an extension 2x12 that i plan on using. You think it would be best to isolate that cab from the power source and mic the extension? Thats really not a bad idea, i dont have any problems with the extension cab.

Thanks JKD Im goona try to put it in the bathroom or in a closet as i have heard others do, maybe that will eliminate ambient noise and vibration.

D

 

[steprov]

I also have a rm100 with a wicked rattle issue shile I'm playing (more promounced at different frequencies).

I was biasing my tubes and had the amp on but no guitar plugged in. The amp happened to be still at drummer levels.

Now riddle me this batman. I took the screwdriver and tapped one of the screws on top ... rattle. The rattle is definately amplified by the speaker.

The rattle was described by my bandmates as sounding like a "filliment".

Anyway I intend to get to the bottom of this and will be trying some of these suggestions. I also have replacement tubes (winged C and Tungsol 12AX7/ECC803-S) that should be here on Friday.

Little did I know that the mod in moduler amps really meant that is what you need to do to make it road worthy.

Anyway I got my Rm100C for not a lot of money so I don't mind tossing a little more at it as I like the tones.

 

[TheHunter]

I had some major microphonic issues with a module and the amps power tubes, being that its in a combo its hard to isolate its vibrations away from the tubes etc.

I found that if you hear a module rattleing its possible its a preamp tube that has gone microphonic, one way to tell for sure is to pull the tube out and hold it to your ear and tap it. If it sounds loose or you hear it rattling its possible its a bad tube. I did this to all my tubes and found 2 that were potentialy bad tubes, Not saying they wont work but they are more suceptible to microphonic noise pollution.

Also had this issue with the power tubes, Boy they would feed back so bad sometimes, so microphonic i could barely play. I remedied this issue with some silicone rings and that did the trick so well. Also I got some adhesive backed neoprene squares (courtesy of the shop here at work) and applied them to the chassis in various places to help dampen the vibrations and hum created from the speakers etc.

Now I have little to no issues except with the poor consruction of the combo itself, I dont think its meant to handle the rigors of the road, I unplug my combo and use an extension cab and it is just fine, no rattleing of the amps components, no flexing of the open back design etc.

Well just my 2 cents for what it worth.

 

[steprov]

I will say that this amp vibrates like no other amp I've ever owned. It also pushes a serious amount of air.

Can you discribe in a little more detail where you put those silicon rings for the tubes?

I am not going to drag a cab around with me and you it like a 90lb head, but this would be a good test anyway.

 

[TheHunter]

OOOOPS i forgot to tell you where to put the ring.

Put them around the poweramp tubes, You can find these rings all over the place, http://www.tubedepot.com/dctuberings.html

http://cgi.ebay.com/10Amp-Tube-Dampers-For-12AX7-6SN7-EL34-6L6GC-KT88-6AU6_W0QQitemZ110297352791QQcmdZViewItem?hash=item110297352791&_trkparms=72%3A1205%7C39%3A1%7C66%3A2%7C65%3A12%7C240%3A1318&_trksid=p3286.c0.m14

This is just an Idea of what to look for. I actually got mine from the shop her at work.

 

[steprov]

* I replaced the 4 power tubes and the 3 pre-amp tubes (see previous post) on my rm100C.
* I also bought and installed these tube dampers : http://herbiesaudiolab.home.att.net/

The rattle is gone. When I tap the screws like I did before I hear no transferred rattle. I haven't brought it to band practice yet so I haven't subjected it to 5 hours of drummer levels, but prospects look good!

On another note when I had the amp cranked to test it, playing something with some growl like AC/DC, Zep, etc ... my teenage daughters asked me to turn it down. :lol: My answer - "WHat did you say? You want to hear some Iron Maiden?"

 

[jmgman70]

LOL!!!

 

[TheHunter]

Thats great Im glad you found the cure.

CRANK IT UP.

and yes I would like to hear some Iron Maiden maybe the trooper.

 

[steprov]

As a matter of fact that's what I played.

I just realized I didn't say thanks for the suggestions.

Thanks a ton!!

 

[TheHunter]

Im just glad that it worked for you, no need to thank me at all Im just happy that my advice actually paid off for someone other than myself. LOL

LONG LIVE THE TROOPER