On the Distortion of Cirrus Logic CS431xx-Based Devices: A Comparative Review

[MaxwellsEq]

By playing DSD (DoP), there are no problems at all.

Why?

 

[tccalvin]

Why?

It would make sense since DRE seems filter-related...

 

[MaxwellsEq]

It would make sense since DRE seems filter-related...

I've always assumed that the "NOS" removal of DRE was a design artefact. In theory the "Dynamic Range" aspect of DRE should be agnostic of input type, so towards the end of the logical functions. But I guess it just may not be in circuit for different paths through the DAC.

Thinking further, if DRE is designed to make a relatively meh core DAC measure better than it is on a standard test rig, perhaps it only needs to be switched on when measuring PCM at 44kHz, since that's the standard test case.

 

[CedarX]

I've always assumed that the "NOS" removal of DRE was a design artefact. In theory the "Dynamic Range" aspect of DRE should be agnostic of input type, so towards the end of the logical functions. But I guess it just may not be in circuit for different paths through the DAC.

Thinking further, if DRE is designed to make a relatively meh core DAC measure better than it is on a standard test rig, perhaps it only needs to be switched on when measuring PCM at 44kHz, since that's the standard test case.

Per CS431xx datasheet, NOS mode is minimizing internal digital processing. If it is the intent of that mode, also disabling DRE seems logical. But the datasheet gives no additional information (that I could find).

 

[KDRN]

just got the truthear keyx. and did the cmaj test. i didnt hear any crackling at all. it seems like ttgk/truthear disabled DRE by default or set it in such a low threshold much lower than the black pearl's. its pretty much inaudible.

 

[pangcukaipang]

just got the truthear keyx. and did the cmaj test. i didnt hear any crackling at all. it seems like ttgk/truthear disabled DRE by default or set it in such a low threshold much lower than the black pearl's. its pretty much inaudible.
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Nice, it's available for a while at the local store but I ended up buying 7hz 71 instead (nearly 50% cheaper). I wish I took the chance at this since it's so much simpler.

 

[fws]

Nice, it's available for a while at the local store but I ended up buying 7hz 71 instead (nearly 50% cheaper). I wish I took the chance at this since it's so much simpler.

It is not really a competitor to something based on CS43131 since it is 1Vrms dongle, but that is a nice price, I've paid $30 for 71 in 2022 (regular price was close to $40). Unfortunately I couldn't shake the feeling that the middle mids are boosted and it annoyed me so much I stopped using it (it worked perfectly for V shaped IEMs though) + it ran a bit too hot and sipped a bit too much battery for my liking. I apologize if I'm sounding like I'm trying to put a downer.

Some measurements, although for some reason I remembered SiNAD to be 104dB at 1Vrms, so maybe there were some other ones higher as well
https://www.audiosciencereview.com/.../jcally-ap7-and-7hz-01-usb-dongle-rmaa.38980/
Can't find it now, but there were pictures showing the same PCB in 71 and JCally AP7.