Vibration Theory - Isolate or Drain?

Pubul- I never damped a tube amp chassis, only CDPs and pre-amps. I also packed rope caulk around the transport mechanism.

With amps, I usually try to drain out vibration via cones onto a constrained layer platform (Symposium),especially when the Ps and transformers are mounted on the bottom plate of the component chassis.

This is really something you have to experiment with.

CD/ISOLATE
That will be $50 please

I have often asked this question myself. Currently I'm working both sides of the fence so to speak. I have a Mapleshade Samson 4 shelf rack with Heavyfeet thick carpet spikes penetrating through the carpet to the concrete floor below. My amp and preamp both use the Mapleshade model for draining vibration; a maple platform supported by their Isoblocks with cones mounted rigidly to the chassis. My CD player sits on Herbies IsoCups and my DAC is on Herbies Tenderfeet. I also use mass loading in several different applications: HRS damping plates on top of my amp, preamp, and CDP, Mapleshade Heavy Hats sitting on Herbies Grungebuster Dots are on my speakers and power conditioner. This is definitely not my first go round at vibration control, and I'm pretty happy with the present configuration.
I have noticed that the Samson rack is picking up a significant amount of vibration from the floor below. It appears to be 60 cycle hum possibly from an improperly isolated distribution transformer in a nearby electric room. It seemed to me that much more vibration was being transmitted TO the rack than what was being drained FROM it. I contacted Mapleshade with this question and got the following answer: "1. Back in 1986, I did a very careful experiment that proved conclusively that internally-generated vibrations in components have a major degrading effect on sound while external vibrations (in the floor and in the air) have a negligible effect. This is the whole basis of our approach to vibration control.

2. The Samson rack's function is to drain vibration out of every component into the maple shelves and from there down into the floor via the most direct path. Isolating the rack would simply block the vibration path into the floor.

3. Steady-state vibrations or random noise vibrations that are not correlated with the music
have essentially no effect on sound quality (the same is true for electronic noise). It is vibrations that are correlated with the music that seriously degrade sound.

By the way, testing for vibration problems by feeling vibrations (or measuring them with accelerometers) in the component--or by rapping on it (as audiophiles do instinctively with turntables and speaker enclosures) is a total waste of time and never correlates with what you hear. The only useful way to "measure" vibration problems is to change something in the vibration path and then, by listening to your standard music test tracks, determine whether the change improved or worsened the sound of the music. Nothing else works"
I heard a very good point brought up in another forum regarding the draining of vibrations: does the draining occur before or after the detremental effects are felt? Think about that one for a while...

Using rigid devices to "drain" vibration is mostly audiophile voodoo, IMHO, and mainly espoused by those that sell products designed to "drain". Honestly, as someone who has tweaked ad nauseum with all kinds of isolation devices over the years, I am convinced that this is one of the most over-hyped areas of this hobby and one of the least beneficial expenditures of an audiophiles dollars (exceeded only by jitter reduction devices and followed closely by AC conditioning devices). I suppose a brass footer, for example, that reduces to a small point may help (or seem to), simply because it reduces the contact area between a component and its point of contact with the rack. On the other hand, absorbing material used as footers will definitely help prevent the vibrations generated by component from transferring to the rack, but obviously does not stop the source of vibration within the component. To stop the source of the internal vibration, you will have to open the component and damp the offending source, such as a CD transport or power supply. With well built and designed gear (which often equates to "heavy"), I haven't found much need for either internal or external damping. I put my gear on inexpensive absorbent rubber footers (Herbies) and after having thrown lots of money down the rabbit hole, I've discovered there isn't a true need for anything more.

I've come to the same conclusion in almost every particular - but it sure did take a long time to get there.