DDDAC 1543 MKII distortion on analog output

[zdr]

I just completed DDDAC 1543 MKII and I have a problem at the output - something is riding base harmonics, and sound is pretty shi**y. While waiting for response from Doede, thought someone might seen this before or have an idea where to look. Boards are supplied with 11V LM317 stabilized, 120VA toroid.

I am feeding it with SPDIF from SB live and CD4000. FS looks quite good on the scope. I tend to suspect TDA1543 tower.

[dddac]

hi,

i saw your mal. but i am traveling and for some reason cannot send mail from the hotel network

any way, we can take this off line when I am back next week. Two questions already, have you put the sound card on 44.1 kHz and 16 bit? any thing else will not work fine

have you tried a "normal" cd player to the spdif input?

regards
doede

[zdr]

Hi Doede,

Did some more testing. Sound from SPDIF out of Marantz CD4000 is much better. However, when I put test CD with 1kHz sine wave, I hear low freq "clicks", around 1Hz, even from CD player. I did not catch that on the scope. Same signal/CD plays clean from CD4000's analog output.

I am using the same sound card settings which I used for DiyEden SVDAC without problems. I will doublecheck them.

The signal riding sine wave is too high, around 50KHz so that is not what I heard Not present in CD4000 DAC though, but that is probably not my problem.

[zdr]

Output format: 44100 Hz, 16 bits per sample, 2 channels
Active buffer size: 2000 ms (352800 bytes)
Device: "02: SB Live! Audio [9400]"
Mixing: hardware, primary buffer: inactive

Buffer playback cursor: 16444 bytes
[===#============================================== ==============]
Buffer write cursor: 334800 bytes
[================================================== ===========#==]

Data buffered:
Total: 1995 ms (351908 bytes)
Async buffer: 190 ms (33552 bytes)

Buffer locks done: 536
Underruns: 0
Time played: 1:06.093 (11658844 bytes)
Time written: 1:08.088 (12010752 bytes)
Total time played: 2d 4:38:17.673
Volume: 0.000000 dB / 0.000000 dB

[dddac]

Things seems to fall in place. This theme has been around here a few more times before already. If you "listen" to pure sinewaves with NOS, A-Synchrone reclocked dacs, you will have clicks on a frequency which is the difference between the source clock and the reclocking clock. No way around it.

Listening to music (what most of us do) this effect is not noticable and interestingly enough (that is why it is done) produces more detailed soundstage and more spatial sound than with no reclocking (cs8414 is synchrone with source clock with build in pll)

[zdr]

Ok, I can live with that. But more serious issue is with PC as a source. Sound is quite distorted. When singer pronounces "S" it sounds like "F". Tried from two PCs already, SB Live and SoundMax. Both play perfect through Diyeden DAC. I can hear pops and clicks even with nothing playing.

[Cobra2]

Most soundcards put out resampled digital signal, at 48kHz.

Try without the clock on Dac.

Arne K

[zdr]

That might just be the case. I tried to google my way to 44.1 KHz and there seems to be no solution, at least I could not find one. Asio4all does nothing so it seems. Am I stuck with the DAC I cannot use at all?

[zdr]

I kinda don't get it. Is this a normal spectrum of a 15KHz sine wave for NOS DAC or do I have a faulty one? This from CD transport SPDIF.

[zdr]

Now that I know what to listen to, clicks are audible for sure. I find it difficult to accept it as normal.

TITLE "Colour of the moon"
PERFORMER "Allan Taylor"

Song starts with high freq bell and it's full of clicks, same ones from sine wave.