"Scott Dorsey" wrote in message
...
Richard Crowley wrote:
"Dave Plowman (News)" wrote ...
Keith G wrote:
I meant have you heard a 'tubed' CD player?

I know you've put it in parenthesis, but a genuine
valve CD player would be the size of a house...

And a single tube/valve CD player would consume more
power than all the CFLs in the British Isles are saving. :-)

I dunno. With a sigma-delta system, the main switch and the
integrator
and analogue section are all that you'd have to use tubes for. You
could argue the constant voltage source had to be tubed as well, but
the digital side could be all solid state.

Doing this you could probably do the whole thing in fewer than a dozen
tubes, but the main switch would need to have very wide bandwidth and
a nice square switching waveform. Frame grid tubes wouldn't cut it,
gas tubes are way too slow. You might be borderline for a nuvistor.

But it takes the equivalent of thousands of transistors
just for the motor drivers, head positioning, fine pickup
position servos, etc. etc. Surely doing all that "housekeeping"
stuff with nice warm-sounding tubes will improve the sound
of the output. And, of course, you need a good incandescent
light source, properly filtered and focused, to put some
"life" into those ones and zeroes that are being read off the
spinning disc. :-)

There is more computing power in my optical mouse than
in any of the tube-based computers.