1. Home
  2. digital
  3. 197786-194711

DIGITAL POPS WITH HDMI CABLE IN DDC TO DACS CONNECTION

Hello everyone.

I need your help. My setup is as follows: Lumin U1 Mini - USB - DDC Gustard U26 - I2S G to SMSL SU-X and I2S to Holo Cyan 2. I bought the U26 a couple of days ago and haven't been able to find an I2S cable, so I'm using a generic Chinese 8K/UHD HDMI cable, one meter long, while I wait for the Ricable I2S cables (SUPREME HDMI 2.0b MKII, 0.5 meters). I've already checked the connection compatibility and I think it's fine (IIS-G: Fixed Gustard standard protocol, IIS/SMSL SU-X Normal, and IIS: Gustard Mode 4, IIS/Holo Cyan 2). The problem is that the digital pops at the beginning of each track when there's a change in bitrate or format from PCM to DSD are unbearable. My question is: is this a result of using a cheap HDMI cable and will it be resolved with the Ricable I2S, or will it not be resolved...?
I look forward to your response.
Regards.

tutonunez
simonb
36 posts
 

First of all it might be hardware or software. You have quite a chain of devices between the source and the destination. The first step is to remove it and just test with USB.  If that fixes the problem you know where you are. If it's a software problem on the source where when it switches over then you can blame the Lumin. I have a bin full of cut up HDMI cables that don't make the grade. Usually intermittent faults. 

 

lanx0003
1,926 posts
 

Similar experience here but the issue is DAC specific. When I used u18 with micro dac it pops but not with d90 iii discrete. Don’t know why

 

tutonunez OP
19 posts
 

Simonb This problem didn’t occur with USB because, being asynchronous and buffered, both DACs eliminated it. So today I’ll look for a cheap but as short a cable as possible to experiment...

lanz0003 I hope this gets resolved because I won’t change the DACs, and I refuse to upsample and leave all the files at 176 or 192 kHz to avoid pops from frequency changes, because I don’t like how upsampling sounds on the Lumin. And honestly, the improvement with the DDC U26 was two or three levels higher (and it only has about 100 hours of use).

If there’s no solution, the improvement is worth accepting.

audphile1's avatar
audphile1
7,840 posts
 

The pops are due to your DAC handling bit rate changes. 
Are you using Lumin native software to stream? I don’t remember if it has a setting for a resync delay (don’t think it does). But I know Roon has it and it will in some cases completely eliminate the pop. 
Cables will not affect this. It’s your DAC. 

lanx0003
1,926 posts
 

Before concluding the dac is the fault, try bypassing ddC to see if the pops continues. The pop / static noise I was experiencing is not due to sample rate changing. When I connect streamer to dac directly the issue is gone. Also, when I used much cheaper ddC (smsl po100 pro) there is no issue with either DAC. I return u18 since. I maybe talk about completely different issue even the symptom is similar. 
 

btw I have not heard any reviewer reporting popping issue with SU-X due to sample rate changing. The issue was with lower end smsl dac. 

More to discover