Soekris' DAC implementations

Sample Rate Swith "cracking" noise

Hello Folks,

not being sure if this is the right place to ask, so please be nice...

Just put an off the shelf Soekris DAC to work and actually enjoy this thing a lot!

There's on annoying thing, though:
I'm listening to Music in different resolutions from 16/44.1 and 16/48 to 24/88.2 and 24/96.
The Soekris does all that very well!
But when switching from one to another sample rate, there is this ear straining loud "crack!!" when the DAC switsches.

My question: Is there a "Muting while synchronising" possibility I have missed or is there a mod. or add-on I could use to mute the output until the "crack!" is over?

Thanks a bunch for suggestions!

Regards,
Winfried
 
First, make sure the DAC is running latest firmware. The sample rate locking noise has been nearly eliminated in the latest firmware.

The muting board will help with power on/off plops, but will not do anything for relocking noise by default. It is possible to build it to be controlled from the DAC, but in the current version of DAM1021 firmware the mute control line does not really work correctly.
 
Hi, i did ask this in a new thread. Missed this big thread so i better ask here..
I have a diyinhk usb card to the dam1021. But it can't lock the i2s signal and the dac is dead silent. The lock led flash on the dam.
Anyone know about this problem?
Regards //Daniel
 
1) Is the diyinhk usb card getting power from the USB port or does it need a separate PS? Are you powering it properly?

2) Are you powering the isolated side of the Soekris' isolator?

3) Are your I2S cables reasonable in length (less than ~10cm)?
 
1) Is the diyinhk usb card getting power from the USB port or does it need a separate PS? Are you powering it properly?

2) Are you powering the isolated side of the Soekris' isolator?

3) Are your I2S cables reasonable in length (less than ~10cm)?

1) it's from external PS and spot on 3.3v
2) the Sorkris isolator are powered with 3.3v at J3 pin 6 and 7
3) yes, the are standard 10cm cables.

Thank you for your reply. I have rechecked data, lrc and bck and the are in the right place.
Both the usb card and the Sorkris isolator take dc from same bridge but diffrent lm117..so same ground i guess. Can that have something to do with it?

Regards //Daniel
 
1) it's from external PS and spot on 3.3v
2) the Sorkris isolator are powered with 3.3v at J3 pin 6 and 7
3) yes, the are standard 10cm cables.

Thank you for your reply. I have rechecked data, lrc and bck and the are in the right place.
Both the usb card and the Sorkris isolator take dc from same bridge but diffrent lm117..so same ground i guess. Can that have something to do with it?

Regards //Daniel

Did you tie the usb card ground to the isolated ground of the dac? Or at least buzz them out to make sure they really are tied together?

Also, I was having trouble at first getting lock because I loaded in the wrong filter. Then I reloaded firmware, without loading another filter, and it worked fine for me.
 
Hi, i did ask this in a new thread. Missed this big thread so i better ask here..
I have a diyinhk usb card to the dam1021. But it can't lock the i2s signal and the dac is dead silent. The lock led flash on the dam.
Anyone know about this problem?
Regards //Daniel

Sorry - using an other USB interface so have no idea. Not using USB at all now actually.

//
 
Hello

Yes the GND from usb card goes to iso GND on dac card.
I did scope the data/sync lines from the usb card to the dac. They are there when playing music but the lock led just flash...

This is the input on the dac:
An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


I checked the 3,3v again to isolator on the dac card and that is fine.

Best regards//Daniel
 
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Is that diyinhk USB-i2s board the one with the 'bit-perfect volume control'? If so, it may be the culprit.

No it's the "standard" card.
To me it look like the usb card puting out a valid i2s signal.
BCK at 12,28 MHz, LRC at 192kHz and the datastream at around 2,8 MHz.
And that was at the input on the isolator ic on the dam1021.
And i have 3.3v connected to "feed" those isolator ic too.

Going crazy!! 🙁

Thank you all for your help.

Best Regards //Daniel