Anybody put thin damping sheets under their BH top plates?

[Downhome Upstate]

I read a post here recently,  bug-nuts BTW, where the poster was complaining about vibrating iron, etc.  (That's the one where Doc chimed-in with an anguished cry of inadequacy.) Leaving wacko stuff out of it, some isolation or damping can be a good thing.

What do you guys and gals think about, e.g., putting some thin strips of 0.8 mm Herbie's Grungebuster sheeting under the edge of the top plate where it fits into the wood base?

Doc, I'm going to hide behind the garbage can waiting for your answer.

[galyons]

I have strips of automotive audio damping under my Foreplay.  (RAAMat...left over from a vintage sports car restoration. I also use it elsewhere in the system, including on the frame struts of my OB woofers.)  Does, to me, make an audible improvement. The early aluminum plates were relatively thin and the damping material helped!

Cheers,
Geary

[4krow]

Actually, I have used vinyl damping sheets sourced from Parts Express for this purpose. I used them on a Quickie project, between the wood cabinet and the faceplate. Just makes sense to keep vibration at a minimum with microphonic equipment.

[Paul Joppa]

Just a note - vibration damping materials are very sensitive to temperature, having a fairly narrow range within which they are most effective. That's a good reason to look at automotive parts made for engine compartments, for example.

I first learned about this working at Boeing; the passenger cabin skin has damping sheets on the inside surface, and the air at 30,000 feet is COLD!

[4krow]

Paul, That did cross my mind, but I figured to use it anyway. As it turns out, it did seem to help out. Also, for sake of application, I used a heat gun to make sure that the sticky side stuck. This does seem to help the sheet adhere completely.

[rif]

Grungenbuster has a temp range of -80F to 400F (i just happened to be on that site while reading this).

[Paul Joppa]

Grungenbuster has a temp range of -80F to 400F (i just happened to be on that site while reading this).

Well, I'm sure it won't melt below 400F nor shatter above -80F.

Engineering materials for vibration control usually specify the real and imaginary parts of the Young's Modulus as a function of frequency and temperature. Without that, there is no way to design an application, so I remain skeptical.

Not to say it won't help.

[Chris]

Blu-Tak can work also...

[Jim R.]

I've had decent results with grungebuster in the past -- and I had Steve make me up some thin rings of the stuff for some tube sockets, which I'll probably use in my quickie.   I would still use something like dynamat to cover a large portion of a plate or chassis as the grungebuster seems to be far more effective between things then just on them.

-- Jim

[4krow]

I was using Dyna-mat on the inside of metal covers when I worked on some of the units I was selling. It worked good enough, but then I tried another product. It is a vinyl damping sheet that is cheap. Really, I was quite surprised when it performed much better in this case. Just saying it doesn't hurt to experiment with a few products to see which marries up the best.

[akomarek]

The only benefit I could see from adding damping material to the top plate would be to reduce tube microphonics.  Don't think it would matter with a headphone amp but if the amp is powering speakers the sound pressure could excite the top plate and perhaps induce some structure-borne microphonics into the preamp tube.