BUILD THREAD - A New Take on the Classic Pass Labs D1 with an ESS Dac

[opc]

Hi bigpandahk,

Any transformer intended for digital signals will be all right as long as it fits. There are several threads on here dedicated to some favourites.

If you're not using the XLR input, then I wouldn't even both with it. I still don't have mine populated.

As for the package size, Hochopeper is correct, it's by far the most important things to match up. Do your best to match the size, value and voltage, and if possible the dielectric type as well. Most respectable retailers will have dozens of caps that match.

Regards,
Owen

[bigpandahk]

Originally Posted by opc

Hi bigpandahk,
As for the package size, Hochopeper is correct, it's by far the most important things to match up. Do your best to match the size, value and voltage, and if possible the dielectric type as well. Most respectable retailers will have dozens of caps that match.

Regards,
Owen

Thanks Owen, actually, I already followed your latest BOM to order all the components from Digi-key today. Now the only missing parts are the PCB+FET, trimmers and power transformer. Of course chassis and heatsink are difficult items to choose.

[bigpandahk]

Hi Owen

What mains transformer are you using? I can't find such high voltage small current transformer (40V x 2 150mA). Do I have to custom made one?

[opc]

Nope! I use these:

Antek - Transformers - Grid View[]=0

Cheers,
Owen

[bigpandahk]

Thanks Owen, I shouldn't have asked this silly question as you have mentioned it in post #20. The Antek transformers is cheaper than those I bought in China. The shipping cost is more than the three transformers for the NTD1. Trying to think of any more required to fill in the packing to save some shipping cost :-)

[pedefede]

Since the groupbuy is soon finished, we might discuss parts

Previously people adviced Murata, TDK for the decoupling caps:
2,2uF 50V+
10uF 10V

I found these:
GRM32ER72A225KA35L Murata | Mouser

C3216X7R1A106K TDK | Mouser

They seem ok'ish. Is there anything better?
(I did order zfoil resistors, so I want the best SMD there is for the job (if such a thing exists).

[qusp]

when are people going to realize that for small signal decoupling, SMD outperforms any leaded part.

look at the BOM, opc doesnt choose bad parts. what are you judging them as only OK'ish by? price? what positions did you order Zfoil for and what Zfoil part did you choose?

the murata are fine

[opc]

Originally Posted by qusp

when are people going to realize that for small signal decoupling, SMD outperforms any leaded part.

look at the BOM, opc doesnt choose bad parts. what are you judging them as only OK'ish by? price? what positions did you order Zfoil for and what Zfoil part did you choose?

the murata are fine

Agreed... people just aren't okay with the fact that:

a) Most SMD parts are not very expensive.
b) There aren't really SMD parts that have the words "Super" or "For Audio" printed on the side.
c) People somehow think that a large cap is a better cap.

What people seem to ignore is that SMD parts have a massive advantage in that they have no leads, and therefore not lead inductance or resistance. They also allow for better layout, which means shorter PCB traces which again reduces parasitic inductance and resistance and improves decoupling.

You absolutely could not achieve the level or performance these designs have if you used "Audiophile" PTH parts everywhere.

Save those giant audiophile parts for signal path and AC coupling applications where the lead inductance and resistance doesn't matter as much, and they have less of an impact on layout.

Cheers,
Owen

[pedefede]

ok, you guys get me wrong:

Originally Posted by pedefede

so I want the best SMD there is for the job (if such a thing exists).

I DO want smd-caps. I DO know they are good. I do not want big pulky filmcaps here.

What i asked for, was WHICH smd-coupling cap would be the best, for this task.

(I couldnt find a good discussion, about different types, or brands (in the same way that you can for through-hole-caps). So i kinda hope for one. After all, there are quite some different types/brands of MLCC out there ...

[qusp]

sorry calling them ok-ish and 'if such a thing exists' doesnt put that across, but maybe thats just English not coming across as intended. I guess opc and I assumed you had looked at the BOM? first page of this thread has the bom from the last GB, most part assignments will be the same, or at least give you the right range. the TDK and murata X7R and np0/c0g are preferred. these are decoupling caps though, so uber tight tolerance, or amazing tempco are not a big deal

which zfoils did you get and for where? the tx220Z for the power resistors are really the only resistors in the direct signal path, thats what i'm using, I just hope you havent bought zfoils for other positions needlessly. even those positions are not really necessary, but if you are going to tweak, those and the output caps are really the only positions.

opc wouldnt even buy zfoils if it was up to him, myself and the last GB sent him some as a thankyou