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tubehunter
15-03-2009, 14:48
This is my latest project, a CS4397 dac directly output to the double triode 6n3p dr coupled with Mundorf Supreme caps.
Its nice working with copper.

http://i514.photobucket.com/albums/t350/halx00/IMG_4200.jpg

http://i514.photobucket.com/albums/t350/halx00/IMG_4205.jpg

http://i514.photobucket.com/albums/t350/halx00/IMG_4204.jpg

http://i514.photobucket.com/albums/t350/halx00/IMG_4203.jpg

The case started out as 18 gauge copper sheet, cost me £75 for a 1000x500 piece.
The bottom plate is stainless steel 2mm thick and eats drill bits. The sides are solid Iroko hardwood, its a nice combination.



i'll add some internal shots later.

tubehunter
15-03-2009, 14:52
As promised some internal pix.
The CS4397 dac has been replaced with a TDA1543 X 4 in paralell with no over sampling, passive i/v.This suits the gain of valve stage much better giving enormous dymanics.
The CS4397 is very good but does have some glare, is this the internal i/v convertion inside the chip?internal op-amp?
This was my first attempt at point to point wiring and had to rip it all out twice before I managed to get total silence with the power amp at full gain.How you wire the earths are very important.
The sound can best be descibed as playing a record without a turntable but with non of the associated problems that brings.
The other copper case is the first order I have recieved so must be doing something right

http://i514.photobucket.com/albums/t350/halx00/IMG_4251.jpg

http://i514.photobucket.com/albums/t350/halx00/IMG_4252.jpg

http://i514.photobucket.com/albums/t350/halx00/IMG_4254.jpg

http://i514.photobucket.com/albums/t350/halx00/IMG_4255.jpg

http://i514.photobucket.com/albums/t350/halx00/IMG_4247.jpg

http://i514.photobucket.com/albums/t350/halx00/IMG_4249.jpg

http://i514.photobucket.com/albums/t350/halx00/IMG_4250.jpg

http://i514.photobucket.com/albums/t350/halx00/copperdacsimcopy.jpg

John
15-03-2009, 19:45
wow I bet it sounds as good as it looks

leo
15-03-2009, 20:02
Very nice:smoking:

Those TDA1543's are very capable, they sound much better than the spec would suggest

The CS4397 uses internal switching capacitors for the I/V, you also loose the lower noise if not using the differential output of the chip, mind you the TDA still probably gives a more analogue sound especially with the zero oversampling

tubehunter
19-03-2009, 12:21
If i'm building a nos valve/dac why not use some 1976 nos transformers. I found 9 of these transformers, hugely overspec but good quality. This time I've used brass with beech end cheeks, looks pretty good to me.

http://i514.photobucket.com/albums/t350/halx00/IMG_4257.jpg

http://i514.photobucket.com/albums/t350/halx00/IMG_4258.jpg

http://i514.photobucket.com/albums/t350/halx00/IMG_4260.jpg

Marco
19-03-2009, 12:28
I found 9 of these transformers, hugely overspec...


Haha, aye, you're not kidding - look at the size of the f*ckers! :lolsign:

How much does it weigh?

Love it. I do admire your design principles: 'if in doubt bigger is better'. Now where have I heard that before... :eyebrows:

Marco.

P.S Don't forget about my brass counterweight and acrylic PSU cover ;)

Ian Walker
26-03-2009, 19:11
Just got this up and runnin in my system,sittin here with a big daft grin on me face:)

Brassoboy.