Don Foreman wrote:
On Sun, 01 Jan 2006 03:47:18 GMT, "Tom Gardner"
wrote:


See it your buyer wants to buy my copy machine. I still have a box of
negative paper for it and 2 quarts of developing fluid...I forget what they
call the process but it 'kinda worked. I also have a CP/M computer with
SSSD 8" floppy drives and a 9" mono composite monitor, hand built-worth
more! I also have a TUBE TESTER!

Gunner, here's the phone number for BFI in your area:XXX-XXX-XXXX If you
call them, I will too.


There are some audio guys and musicians (guitar amps) that *WANT* that
"tube sound" and pay large to get it.

I thought that was fetish bull**** for quite a while. After finally
studying the matter rather than smugly hooting, I now see why "tube
sound" really might be more pleasing to some or most. It's not the
same as the gold plated power plug stuff which is utter bull****.
Tube amps don't intrinsically distort any less than silicon amps,
but they do distort differently -- and the difference in relative
strengths of various harmonics (distortion) is more "musical" to
some ears. One key to this is "balancing" some of the tubes,
particularly the output tubes which often run in matched pairs. A
good transconductance tube tester would be very useful for selecting a
best-matched pair out of a bunch of found tubes. The cheaper
emission testers were really only good for weeding out dead or
near-dead tubes at the drug store. I don't know which flavor Gunner's
is, but being B&K I'd suspect that it's a good one. If there's
something on the meter that says gm, bingo. Gm is
transconductance.

Don Foreman -- who is struggling mightly (while whining miserably and
bleating pitifully) to learn to use microcontrollers and program in
C, but designed tube circuits many moons ago and still has the RCA
tube manuals.

Repairman at a sound company and i do live sound.
Still ahve that bench set up amongst my others and i am setup to do
almost everything but PCB's (tubes through test circuits when needed).

Don you are dead right the "Guitar" sound has nothing at all to do with
fidelity of reproduction of the original sound. Guitars and guitar amps
(Even "Clean" ones) are more about getting a distorted instrument sound
thats pleasing to the ear (Even harmonics instead of the odd harmonics
produced through switching)

Fidelity only kicks in at the microphone facing the amp and at that
point its treated as a separate signal source and whatever distortions
the guitarist wants are now treated by the sound guy as the "signal"

As a result those distorting footwarmers of tube amps do that job
perfectly where integrated circuits are much better suited for
reproducing sounds with fidelity to the signal rather than adding their
own "Warmth"