Valve DAC from Linear Audio volume 13

I've previously declared that this DAC deserves to be built by more people and I've been reflecting on that. In light of that sentiment I have reconsidered and I am prepared to co-ordinate a group buy of another batch of PCBs for the DSD-only version of Marcel's design.

The deal will be;
  • DSD-only version of the PCB (PCB only).
  • Minimum order is 5 and then in multiples of 5.
  • Payment up front
  • Shipping and fees at cost (remember that I may incur customs charges that may increase the unit cost)

Please ask if you have any questions. I'm sure some clarification will be required depending on the level of interest.

There is some interest in a GB over on the Transcendent Audio - I will invite them to sign-up here.

If this is of interest copy and paste the list below and add your name (and qty).

Fred Scroggins - 1 PCB
 
Fingers-crossed that we get some more sign-ups.:xfingers:

Thinking positively, I think it will help you guys if I try and give you a steer on the potential costs of this build. Assuming five people join the group buy (say circa £80 per PCB), ignoring the upstream infrastructure to deliver DSD data to the DAC input (for which there are several options), without valves (again various cost options) but with perhaps a very cheap, basic chassis I think the project will cost at least £500 and likely a bit more - not cheap but,on the other hand, think what you're getting compared with commercial offerings. BTW, I haven't used boutique caps/resistors etc.

Within that cost esimate, apart from the main board, there is a non-trivial cost in the reconstruction filters. Marcel provided several different filter options; I'll find the post with the schematics later but for now here is a link showing my filters.

https://www.diyaudio.com/forums/dig...-linear-audio-volume-13-a-38.html#post6033155

As you can see I chose to use Lundahl LL1684 output transformers and the inductors are from Don Audio, custom wound and cost me about £100 for the four (Custom Inductor RM8 Core, 34,58 €). Obviously not the cheapest options but if you were hearing the music I'm listening to at the moment you probably wouldn't want to compromise. My filters are assembled on PCBs I desgned and I can make the gerber files available or supply a pair of the boards if they're of interest? (I designed them to mount in slots in my chassis but I can easily add some stand-off holes).

I've also got a copy of Marcel's BOM but with Mouser part numbers that should cover most of the main board components and will try to put together an indicative cost for them when I get time.
 
BOM - smd parts

Here's a link to load up a DigiKey basket with all the smd parts that I ordered for my build;

https://www.digikey.co.uk/short/z5whtb

and attached is a zip of the corresponding excel spreadsheet.

Cost of the smd parts is about £50 before taxes/delivery (should be free delivery anyway).

I'll do the same for the through hole parts when I get time.

Ray
 

Attachments

  • SDM Valve DAC - GB - smd BOM.zip
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