Thank's for the link,
What driver is the best?
This uses 826
Greenvalve Audio 826 LC GM70 Tube Amp - YouTube
Regards
M. Gregg
What driver is the best?
This uses 826
Greenvalve Audio 826 LC GM70 Tube Amp - YouTube
Regards
M. Gregg
Looks good and not that difficult to build.
This one i use(see photo) with modified driver( now 6n6p).
Don't suppose you have a schematic?
Have you tried the 807?
Regards
M. Gregg
Looks good and not that difficult to build.
This one i use(see photo) with modified driver( now 6n6p).
NB its a nice build.
Is this your amp?
Regards
M. Gregg
For nice output transformer see link. Just send them a mail with what you need.
uitgangstrafo
uitgangstrafo
Hi M Gregg, I think 6e5p with Rods shunt cascode takes some beating driving GM70. Ale has a good write up of the topology here:
The Shunt Cascode Driver | Bartola Valves
There is also a lengthy thread here about it somewhere.
I use a pair of 6K to 8R output trannys. They were a bargain unknown from eBay that seem to be custom Audio Note jobs. Measure very well and are heavy as @#$%. HT is 1KV.
Don't have a schematic at the mo as it's still on the breadboard. I can scribble down what it is now if you need but it ain't pretty
Cheers
Matt.
The Shunt Cascode Driver | Bartola Valves
There is also a lengthy thread here about it somewhere.
I use a pair of 6K to 8R output trannys. They were a bargain unknown from eBay that seem to be custom Audio Note jobs. Measure very well and are heavy as @#$%. HT is 1KV.
Don't have a schematic at the mo as it's still on the breadboard. I can scribble down what it is now if you need but it ain't pretty
Cheers
Matt.
I shall tomorrow look for the schematic.
The transformers came with the chinese amp. This amp was cheaper complete then building yourself. About €400,-. Just did some modifications.
Current building a GU81m amp wih the FU13 as driver.
Ok thank's,
I have an itch if you know what I mean..
Regards
M. Gregg
Hi M Gregg, I think 6e5p with Rods shunt cascode takes some beating driving GM70. Ale has a good write up of the topology here:
The Shunt Cascode Driver | Bartola Valves
There is also a lengthy thread here about it somewhere.
I use a pair of 6K to 8R output trannys. They were a bargain unknown from eBay that seem to be custom Audio Note jobs. Measure very well and are heavy as @#$%. HT is 1KV.
Don't have a schematic at the mo as it's still on the breadboard. I can scribble down what it is now if you need but it ain't pretty
Cheers
Matt.
Yes the output Tx's are an issue.
But if SY is correct they ain't gotta be silver..LOL
NB nice to hear from you matt..
But can you beat an Ongaku..
But what about the 807 as a driver?
Regards
M. Gregg
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Good to hear from you too
Certainly don't need silver in your transformers or anything at audio frequencies imo. Lol.
Not sure about beating an Ongaku, never heard one. I'm sure my speakers and ears are not good enough
I thought about 5B255M (807) to drive mine as they look very nice next to a GM70. In triode I'm sure they would be fine but you would need either 3 stages or a rather high output pre amp. I prefer two stages and just a volume control if I can get away with it without too many compromises.
Of course it would also be possible to use Rods circuit and another DHT. That would be excellent.
As you can see I don't mind some sand in the signal path. YMMV
Cheers
Matt.
Certainly don't need silver in your transformers or anything at audio frequencies imo. Lol.
Not sure about beating an Ongaku, never heard one. I'm sure my speakers and ears are not good enough
I thought about 5B255M (807) to drive mine as they look very nice next to a GM70. In triode I'm sure they would be fine but you would need either 3 stages or a rather high output pre amp. I prefer two stages and just a volume control if I can get away with it without too many compromises.
Of course it would also be possible to use Rods circuit and another DHT. That would be excellent.
As you can see I don't mind some sand in the signal path. YMMV
Cheers
Matt.
How about Hammond 1629SEA? Look a good fit to me.
Anyone have any experience of them?
Cheers
Matt.
How do they compare with Edcor frequency response?
Regards
M. Gregg
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