I am sure the input stage is for tube changes unsure about the output stage. If your amp is running at normal warm temperature and both channel heat sinks are the same the output stage should be good.
Well I did say less than 10w 
. I’ve never seen the actual number written down. Could be 1w.
For such a high powered amp i would have hoped about 5w.
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Back in the 90s, I used to own a hybrid Musical Fidelity F15 with 2 ECC88s input tubes. It was rated 2 x 100W RMS class A @ 8 ohms. From memory, its idle power draw was like 250w! The BHK 250 idle power draw is 175W. I struggle to understand how its class A output ends / stops at 1 watt …
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250 watts seems kind of low for 100 watts of class A especially with a tube input stage.
Well I thought I saw it written. That class A was 1 watt. But the masters can correct me.
You’re right. In both amps, the class A bias is just over 1 watt.
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You’re probably right! I ceased using MOSFET based amps for quite a while because they run hot even in AB designs.
I have owned and still do many Mosfet Amps none of them ever ran hot!
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Noted!
Hi J,
Can you spread light onto what the PS Audio tech report/ or via verbal comms means when stated that the amplifier bias was adjusted?
Much appreciated and thank you in advance.
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There are trim pots on each side of the output that adjusts the current that goes through the MOSFETS. We make sure to match each side closest we can to each other.
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