GM70 Amplifier with Tango or Bartolucci 845

Apr 22, 2009 at 3:24 PM Post #2 of 14
Is that schematic for one channel?

Tango NC20F is $805 and the X-10S is $1480 (shipped to the US)... not for the feint at heart. Looks VERY interesting, though...
 
Apr 23, 2009 at 5:30 PM Post #3 of 14
The power supply schematic will drive both the channels.

The amplifier section is relative to one channel.

The Batolucci transf. should be less expensive and these give a better sound.
 
Apr 23, 2009 at 7:04 PM Post #4 of 14
Ah... you had me at Lundahl (my Raven has 6 Lundahls)... so, guestimate at what the psu and amp channels can be built for?
 
Apr 24, 2009 at 1:36 AM Post #6 of 14
What do you estimate this amp can be built for? Looks like the copper plate GM70 will be about $100 each, but what do you estimate the other parts to cost? Do you have a BOM?

My Raven uses the Lundahl 1689, but I just couldn't (at the time) justify the amorphous cores (an extra $400), but see you suggest it here.

I am such a sucker for pricey iron and Russian tubes.
 
Apr 24, 2009 at 1:57 PM Post #7 of 14
The price for the 2 x Tango NC20F is $800 and for 2 x Tango X-10S is $1500 so the total for two channel is about 2300$.

The price for 2 x INT8C + 2 x 115BN is about 900 euro.

To add a good pair of power supply transformers (about 200 euro)

The tubes 200 euro

The capacitors 30 x 8 = 240 euro

The inductances 2 x 65 euro

About 1670 euro
 
Apr 26, 2009 at 3:31 AM Post #9 of 14
Ya mean like Frank Cooter's masterpiece here?

I'm thinking mercury vapor rectifiers also, and had been for a long time already.

My next project will be some combo of all this, once the (4) current amp projects are all completed, and sorted out (who stays, who goes). So, late year, or so.
 
Apr 26, 2009 at 4:26 AM Post #10 of 14
Well, I told myself that my next project (after the Pioneer fullrangers I'm working on) would be a nice Tripath class D amp to save power, money, etc...

But after those pics, I just gotta order up some big unreasonably expensive heavy iron for a boatanchor
frown.gif
 
Apr 26, 2009 at 10:01 AM Post #11 of 14
An amp like this doesn't have to cost a fortune if you're good at scrounging and can do your own casework. The GM70 amp I built came to about $1.500 in parts. The Stax amp I'm bringing to CanJam is very similar to the GM70 amp. Much higher gain, different output transformers, 813 outputs instead of GM70s, but same 1930s industrial design philosophy. Pabbi1, your absolutely right about the mercury rectifiers. No other rectifier comes close. By themselves, they're good for 15-20% improvement over any other type. Once you try this type of design you'll never be satisfied with consumer level designs again.
 
Apr 26, 2009 at 3:57 PM Post #12 of 14
Quote:

Originally Posted by FrankCooter /img/forum/go_quote.gif
Once you try this type of design you'll never be satisfied with consumer level designs again.


We can safely say that ship has sailed.
wink_face.gif


Can't wait to hear your designs at CJ...
 
Apr 26, 2009 at 4:58 PM Post #13 of 14
Where did you get your OPTs? That seems to be the biggest problem, as a 40W SE OPT good for 20hz is HUGE and not cheap...

The power supply is the other problem. Big caps good for 1500V aren't cheap either. I'm toying with the idea of super high voltage silicon...
 

Users who are viewing this thread

Back
Top