AN DAC 2.1

I was looking to get a more 'analogue' sound out of my existing system (Cyrus CD8, Audio Research LS16 preamp, Welborne Labs* Terraplane mono blocks into Tannoy Stirling Speakers) and decided to take the plunge and build an Audio Note Signature DAC 2.1 after reading a number of reviews indicating it's capable of producing the results I'm looking for.

This page will show a few stages of the build but not in any great detail. Paul Brookes has already produced an excellent page which has been invaluable when deciding on which DAC to buy and during the build itself. However, the DAC has evolved a little since Paul's build;

• The digital and analogue supplies are now derived from a common transformer
• The digital PSU board is a new design
• Twisted pair cables have now been supplied for all AC supplies
• The hard-wired analogue board has now been dropped

This page may be of use to anyone building the late version.

* Please don't interpret my use of Welborne Labs amplifiers as any form of endorsement. I had a number of problems in my dealings with them and won't be going back...

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After a number of emails with hifi collective, I placed the order and received the kit a few days later. There were a few items missing but these had been identified earlier in an email and are expected shortly. All of my questions with hifi collective have been answered quickly and I would have no hesitation in recommending them to anyone else and will probably be returning to them in the near future for a Glasshouse passive preamp.

The first photo shows the results of the first evening's work, mounting the transformer, choke and connecting them to the IEC connector.

Note: I have opted to mount the IEC connector with the earth pin uppermost. The live and neutral wire have therefore been transposed on the rear of the connector to keep the fuse on the live rail. top

I like to keep wiring neat so used a slightly revised construction sequence that would permit me to lace cables into looms between boards. (If anyone's interested a guide to lacing may be found here.) The supply board was built in accordance with the manual and cables laced to the transformer. I've included the connection to the digital board in the same bundle.

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The digital boards (supply and DAC) were built in accordance with the instruction manual. The only change I made was to use some Van Den Hul coax for the digital connections. This has been used for both the S/PDIF and USB inputs. I prefer the construction of the Van Den Hul cable which incorporates a foil shield as opposed to the single braided version supplied.

The ground connection at the PCB end is rather small so I terminated the outer using a technique borrowed from the grounding of mil/control cables;

Tease out the braid into single strands using a plastic pointer then twist to form a single ground conductor cable.

Bend the outer back on itself and tin with a little solder. Solder a short length of cable to the tinned end.

Finish off with a piece of heatshrink to keep things tidy and provide a degree of mechanical stability.

The photo above shows the finished cable attached to the board.

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There's very little to say about the rest of the build - I simply followed the well written instructions. The only problem I had was that the mains fuse blew when I first powered on This was traced to me fitting the wrong type of valve (a 6SH7 had been supplied with the kit instead of a 6X5 rectifier). I should have been more careful when checking off the parts when they arrived...

Brian of Audio Note Kits couriered me out a replacement tube as soon as I alerted him to the problem and even included a couple of spares.

The only modification I made was to fabricate a screen to partition the AC power and audio sections. I've not made any comparisons between performance with/without the screen so can't say if it's required or makes any difference to the performance of the unit - it just seemed like a good idea at the time.

I also fitted a Response Audio wooden fascia (supplied via hifi collective) to the unit. I personally feel that this is a huge improvement over the standard glossy panel.

It's early days with the DAC just yet but initial thoughts are very favourable. Needless to say, it does sound different (but not by much) to the onboard DAC on my Cyrus CD player. It's not quite so 'forward' and is ideally suited to the acoustic blues that I spend most of my listening time with. I'm always a little sceptical of reviews concluding that 'another veil has been removed' and claiming blacks inkier than the inside of an octopus so you won't find a lengthy review here...

Of interest to the kit builder is the quality of components and support; Both are absolutely first rate and I would have no hesitation in recommending this kit to anyone else. The only slight snag I found is that the rear panel has cutouts for the power switch that were used for the second transformer on earlier models - I'm looking for a suitable grommet to seal the hole.

Overall though, it's good fun to build and is very easy on the ears... Isn't that what it's all about? Ten out of Ten.