Lowering Tube power amp output

@tubelvr1 The more powerful you make a tube amp (unless its an OTL) the more limited its bandwidth becomes, due to the output transformer.

What this means is that for the most part smaller tube amps sound better (except for OTLs where bigger ones sound better).

So rather than remove tubes to reduce power getting a smaller amp is good advice. FWIW the output transformer is designed to provide a certain load for the power tubes provided its output is loaded correctly (for example an 8Ohm speaker is connected to the 8Ohm taps). When you remove tubes that load that the transformer provides will change and so the remaining tubes won't be loaded correctly and most likely will be too low of a load for the remaining tubes. This will lead to excess distortion, the tubes running hotter and their reliability compromised.

So don't do it!!

Drop in some Kt-77's  There cheap now also

I’ve heard you can start removing push-pull pairs on each side (normally 3 push-pull pairs per side), but as noted this will be suboptimal. You’ll have to re-bias if you do this. You can also just drop the tube biases down from the standard 40mA to say 35mA, for a slight reduction in heat. Rogue is great to chat with if you want their guidance on this. 

If you’re concerned about heat dissipation, an amp with a dozen KT88 and 6 small tubes is not a great match. As others have suggested, it’s probably a good idea to trade the amp in. Many audiophiles without heat concerns would love to have that amp!

Electric cost your concern for ac? 

It is frequently over 90 degrees outside… my partner is disabled and uncomfortable so I keep the house at 70 degrees. Even so, my electric bill (with 100 hours of 36 tubes… 8 KT150s running) is less than my Verizon bill, insurance bill, property tax bill, Comcast bill… How is this an issue? Too much bass?