put tube amp on to shelf of a rack

Tube-amps need “fresh air”!!! It’s very important to put him away from other equipments.  The heat of the tubes can cause damage in this setup. Place the amp on a separate tray. You can find them on rubber wheels. ( like ebm and aewarren,..said)

@lukaske @aewarren @backtothe80s @jnorris2005 @jond  @mboldda1  @twoleftears @facten  Thanks all for the additional input! I decided to just put the amp on the floor beneath the media console for now where it should have enough air flow through it. Hope this works well! 

"How to keep the mega-amp from cooking anything above it."

'Puter fans.  Pick the quietest you care to.  Works for my SS stuff, no reason it won't for the toastiest of tubes....

Mount an array of them in a rack module, put it at the back.  On a cold night, a 'forced-air' heat source. ;)

Might extend the life of the fire-bottles in the long run....

You're welcome. *S*

Go to the gym more.

asvjerrry is correct.

TWO 12VDC 100mm [or 120mm or 140mm] fans  run on 3.5VDC. One either side of the amp PULLING air AWAY from the amps will keep them and the equipment above sufficiently cool.

FAN: https://www.amazon.com/gp/product/B019SY0TAO
PSU:  https://www.amazon.com/gp/product/B01G7KT0V6

IMO, the curved fan blades as shown are mandatory. I've been actively cooling HiFi and other electronics since the 1970's. Curved blades are the quietest in this application.

I have 5 such fans for my 3 tube and 1 ss amps in my Tri-Amped rack system. My media room is sub-40dB. At 1 foot from the amps, the fan noise is neither audible nor measurable. See http://ielogical.com/assets/Audio/FanCtrl.jpg for a "Power Distribution" example.

105 pounds atop a stand not much larger than the amp footprint is a severe earthquake hazard.