Re: 211 A2 amp



"Nick Gorham" <nick@xxxxxxxxxxx> wrote in message
news:02617ce6$0$26935$c3e8da3@xxxxxxxxxxxxxxxxxxxx
Hi Iain,

I have added a couple of inside pictures to

http://www.lurcher.org/nick/images/211/


Hello Nick. Lovely job:-)

I have sent the pics to a couple of chaps with whom
I share a workshop.

The Tentlabs units are a nice and simple way of heating DHTs,

I asked about these, because, as I mentioned to you before
I want very much to build a good SET and have been collecting
info and ideas for a while now.

AC is cheaper, but I get a little obsessive about hearing hum, and I have
never got hum low enough to not hear it.

I don't think that's obsessive. My own view is that the
amp should be silent from the listening position. It is not
too difficult to build a PP of say 50W which is totally silent
EAS (ear against speaker) but SET is a totally different
challenge.

I find with my open baffles and sitting position, anything over about 1mv
of hum on the speaker terminals is audible.

Yes someone else, Andre I think, mentioned that fig some
while ago. I have given up measuring SNR and now like to
investigate the noise floor in µV. I think it tells one a lot more.

By the way, your note at the link says:
"At 1w the frequency response is 10hz to 37kHz at -3dB, 20hz to 24kHz
at -3dB"

Should this be 20Hz - 24kHz at -1dB ?

My SET project folder is thickening out nicely. I shall be
in touch when I am ready to take the first faultering steps:-)

Look forward to some figs.



Cheers
Iain












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