Friends, rodents and other tubies, hail!

The KISS AMP 300B project:
http://members.lycos.co.uk/fiultra/T...mp%20INDEX.htm
is one of many DIY tube and solid state amp projects, and also point
source speakers, at JUTE ON AMPS:
http://members.lycos.co.uk/fiultra/JUTE%20ON%20AMPS.htm

Here is a mainly visual progress report for one of the two amps in The
KISS AMP 300B project:
T39 single tube input/driver stage proving prototype:
http://members.lycos.co.uk/fiultra/K...0T68MZ417A.jpg
Driver stage circuit (potato amp made by subtracting 300B):
http://members.lycos.co.uk/fiultra/t...17acircuit.jpg
Layout suitable for potato (T68) version only (latest hi-cap filter
version of T39 will not fit; the new caps -- see below -- are too fat
to fit between the second choke and the output tranny at the top of the
page)
http://members.lycos.co.uk/fiultra/t68bismzlayout.jpg
Circuit of T39 KISS Amp:
http://members.lycos.co.uk/fiultra/T...trafi-crct.jpg
Transfer function for the KISS T39 Amp for those of you who want to
calculate along with Rudy (go on, surprise yourself by discovering how
little distortion there can be in a SET amp):
http://members.lycos.co.uk/fiultra/112KISScurves.jpg
What lies behind the curves -- the neddy introduction:
http://members.lycos.co.uk/fiultra/K...dre%20Jute.htm
Teach yourself to evaluate transfer curves:
http://members.lycos.co.uk/fiultra/K...dre%20Jute.htm
The KISS T39 original (low-cap) prototype (since transformed into T68
potato above; the interstage transformers shown in the T68 layout went
in the space occupied by big turreted ceramic UX4 sockets for the 300B
in the T39 -- before you ask, the T39 is silent enough without IST):
http://members.lycos.co.uk/fiultra/t39kiss001.jpg
More illustrations:
http://members.lycos.co.uk/fiultra/KISS%20190.htm

An amp like the T39 KISS AMP is not built in isolation:
My DIY horns and other sensitive point source speaker designs for the
KISS 300B amps:
http://members.lycos.co.uk/fiultra/K...20T91HWAF3.jpg
http://members.lycos.co.uk/fiultra/K...Impresario.jpg

For a giggle, five files on a moderately economical fun experiment to
approach DHT sound with a transistor amp:
http://members.lycos.co.uk/fiultra/K...dre%20Jute.htm
http://members.lycos.co.uk/fiultra/K...dre%20Jute.htm
http://members.lycos.co.uk/fiultra/K...20mGBschem.jpg
http://members.lycos.co.uk/fiultra/K...%20mGBmatr.jpg
http://members.lycos.co.uk/fiultra/K...%20NoBleed.jpg

Next I shall design the layout and appearance of the final version, for
which I have a copper plate 13in wide by 1m long.

I'm still trying to use a 17x10x4in Hammond box as a cover for the
gubbins. I'm keen on the Hammond chassis as a cover idea because that
is a promise I made with the original Lundahl Modular Amp series, of
which the other KISS amp, the T44 (circuit and frequency response in
these links, description in main KISS materials) is a development.
http://members.lycos.co.uk/fiultra/T44bis-'Populaire'-crct.jpg
http://members.lycos.co.uk/fiultra/T...x-6SN7-FQ-.jpg

But Patrick's contribution to the T39 power filter (thanks a bunch for
causing me endless trouble, Patrick!), and help from Triode Supply
Japan in finding aliminium cannisters of suitable Solen polyprop
values, have resulted in much more component footage than I originally
contemplated. The original layout, on the left of the photographs he
http://members.lycos.co.uk/fiultra/K...0T68MZ417A.jpg
and in full he
http://members.lycos.co.uk/fiultra/t68bismzlayout.jpg
was already tighter than I like for a circuit published for DIYers. I
might go back to my multilayer 'pagoda' design idea except that I built
a sort of X-plane amp a few years ago, for standing on the cross end
with the tubes sideways on, and soldering in the narrow space between
the plates was a pig; the pagoda design would also require final
soldering in narrow spaces. Well see.

Andre Jute
Jute on Amps at http://members.lycos.co.uk/fiultra/
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