I agree that stacking the amps is NOT a good idea in terms of heat dissipation. If the amps are high bias designs, i would recommend appr 8" of free space above them. This lets the heat rise out of them unimpeded. In your case, not only is heat trapped in the bottom amp, what does rise out is only helping to cook the top amp. NOT a good thing in any aspect.
Unfortunately, I can't offer any good suggestions. I was also in that boat but ended up changing racks for similar reasons. Since all of my amps ( except two ) are all very richly biased and run hot, i didn't want then cooking to death. As such, i hated loosing a shelf or having a giant "dead space". To correct this situation, i ended up changing racks. I can now adjust the shelf height on several of my racks. This now gives me the ability to accomodate ANY situation or component AND the looks that i was searching for. Sean
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Unfortunately, I can't offer any good suggestions. I was also in that boat but ended up changing racks for similar reasons. Since all of my amps ( except two ) are all very richly biased and run hot, i didn't want then cooking to death. As such, i hated loosing a shelf or having a giant "dead space". To correct this situation, i ended up changing racks. I can now adjust the shelf height on several of my racks. This now gives me the ability to accomodate ANY situation or component AND the looks that i was searching for. Sean
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