A nice dac to complement the Aleph-X.

[SvErD]

I'm also intrested, but I don't mind waiting a couple of months and get a debugged version.
You do great work Peter.

[kasra]

The 1541 has 0 to -4 mA out, is it possbile to use it in dual differential mode with the analogstage of pass D1?

/kasra

[uli]

Originally posted by pquadrat

Feedback on this design is welcome, maybe I will do a second version later this Year. With error corrections and improvements, but basically the same concept.

-Peter

Thanks Peter,

looks gorgeous!
detailed fb you will get after assembling & testing.

Now I gote trouble to get AD1896.

BTW for what reason is that AD?
Is it an improvement to send only 96/24 to DF1706?
This filter eats everything I thougt?

Uli

[peranders]

pquadrat, nice work

Is the pcb two layer or more?

I myself will update my DAC project but this is the future....sometime. The current CS4328 DAC is working very well but it would be cool to have the latest technology.

[pquadrat]

Originally posted by peranders
pquadrat, nice work

Is the pcb two layer or more?

I myself will update my DAC project but this is the future....sometime. The current CS4328 DAC is working very well but it would be cool to have the latest technology.

It's only two-sided. And only about 20 vias. I will try to make an improved version later this year, no time at the moment, and I would incorporate feedback from the users of this PCB version.

Abot the 1.2mA output current of the PCM1704: earlier in this thread are changed values for some resistors. If I remeber right, there are the values for 2mA output in the parts list. But I run my own DAC with these, and the output voltage is only slightly lower than normal. So You can try both.

And please post if You got it running !

-peter

[peranders]

Why have you chosen a relay for your digital input? Why not connect via a mux or a simple gate?

Have you considered to upgrade your DAC to "monster" PCM1792?

Don't you get rather much DC offset from yoour output stage?

Why do you have so odd values of some parts, 8.2 µF for instance?

[uli]

Originally posted by peranders
?

Have you considered to upgrade your DAC to "monster" PCM1792?

Don't you get rather much DC offset from yoour output stage?

Hi Peranders,
sure PCM1792?
There is nothing on TI´s page. As far as I know is
the PCM 1704 by far the best TI converter.

The Dc offset will be handled by the outputcaps
in peters design, in my version (which I am building
now with Peters board - thanks Peter) there is a
slightly different circuit, which doesnt need the caps.

Uli

[Sparhawk]

Originally posted by uli

The Dc offset will be handled by the outputcaps
in peters design, in my version (which I am building now with Peters board - thanks Peter) there is a slightly different circuit, which doesnt need the caps.

Uli

Is your circuit still based on the Pass D1, with modifications to eliminate the output caps? I'd be interested to see the circuit, since I bought one of Peter's boards.

[uli]

Hi sparhawk,

The circuit is shown on first or 2nd page of this thread.
I´m working on X-ing it now, I´ll post it asap.

Uli

[grataku]

As you guys know, the 7 boards that Peter printed out are long gone. However, he seems to be prone to doing a re-print in a short period of time if someone is willing to do the money collection and shipping.
As you can see there is another upsampler available or the AD1895 could be used instead. Some supposed minor bugs will be fixed, too. If there is enough interest I could handle the payment and distribution in the US, someone else would have to do Europe because it wouldn't make sense to have boards cross the atlantic ocean twice.
Please send me an email if you are interested.

Here is the letter he asked me to post:

Hello,

about the AD1896: Yes, it is out of production, but has been replaced
by the AD1896A. Same device, same specs, but minor bug fix. I got two
samples from Analog on request. Just to email the right people.
And if You have problems getting the 1896A, You can use the 1895,
which is available from AD's Web site as a sample, and is pin
compatible.
Just a little lower specifications. I assume the FIR filtering uses
less
prcision.

Yes, I can do a little rework of the board, not for an different
upsample,
as written above, but to fix some minor bugs (as written in the
forum).
If someone handles the individual shipping, I could even order the
boards from
the same manufacturer than the first run. Quality was very nice.
Its only the problem that I do not have time to handle all the
shipping
and payment work/trouble.

But I would like to get feedback from some of the seven buyers
on this board, to see if there is something to improve. Not the
"ususal"
hints of some members of the forum, but real fixes and improvements.

You can post this mail on the forum, I am very limited in time this
month.

Regads,
Peter