Valve Output DAC Designed by Nick Gorham

[Ali Tait]

Thought I'd post something about this new DAC I've acquired.
This came about via a beer-fuelled discussion at the last Owston meet, where Nick had brought along one of the dac boards with a couple of trannies to run it. The board is one of these-

http://www.ebay.co.uk/itm/NEW-Hi-end...item2c5cfad4f6

Don't be put off by the low price, this is a serious DAC, and is used in the Logitech Transporter amongst others. It has been called a "Miracle" DAC, a true 24 bit 192kHz chip, and is DSD capable. It has a virtually flat noise floor all the way up to 80kHz.

Anyhow, when I heard the board at Owston, I was struck by how good it sounded (the board is self contained and includes an opamp output stage. The opamp is socketed, so easily swapped out) and I mentioned to Nick how good it might sound with one of his valve output stages on the end.

A good few beers later, I offered to bankroll the valved dac to see how it sounded, reasoning that if I didn't like it, it would be easy to swap the dac board for something else. I already knew how good Nick's output stage was.

The upshot is what you see below-











The DAC is single input at the moment, though Nick has said adding switcheable inputs is no problem. It also has balanced outputs, useful as I intend to go that way with the direct coupled electrostatic amps.

So how does it sound? Bloody good IMHO! Bags of air, space and detail, but the usual digital glare is totally absent to my ears. It's an overused term, but this really does sound analogue.

It way outclasses my AN Dac Zero, and I always thought that was a very good DAC.

There is a marathon thread on this board on diy audio-

http://www.diyaudio.com/forums/digit...93-5532-a.html

I have ordered an unpopulated board in order to try a board with all boutique components as detailed within the thread. It'll be easy to swap over, so easy to see if I've wasted my money! Be fun trying it out though.

[Ali Tait]

PS, sorry about the crap photos, my phone camera is rubbish.

[Covenant]

Wow, a serious piece of kit. Why three trannies?

[Ali Tait]

You mean the toroids? Two for the dac board, and one for the valves.

[lurcher]

There are two off the shelf toroids for the DAC and one custom one for the valve stage (B+ and heater). The three EI transformers are one choke for the B+ and the two Sowter output TX's.

[Marco]

Awesome, Nick. I'd like to hear that sometime! What are those fat mothafukka cables connecting the two boards?

I don't think I've ever seen cables so thick being used internally inside equipment!!

Marco.

[Ali Tait]

Dat's the signal cables from DAC board to Valve grid.

I'd like to put this up against your Sony sometime Marco.

[Reid Malenfant]

I may be wrong, but it looks like balanced shark cable which is available from Maplin. For the money it's superb stuff if so... By the way, in reality the stuff isn't as blue as it appears on the Maplin pic

Apologies if i'm out by a country mile

[Ali Tait]

'Tis this I believe-

http://www.hificollective.co.uk/cata...mk8monvgphb5a6

[lurcher]

It may well be Shark, Its whats left over from when I built the 211 and the first balanced cable I put my hands on :-)