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#46 Re: GM70 Monoblocks’

Posted: Sat Mar 30, 2024 11:43 am
by Paul Barker
The news update is I miscounted Anode chokes. There are 3 per channel. No need to worry, I think I have enough.

#47 Re: GM70 Monoblocks’

Posted: Sat Mar 30, 2024 1:00 pm
by Paul Barker
Homemade kathode caps


#48 Re: GM70 Monoblocks’

Posted: Sun Mar 31, 2024 6:58 am
by Paul Barker
I found a wooden thing in £ shop yesterday. My caps haven't arrived. But it appears I shall have to put as many as I can fit standing tall on top, because they arent the best thing to put inside as their volume is great and the amp case isn’t spacious, I have anther power choke two filament transformers and 6 anode chokes power resistors and a whole load of point to point wiring to fit beneath.

Valve bases on order, capacitors on order, I think I have enough resistors, the white coffins take up space. The el84 resistors are ok to mount against side thick aluminium side panel. Trying to make the new stainless steel when it arives to not look like a pin cushion. Thinking of Arulditing the ceramic bases up from beneath.

Havent thought yet how to stand capacitors neatly. But just came to me. Araldite.

When I was a young boy my friends Dad an action man in the war, was building a cannoo with araldite. He said “this is a good glue Paul, they build bridges with it.”

When Delta forse failed to rescue US hostages from Iran, the SAS were asked if they were involved. To which the short reply came “if we had been involved it wouldn’t have failed”. Where is this going?

“If araldite was involved building that US bridge, it wouldn’t have failed.”

Plans patience period. Carefully planning avoids piss poor performance.

#49 Re: GM70 Monoblocks’

Posted: Sun Mar 31, 2024 7:36 am
by Paul Barker
My careful planning has got me thinking about valves. We like to see them on top, we are like male peakocks.

Im not saing yay or nay. But when all caps are here, I shall see how the extrenally mounted components goes. Amaybe all the caps fit above, all remaining chokes and transformers fit above. Maybe there is room for valves. But they are the last thing to need it. Theu could live on the mezanine floor a neatly punched and grated hole above each valve. If there is space for said grated hole. There may not be, which wont matter at all. They can all sit upside down in the basement, so as removal of base panel to tube roll. A slow running fan powerd with the filaments wont be heard keeping the EL84’s alive longer. Its an EL84 thaing. They overheat.

I might letracett in Gold on the black blank front. EL84 Thaing.

#50 Re: GM70 Monoblocks’

Posted: Sun Mar 31, 2024 8:38 am
by Paul Barker
Its not going to be easy. The tin caps arent whats going in. The plastic ones are smaller diameter.





But it may be possible,

#51 Re: GM70 Monoblocks’

Posted: Sun Mar 31, 2024 11:28 am
by Paul Barker
I’ll start new plans to go off board with the power supply. This chassis is too small and the power supply is so important I can’t compromise with it. Actually the rediculous thing is the 630v capable power supply Im using with the EL34 stand alone amplifier would become surplus when the GM70 amp is built. This power supply will fuel anything up to 630v b+.

So now I can focus on the signal section to drive the future GM70 signal section and the GM70 power supply.

This existing power supply stands a loan for everything else. I can only listen to one signal stage at a time.

#52 Re: GM70 Monoblocks’

Posted: Mon Apr 01, 2024 9:57 am
by Paul Barker
Right, so as this driver amplifier shall complement the GM70 putput stage I shall tailer a power supply for it, butit it cant fit this chassis without compromise and difficulties.

This is where you end up requiring a lot of floor space. Ive been here often. It would probably fit a likewise dimension chassis as the signal section. So would look neater if that were so.

Perhaps I’ll first check cheap chassis on Ebay.


Close enough the signal chassis is 360 X 270 area. So they can fit one on top of another.

#53 Re: GM70 Monoblocks’

Posted: Mon Apr 01, 2024 10:38 am
by Max N
If you haven’t ordered that Hammond chassis yet…

How many of the Nightingale chassis do you have?
You could order some blank aluminium plates cut to size to fit those? Plus maybe a few spares?

#54 Re: GM70 Monoblocks’

Posted: Mon Apr 01, 2024 10:43 am
by rowuk
When I see builds like this, it reminds me of the late 1970s and early 1980s with those magnificent huge receivers from Kenwood, Pioneer and Sansui. They were not just big boxes, they were full.
s-l1600.jpg (208.34 KiB) Viewed 339 times
My opinion is that a "magnificent" build like this should also get a big, statement box so that the components have room to breathe, the coils, chokes and transformers have adequate space to spread their magnetism without interfering with one another. Maybe a tribute to the time when automobiles and hifi did not need to be practical.

#55 Re: GM70 Monoblocks’

Posted: Mon Apr 01, 2024 4:41 pm
by Paul Barker
I ordered it already. I have another Nightingale, not used but kept in manshed so would need a brush up with fine wire wool.

But the GM70 output monoblocks will need half width chassis, and probably same dimensions for power section. So I could buy 4 same chassis. The power supplies would have big power transformers and same size chokes and a pair of U19 each and a single 572b each.

I wont get it all on the bus.