Copper Dac

[tubehunter]

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.









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]

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

[John]

wow I bet it sounds as good as it looks

[leo]

Very nice

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]

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.

[Marco]

I found 9 of these transformers, hugely overspec...

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

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...

Marco.

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

[Ian Walker]

Just got this up and runnin in my system,sittin here with a big daft grin on me face

Brassoboy.