Geloso G1 1040 mods

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firticchio
Posts: 1
Joined: Wed Jun 12, 2013 1:58 pm

Geloso G1 1040 mods

Post by firticchio »

hello everyone
I have a geloso g1 1040 50w that after few mods (preamp stage for guitar use and changed the exaust electrolitics) for functional test i would complete modifying.
the trasformers specs are
PT: 6v-6v 4A, 332v-332v 270mA, 39,2v-39,2v 150mA
OT: 4000ohm - 50-60w
choke: 3H

I already have 2 matched 6550, 2 matched kt88, several 12ax and 12au7, further the geloso original tube.

i attach the original amp scheme, the scheme with the mods i did for a test and the scheme with the idea for a 6550 mods (the power section need tweaks)

any advice for an amp whit this trasformers and with my ideas?

thank you and sorry for my bad english
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hobbits
Posts: 1
Joined: Mon Mar 03, 2014 8:34 pm

geloso 1040

Post by hobbits »

i'm a geloso 1040 owner also. Do you have a sound sample or video of the normal / bright section mod. you made?. Maybe i will do the same.

greetings Peter
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modman
Posts: 45
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Location: Hoegaarden, BE
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Re: Geloso G1 1040 mods

Post by modman »


Last edited by modman on Mon Aug 13, 2018 3:53 pm, edited 2 times in total.
modman
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Re: Geloso G1 1040 mods

Post by modman »


Last edited by modman on Mon Aug 13, 2018 3:54 pm, edited 2 times in total.
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roberto
Posts: 1841
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Location: Italy

Re: Geloso G1 1040 mods

Post by roberto »

Geloso are great amps that were very very common in Italy during the golden years.
Their price was reasonable and the quality and reliability was and still is simply superb.

Good to know that in Belgium the price is even better than in Italy.
modman
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Joined: Thu Sep 27, 2007 9:21 am
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Re: Geloso G1 1040 mods

Post by modman »


Last edited by modman on Mon Aug 13, 2018 3:55 pm, edited 3 times in total.
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roberto
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Re: Geloso G1 1040 mods

Post by roberto »

Let me check, I think I still have a Geloso tape recorder/player and a LP player somewhere.
Nice to know you studied the history of the brand.
andresound
Posts: 701
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Location: Durban South Africa

Re: Geloso G1 1040 mods

Post by andresound »

Pulling up a chair 👍
If it sounds good, it is good! Trust your ears
andresound
Posts: 701
Joined: Mon Dec 01, 2014 8:48 am
Location: Durban South Africa

Re: Geloso G1 1040 mods

Post by andresound »

Have recently acquired a G1.1110 with 4x EL503’s. Recapped it and fired it up stock. HUGE headroom, and well put together
If it sounds good, it is good! Trust your ears
modman
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Joined: Thu Sep 27, 2007 9:21 am
Location: Hoegaarden, BE
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Re: Geloso G1 1040 mods

Post by modman »


Last edited by modman on Mon Aug 13, 2018 3:56 pm, edited 2 times in total.
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roberto
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Re: Geloso G1 1040 mods

Post by roberto »

Modman, that's really interesting!
Can I ask you to open a thread with your documents?
modman
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Re: Geloso G1 1040 mods

Post by modman »

__
Last edited by modman on Sat Oct 20, 2018 9:58 am, edited 1 time in total.
modman
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Re: Geloso G1 1040 mods

Post by modman »

firticchio wrote: Tue Feb 11, 2014 10:04 pm hello everyone
I have a geloso g1 1040 50w that after few mods (preamp stage for guitar use and changed the exaust electrolitics) for functional test i would complete modifying.
the trasformers specs are
PT: 6v-6v 4A, 332v-332v 270mA, 39,2v-39,2v 150mA
OT: 4000ohm - 50-60w
choke: 3H
I already have 2 matched 6550, 2 matched kt88, several 12ax and 12au7, further the geloso original tube.
i attach the original amp scheme, the scheme with the mods i did for a test and the scheme with the idea for a 6550 mods (the power section need tweaks)
any advice for an amp whit this trasformers and with my ideas?
thank you and sorry for my bad english
hobbits wrote: Mon Mar 03, 2014 9:01 pm i'm a geloso 1040 owner also. Do you have a sound sample or video of the normal / bright section mod. you made?. Maybe i will do the same.
greetings Peter
I finally went this route, if it's anyting it's a Bassman/Marshall JMP50 --


lorebike
Posts: 1
Joined: Tue Jan 31, 2023 8:09 pm

Re: Geloso G1 1040 mods

Post by lorebike »

Buongiorno,
è possibile avere lo schema del Geloso 1040 con relative modifiche apportate ?
Grazie,

Good morning,
Is it possible to have the Geloso 1040 schematic with relative modifications?
Thank you,
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