Discussion:
Lesmann Echo Amp for accordian
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l***@gmail.com
2019-05-18 18:23:30 UTC
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I'm looking for any info about Lesmann Echo Amps. They were built in the 60's for use with the Lesmann accordian. I am in the process of trying to restore one and am having little luck finding anything about them anywhere.

Thank You
DoN. Nichols
2019-05-20 01:05:24 UTC
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Post by l***@gmail.com
I'm looking for any info about Lesmann Echo Amps. They were built in
the 60's for use with the Lesmann accordian. I am in the process of
trying to restore one and am having little luck finding anything about
them anywhere.
Given the vintage -- the first thing would be to replace all
electrolytic capacitors in the amp. They tend to dry up and fail. If
the power filter caps are dead, you will get a lot of hum. Others could
affect the frequency response and other things -- including greater
distortion.

Probably not much difference circuit wise between an accordion
amp and a guitar amp of the same period.

A quick search for schematics or manuals on the web failed, so
the electrolytic cap replacement might be all that is needed -- and
almost certainly *is* needed, even if there are also other problems
there.
Post by l***@gmail.com
Thank You
Good luck,
DoN.
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l***@gmail.com
2019-05-20 02:52:15 UTC
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Post by l***@gmail.com
I'm looking for any info about Lesmann Echo Amps. They were built in the 60's for use with the Lesmann accordian. I am in the process of trying to restore one and am having little luck finding anything about them anywhere.
Thank You
Thanks Don

What I really need is info on how this beast hooks up to another amp or accordian. It is like no other amp i've seen. There is no input jack of any kind. Not the six pin jack like the Lesmann organ amp or any 1/4" jacks like other amps.

There is a hole on the bottom of the chassis and inside it looks like some wiring was cut out there.

I'm hoping some oldtimer like me saw or used one of these back in the day and could clue me in to its use and hook up. There is NO info anywhere on the net that I can find so this must be a real rarity even for a Lesmann.

Thanks again for your help!

Dave
DoN. Nichols
2019-05-20 23:34:36 UTC
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Post by l***@gmail.com
Post by l***@gmail.com
I'm looking for any info about Lesmann Echo Amps. They were built in
the 60's for use with the Lesmann accordian. I am in the process of
trying to restore one and am having little luck finding anything about
them anywhere.
Thank You
Thanks Don
What I really need is info on how this beast hooks up to another amp
or accordian. It is like no other amp i've seen. There is no input jack
of any kind. Not the six pin jack like the Lesmann organ amp or any 1/4"
jacks like other amps.
O.K.
Post by l***@gmail.com
There is a hole on the bottom of the chassis and inside it looks like
some wiring was cut out there.
Hmm ... likely had a connector on the bottom to connect to
whatever it sat on. Perhaps it was the accordion itself, or perhaps on
a speaker box.
Post by l***@gmail.com
I'm hoping some oldtimer like me saw or used one of these back in the
day and could clue me in to its use and hook up. There is NO info
anywhere on the net that I can find so this must be a real rarity even
for a Lesmann.
I did see one find offering ways to convert such to act as a
guitar amp -- it might have enough information to help you.

Oops -- it was an offer to sell one, not how to modify one:

<https://reverb.com/item/994148-vintage-1960-lesmann-accordio-organ-25w-1x15-tube-combo-amp-tweed-killer>

It is already sold -- but if you scroll down a bit, you get an
image of it -- and a bunch of others which show various things about it.
Do these look like what you have? From the photos -- there is a phone
jack on the front panel at one end for inputs. And I guess that it
connects to the speaker under it via the hole with cut wires, which was
likely a multi-pin connector.

O.K. -- forth photo in the row of thumbnails below the main
image. Looks like (from the left to the right):


======================================================================
Fuse holder

Power switch

Pilot light

five pots (likely two gain for two inputs, tone controls, and perhaps
echo level)

two phone jacks for inputs

multi-pin connector for outputs to speaker (at a guess, a four pin round
jones plug
======================================================================

The metal cover to the left of the three transformers likely
covers a reverb spring for the "echo" effect. (in the 6th photo)

Do the cut off wire go to the transformer just to the right of
the reverb cover? I think that is the output transformer, so those
would be speaker connections.

Hmm ...also one more phone jack between and below the middle two
7-pin miniature tubes, and two more connectors between the power output
tubes. (Maybe those are the connections for the speaker in the box. if
so, the multi-pin connector may carry power to the electronic accordion.
In that case, they would be a low voltage for the filaments in the tubes
(6.3V or 12.6V likely) and a higher voltage for the plates of the tubes
in the accordion -- like 140 to 180 VDC

While I'm a bit of an old-timer (78 currently), I was not an
accordion player -- but rather an English Concertina player (one of the
reasons this is rec.music.makers.squeezebox -- it was formed to be
friendly to all bellows-driven instrument players -- and only after it
was formed did we discover that some accordion players objected to the
term "squeezebox". :-)
Post by l***@gmail.com
Thanks again for your help!
Dave
I hope that this helps a little. We've run out of what I think
I can determine (or guess) from the photos and what I know of old tube
electronics.

Good Luck,
DoN.
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Excelsior960
2019-08-09 21:57:17 UTC
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hello lapst,
hello DoN

the lesman organ accordion was a very short lived
boat anchor of a solo polyphony transistorized
attempt to rapidly compete in the new and hot
category created by the Cordovox

the accompanying boat anchor of an Amp also
supplied power to the very basic organ tone generating
circuit board in the accordion itself

as far as re-wiring the old amp, just test the
connection wires you can find for ground and voltage

dont use the one with positive voltage (lol)

use the one that has no voltage but makes the amp HUM
when you grab it with bare fingers

PS: their stuff was incredibly noisy and cheap,
and while your project will be fun, it will likely not be
actually useful beyond crude, rude, maybe loud,
and thundering spring reverb kick the amp FX

ciao

Ventura
DoN. Nichols
2019-08-10 02:31:36 UTC
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Post by Excelsior960
hello lapst,
hello DoN
the lesman organ accordion was a very short lived
boat anchor of a solo polyphony transistorized
attempt to rapidly compete in the new and hot
category created by the Cordovox
the accompanying boat anchor of an Amp also
supplied power to the very basic organ tone generating
circuit board in the accordion itself
as far as re-wiring the old amp, just test the
connection wires you can find for ground and voltage
dont use the one with positive voltage (lol)
use the one that has no voltage but makes the amp HUM
when you grab it with bare fingers
And don't use one which makes *you* hum when you touch it. :-)

O.K. I forget who actually asked about it. Apparently "lapst".
I was trying to guess reasonable things to do with it -- assuming that
it was worth while.
Post by Excelsior960
PS: their stuff was incredibly noisy and cheap,
and while your project will be fun, it will likely not be
actually useful beyond crude, rude, maybe loud,
and thundering spring reverb kick the amp FX
Well ... we'll see whether the original poster wants to go ahead
with it or not.
Post by Excelsior960
ciao
Ventura
Thanks (& squeeze on),
DoN.
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Excelsior960
2019-08-11 02:19:01 UTC
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DoN

can you hum a few bars ?

nice to see you still around and posting

i hope all is well with you and yours

ciao

Ventura
DoN. Nichols
2019-08-12 02:00:05 UTC
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Post by Excelsior960
DoN
can you hum a few bars ?
Only with 60 Hz applied to my fingertips. :-)
Post by Excelsior960
nice to see you still around and posting
Still around -- as are you, apparently -- good to se.
Post by Excelsior960
i hope all is well with you and yours
Well enough, at least. And you?

Squeeze On,
DoN.
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