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What's the best way to isolate a tube amp?

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As I anxiously await the arrival of my first venture into tube amplification, I begin to wonder how to isolate the amplifer from vibration. The amp will sit on the same desk as the speakers (can't be helped), so there is definitely some vibration from the speakers to contend with.
So, what's the most effective way to isolate tube amplifers? Dedicated amp stands? Bright-Star Big Rock stands, sand-filled? Air-bladders? Vibrapods? Hydraulic car jacks? Or what?
I've been thinking that vibrapods might not be enough, so I was considering Bright Star Sand-filled platforms..

Any and all opinions appreciated.
Cheers!

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Re: What's the best way to isolate a tube amp? Mike Bates 15:52:16 5/26/99 (3)
Go down to your local hardware store and buy a 18" x 18" x 2" concrete patio block for each amp. In my case, I use two VTL 225s, so I bought two. Also while your there, buy a 16" bicycle tube for each amp.
All you have to do is inflate the bike tube enough so when you place the patio block and the amp on top of it, it rocks back and forth at around 4 hz when you push on the amp.
I have found this combination really works well, I use 3' speaker cables going to my speakers that have a lot of response below 35 hz and if you go over and place your hand on the amp when the levels are high, there is no vibration. There was a noticable improvement in soundstage definition and size, bass response is tighter, and the background became quieter.
- Wait a sec... Tim 09:51:51 5/28/99 (1)
  I have a VTL ST85 and previously have it sitting on concrete blocks.
  Ok, no tire underneath but once I use cones to decouple it from
  the block all the high are smooth as silk now. Bass also
  improve. I suspect that even if you put inflated tire beneath
  it the slab, it still rings like hell from the vibration coming
  thru the air.
  Perhaps even better result can be achieved by combining the
  the tire and cones???
  I heard people said they have excellent result in using cones on
  Seismic Sink...
  - Re: Wait a sec... Mike Bates 07:54:04 5/29/99 (0)
    > I have a VTL ST85 and previously have it sitting on concrete blocks.
    > Ok, no tire underneath but once I use cones to decouple it from
    > the block all the high are smooth as silk now. Bass also
    > improve. I suspect that even if you put inflated tire beneath
    > it the slab, it still rings like hell from the vibration coming
    > thru the air.
    Not in my findings, the inner tube(not a tire) really does a good
    job in damping, decoupling, or absorbing resonance from the patio block.
    
    > Perhaps even better result can be achieved by combining the
    > the tire and cones???
    I agree, the highs do sound more natural and refined with DH ceramic cones beneath them vs. just using the feet that come with the equipment. The DH cones also in my listening take away another layer of haze from the whole sonic picture.
    I should also mention I use the patio blocks with tubes under a CD transport, tubed d/a convertor and tubed preamp. All with DH cones of course. My turntable actually sounded worse with the block/inner tube combination. It is a SOTA Star, the bass is much tighter and extended without the DIY combination. This may not be true for other turntables. SOTA really did their homework in tuning the table's isolation system and the inner tube system made it unstable.
    I do however use a combination of a patio block with 4 large DH cones under it, then a 1/2" layer of Mortite sandwiched between it and another patio block as an isolation base for the SOTA turntable. This combination really gives the turntable a nice non-resonant foundation to sit on and do its thing. The table comes with some nice sorbathane "feet". I tried brass cones in their place and felt it was a step backwards from the factory "nirvana" tuning.
    
    > I heard people said they have excellent result in using cones on
    > Seismic Sink...
- Excellent suggestion and Glad you made it to the Asylum !!! Sean 21:46:37 5/26/99 (0)
  Mike's suggestion should work wonderfully for you. While I'm not using concrete blocks, I am using the bike innertubes. I initially saw this in Mike's setup and was intrigued when I visited him in Ohio a few months back, so I bought some myself and tried it. It was a very inexpensive tweek that really seems to work. I would recommend weighting the top of each component for damping airborne vibrations also. With amps, especially tubes, keep ventilation in mind though. Jon's suggestion of "sandbagging" works great for us folks on a budget. The concrete blocks under the amps should serve as a very dead / non-resonant platform for the amps also, further reducing vibration.
  The nice thing about the innertubes is that, unlike cones and isolation / damping feet, the innertubes offer variable rates of damping, absorbtion and isolation depending on their internal pressures. This is not to mention the incredible price differences !!! You can "fine tune" each innertube for the specific item that is placed on it by altering it's pressure.
  After doing this to my system, I noticed that the system really seemed to be much smoother overall with better resolution. This is not to mention that i can now do jumping jacks or jump up and down right in front of my CD player with NO tracking problems incurred !!! Heavy footsteps and skipping CD's are a thing of the past using this system.
  The bottom line is that they work and can't be beat for the price. A half dozen innertubes and a small hand pump can be bought from K-Mart for about $30 or so. A five gallon pale of sand and some large freezer bags should't cost more than about $10 or so. If you want to get fancy, you can have the "better half" knit some covers for the sandbags. Dyed burlap also works great. For $50 or so, you'll have worked wonders on your system in terms of damping and isolation. Sean
  >
Re: What's the best way to isolate a tube amp? Keith 09:16:28 5/24/99 (2)
Wouldn't vibrapods like melt under the hot bottom?
I know that some people put heavy sand bags on top of tubed equipment, etc., and supposedly it really helps dampen the vibrations.
Ask Hyperion about the Shun Mook. :)
- Re: What's the best way to isolate a tube amp? Barry 18:08:43 5/25/99 (1)
  I like tennis balls their cheap. Barry
  - I used squash balls before... Tim 10:02:17 5/28/99 (0)
    under my cd player. I thought perhaps squash ball absorb
    energy better than tennis ball?
    Anyway, improvement moving from sqashball to cone for my
    CDP is dramatic.
    I know cone (carbon fibre) is probably not the best isolation out there, just want to share
    my recent little discovery.

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