Re: The Potato Amp?


John Byrns wrote:
In article <1140717246.836709.81270@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>, "Andre
Jute" <fiultra@xxxxxxxxx> wrote:

John Byrns wrote:
Hi Andre,

Please forgive me if I have asked this question before, but how did your
Potato Amp come by its name?

Potato Amp is not the amp's name; it merely describes a single-tube
amp. Any single-tuber is a Potato Amp. It is a pun: tube-tuber-potato.
I don't know who first made the pun. I heard it first from Dan
Schmalle, known as Dr Bottlehead, of VALVE and Elecronic Tonalities of
Poulsbo WA, makers out excellent low-priced kit amps. It is a nice
consideration whether an amp built with two tubes in one envelope (per
channel) is still a potato amp. An example would be Dan's Single-Ended
Experimenter's or SEX; I had a sidebar in my original review for Glass
Audio of the SEX amp on the lexicography of potato amps but the editor
preferred to give the sidebar space to an advertisement...

Hi Andre,

Thanks for explaining the meaning of a "potato" amp so that it could
penetrate my occasionally thick skull.

I would consider "an amp built with two tubes in one envelope" to fit this
definition, in fact I am sort of fascinated by the idea of push pull
"potato" amp using a transformer for phase inversion. Do you know of any
suitable dual triodes, something roughly on the order of two 417s in a
single envelope?

Regards,

John Byrns

Surf my web pages at, http://users.rcn.com/jbyrns/

Tomorrow I'll probably regret answering this now as I am wiped. The
twin-triode Dan chose for the SEX, the 6DN7 is two dissimilar tubes in
the same octal envelope, so it won't do.

The tube that comes automatically to mind is 6AS7 but that isn't
anything like a 417A.

I assume the reasons you choose the 417A must include one or more of
the following:

1. High gain

2. Works direct out of CD (2V signal peak is good)

3. Decent current capability.

Steve Bench built an amp with a bank of 417A but I can't now remember
whether it was PSE or PP.

Tell us more of your parameters. Where would the signal come from, can
your IST be a step up as well as splitter, how much power do you want?

There was a Russian just on RAT, advertising tubes. He sells only
wholesale, I think, but he reminded me of the 6P45S (and similar
numbers -- there is no agreed transliteration of cyrillic tube
nomenclature; try 6pi45C or S too) which is a very beefy little tube,
more like the 417's big but rare and expensive brother the 437A or
167M, but also only a single triode in the envelope.

I'm waffling. I'll hit the books when I wake up.

Andre Jute

.

Relevant Pages

  • Re: The Potato Amp?
    ... Potato Amp come by its name? ... Potato Amp is not the amp's name; ... I would consider "an amp built with two tubes in one envelope" to fit this ... and an anode dissipation rating sufficient to provide a 2 Watt ...
    (rec.audio.tubes)
  • Re: The Potato Amp?
    ... Potato Amp come by its name? ... Potato Amp is not the amp's name; ... I would consider "an amp built with two tubes in one envelope" to fit this ... and an anode dissipation rating sufficient to provide a 2 Watt ...
    (rec.audio.tubes)
  • Re: The Potato Amp?
    ... Potato Amp come by its name? ... Potato Amp is not the amp's name; ... Each section triode mu = 19 while G is about 12 ... grids share a common base pin, so the tube can't be used in a single tube ...
    (rec.audio.tubes)
  • Re: The Potato Amp?
    ... Potato Amp come by its name? ... Potato Amp is not the amp's name; ... I would consider "an amp built with two tubes in one envelope" to fit this ... Each section triode mu = 19 while G is about 12 ...
    (rec.audio.tubes)
  • Re: The Potato Amp?
    ... John Byrns wrote: ... Potato Amp come by its name? ... Potato Amp is not the amp's name; ... Each section triode mu = 19 while G is about 12 ...
    (rec.audio.tubes)