[jeffreybehr]

What are they?  And by 'idle', I mean fully turned on but not playing anything.

[jeffreybehr]

Per Bryston--a single 7B3 consumes about 100 watts at idle.

Then--
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(0162010) Mike Pickett (administrator) - 2026-01-28 14:55
https://mantis.axiomaudio.com/view.php?id=146584#c162010
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Hi Jeffrey,

The 28B3 consumes around 200 Watts at idle.

Both units will deliver some power in class A, but it's a relatively small amount and difficult to measure.  As a guess, it would be around 10 Watts for the 7B3 and 20 Watts.  The reason that this is difficult to measure is that there is no change in the performance of the amplifier, including THD+N and IMD, when it switches to class AB.

Thanks,
Mike"

And FWIW and as I understand it, his use of "switches to class AB" is not exactly accurate, as nothing in the amp does any switching.. A more accurate way to say that would be 'eases into class-AB operation'.. Nelson Pass has written fairly often about this; here is one I found quickly and probably is worth reading.
https://www.firstwatt.com/wp-content/uploads/2023/12/art_leaving_class_a_2019_redux.pdf

So for MY situation, a 7B3 draws only 27% of what my Pass XA60.8 draws* at idle and about the same as a 110watts-into-8 Linear Tube Audio model Century that I'm fantasizing about.

* and even a 28B3 draws at idle only about half of what that XA60.8 draws.