OTL ,Transcendent,Atma-Sphere,orBearning

Check out the David Berning equipment. The ZH-270 may be just what you need. It produces 70W @ 8ohms. It also increases output as the load increases, unlike other OTL's in which the opposite applies. The ZH-270 sounds incredible in every aspect. It truly has the drive of no other amp I have heard. Check it out even if you love your Atma-Sphere dearly. This one won't run hot or take any serious toll on your electric bill, unlike most OTL's. Worth looking into, at least from what it sounds like on your post. Best of luck :)

I vote for Transcendent Sound. Compared to Atma-sphere, it has three advantages: Less heat, more bass, more lively sound. Go for it.

I have not heard either the Berning or Transcendent equipment. I use both the Atma-Sphere amps and their preamplifier and find them to be very satisfying. They seem to do everything right. Be sure to audition the amp/preamp pairing if you have not already done so. Also, be sure to factor in the savings obtained by using inexpensive microphone cables when connecting an Atma-Sphere preamplifier to Atma-Sphere amps. My cables (Mogami Neglex recommended by Atma-Sphere) cost $100 for a 50' pair. I have found the heat distressing only when the seasons change as I am forced to choose between A/C or heat from my heating/cooling system. These are astounding products and I believe deserve careful consideration. God bless.