Build Thread - A New Take on the Classic Pass Labs D1 with an ESS Dac

Well...

Or 32y0 if no deal with Pinnocchio.
FS: PCBs for ABBB, SSR03 and NTD1 (AUS)

BTW, anyone tried upgrading lower quality 200/400R resistors to the famous Riedon PFS35 180/390? Stuck home, wondering...

Can anyone get their hands on the Reidons? Back when I tried it seemed impossible. Given how simple the circuit is, it would seem that the resistor quality (noise) could make a real difference.
 
I tried contacting them some time ago to see how I could buy some but they had no production of those parts scheduled. Their only solution was to send me 2 pairs of samples.
Maybe if we can get a bigger order it would work? Although I doubt we would reach the minimum 500 of each required by DigiKey.
 
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Unfortunately I don't think the JFet matching from the link above can be used as it matches for Idss.
For the NTD1 we want to match for VDS and transconductance (Gm).

Owen posted the procedure to match the MOSFETs here: Post #672.

You basically need a lab PSU, a signal generator and DMMs. It takes a bit of time but it's not too complicated. If you have the above mentioned equipment, I would strongly encourage you to give it a try by following Owen's procedure.

Paul
 
Unfortunately I don't have the equipment to match them on my own right now and can't justify buying it for this specific purpose. I have emailed a few boutique audio parts stores that offer matched fets for other projects but no one has indicated they would match.

Does anyone here have a matched quad left over from earlier builds by chance?

I have all of the parts to complete the build other than the Reidons which I will try to track down - possibly from Reidon directly.

It sounds like the parts changes needed to allow the NTD1 to work with the 9038 were never finalized definitively. If it would just be resistor changes that's not a big deal...

After I think more about casing, I plan to try powering the NTD1 with a pair of Salas Ultrabibs which can deliver 38v.
 
NTD1 PCB

Hi Guys.

I am new here in the forum and only recently came up with the topic ntd1.
Now I am burning to build a dac with this i / v converter.
Of course I could build it p2p, but it would be better for me to realize it with the board from opc.
Unfortunately he does not answer my private message here via the forum.
I don't blame him, but I wonder if there might be an opportunity to get such a board.
If someone still has a circuit board, preferably with matched Fets, I would be happy to buy it.
Or is there a chance to get opc to have this board manufactured again?
I would be happy about any idea or recommendation.

Best regards, niels
 
I have the board with all parts sitting around except for the matched transistors and Riedons. My last email exchange with them quoted like $150 to get a few pairs of 180 and 390. At that price it would only take 4-5 ppl to get to the minimum order requirement if anyone is still interested…