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GM 70 Schematic needed!

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i have two pairs of 6c33c monoblock on the way, but i will have an extra pair of boxes.... They are 45x27cm each so they are big enought to fit some GM70 SET.

Can someone recomand me a schematic? I will also need some building details for the OPT's as they will be custom wounded.

Thanks in advance!
 

Hello
I plant to build these amplifier.
Do you think I can use a 400mA 400-0-400V transformer?
I see in the schematic he use 500mA transformer.
I want to order my power transformer from Antec the best to feed these amp 2x360V or 2x400V both 400mA.
I think the 400V would be better if the power rating enough for a Stereo.
Please advise.:)
Thank you Gabor
 
Hello
I plant to build these amplifier.
Do you think I can use a 400mA 400-0-400V transformer?
I see in the schematic he use 500mA transformer.
I want to order my power transformer from Antec the best to feed these amp 2x360V or 2x400V both 400mA.
I think the 400V would be better if the power rating enough for a Stereo.
Please advise.:)
Thank you Gabor


You can use 400mA transformer, but with 400V you'll be close to 1000V dc. If your capacitors can stand it - why not, but you'll have to adjust R6 in power supply to get driver anode voltage right.
 
Hello
Thank you!
Yes I will adjust the needed resistors, I just wanted to know if the transformer can supply enough power for the two channel because 400mA not 500mA.
I have all the parts for the amp, just need the transformers. I do wanted to order a pair FIAT OPT but shipping to Canada 160Euros..
Also I want to purchase the power transformer but Antec has only these 400mA rating.
To order from Plitron a specially designed transformer it would cost $200-300..
Thanks one more time

Greetings Gabor
 
Here is what I am building.

Not on the schematic is the Rod Colman Heater boards for the GM70 filament heaters.
 

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I used an antek 400-400 500ma toride for my gm70 amp, choke input gave mw 670v with the gm70's drawing 120ma each and 45ma for the driver stage, which is mu follower with 6e5p at 22.5ma/180v/3.7Vgk.
fitting a few small value caps at the ps input got me to 800v.

i now have the antek 500-500v 400ma to give 900v with very little capacitence, i like to think of it as choke input with snubbing caps ;-)

hope that may be of helkp
enzo
 
I used an antek 400-400 500ma toride for my gm70 amp, choke input gave mw 670v with the gm70's drawing 120ma each and 45ma for the driver stage, which is mu follower with 6e5p at 22.5ma/180v/3.7Vgk.
fitting a few small value caps at the ps input got me to 800v.

i now have the antek 500-500v 400ma to give 900v with very little capacitence, i like to think of it as choke input with snubbing caps ;-)

hope that may be of helkp
enzo
Hello
Can you lead (i have the parts number) me to that transformer . I did look his stock and I only find 400mA.
Thank you very much
Greetings Gabor
 
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