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

[Somafunk]

 

[NTK]

This is an awesome thread. But would you mind updating the leading post to with the full name of whatever DRE is an acronym for as part of the very first use?

For example: [7/23/25] ... disabling Department of Real Estate* (DRE) on the ...

* When I do a google search on DRE, that is the only meaningful definition that was returned (along with references to Dr. Dre). But somehow, I suspect DRE in this context means something different than California's Department of Real Estate.
Edit: As a general convention, the full name should always be provided the first time an acronym is used. I realize that it is defined in the text further down the body, but it would be useful to add the definition for people who come across the thread and just read the very valuable change log to get a sense of the overall post.

May be you should read at least a few sentences into the actual contents of the first post, not the change log, before complaining? The three-letter acronym is clearly explained in the introduction.

 

[IsaacOscar]

I ran the tests and the Tempotec Sonata BHD Pro and the iBasso DC07 PRO have this issue. The FiiO KA11 (which should be Cirrus) doesn’t seem to have this problem. On all of these devices, it’s impossibile to disable the DRE

Can you post some measurements (a spectrogram recording of you playing the major test file?)

 

[Sebby]

Can you post some measurements (a spectrogram recording of you playing the major test file?)

At the moment I don’t have the equipment to properly test it. I’ve always trusted Amir and I’ll continue to do so. I’ll simply avoid looking at Cirrus from now on. The tests I’ve done are "subjective", as I already said.
On all my Cirrus devices the issue is very easy to hear and I’ve always heard it, but I used to blame 5G interference from the smartphone.
For example, the KA11 is very prone to that when I’m sending messages and the Topping G5 as well when I place the smartphone on top of it and start streaming a track.

Anyway, while I’m writing this, I’ve put on the IE200 and connected the KA11 to the smartphone. I have to correct what I said earlier, because the issue is also audible on the KA11, but much more mildly and only on a couple of tracks. I really have to concentrate hard to hear it and only because I know exactly where it appears and what happens, otherwise I probably wouldn’t notice it.
As disappointed as I am, considering the price and its very clean driving power, aside from those very slight issues, I still wouldn’t have a problem recommending the KA11

 

[IsaacOscar]

At the moment I don’t have the equipment to properly test it.

I've simply used a cable from a 3.5mm output to my computers line-in port (a mic port will likely also work). And that was more than enough to record the distortion.

On all my Cirrus devices the issue is very easy to hear and I’ve always heard it, but I used to blame 5G interference from the smartphone.

Really? What were you listening to?

For example, the KA11 is very prone to that when I’m sending messages and the Topping G5 as well when I place the smartphone on top of it and start streaming a track.

Didn't you say the KA11 doesn't have the problem?

As disappointed as I am, considering the price and its very clean driving power, aside from those very slight issues, I still wouldn’t have a problem recommending the KA11

For about the same price, you can get the Fiio Tiny, which has more features (e.g. PEQ and a charging port) and no cirrus chip (sadly it's got a bug of its own, but that only occurs when using certain PEQ features).
(there's also the JA11 and Jeizi, which also have PEQ if you are cheap)
Sadly none of them have bean measured by Amir yet, so maybe they do perform worse.

 

[Sebby]

I've simply used a cable from a 3.5mm output to my computers line-in port (a mic port will likely also work). And that was more than enough to record the distortion.

Really? What were you listening to?

Didn't you say the KA11 doesn't have the problem?


For about the same price, you can get the Fiio Tiny, which has more features (e.g. PEQ and a charging port) and no cirrus chip (sadly it's got a bug of its own, but that only occurs when using certain PEQ features).
(there's also the JA11 and Jeizi, which also have PEQ if you are cheap)
Sadly none of them have bean measured by Amir yet, so maybe they do perform worse.

As for the KA11, and as I mentioned a few comments above, I noticed that it can be heard too, although very, very weakly, and only on one track.
So, as already stated, the KA11 has no problems and can be considered reliable. In fact, I will continue to use it as I always have, unlike the others, which clearly have this problem that emerges on very dynamic tracks during the quietest moments, but with almost no background noise even when the volume is pushed to the max in those instances.
There aren’t many tracks like this, but they do exist...

I tried measuring the KA11 through the microphone input, and honestly I don’t trust it much, but it was clean enough to at least see the upper part of the bump if it were present. However, it doesn’t seem to be there and I repeat that I really don’t trust it much. I should probably buy an ADC from E1DA and keep it in a drawer

Seeing that some manufacturers have fixed this through a software update, I think the issue can be dismissed by learning to choose Cirrus DACs that at least have the option to disable DRE, or DACs from another manufacturer.
The Sonata BHD PRO has a 3.5mm port that no longer works so I will be using the KA11 for a long time. Otherwise, the BTR17 will be more than sufficient for any listening done away from the desk and that’s fine.

I just hope that other measurements from other Cirrus manufacturers will come out, at least for intellectual honesty

 

[confucius_zero]

I think the issue can be dismissed by learning to choose Cirrus DACs that at least have the option to disable DRE, or DACs from another manufacturer.
...
Otherwise, the BTR17 will be more than sufficient for any listening done away from the desk and that’s fine.

Story of my life (I also own the BTR17 and love it), but at the very least the cheap RetroNano, Melody and BlackPearl have the DRE-Off option

 

[IsaacOscar]

There aren’t many tracks like this, but they do exist...

I understand if you're too shy to share (I'm very worried about people judging my music taste as I don't listen to the really popular artists...)! I was curious because I've never noticed an issue after years of using a humpy DAC, and I haven't found anyone mention any specific pieces of music with the problem other than the Song of the sisters (by Hanz Zimmer).

I tried measuring the KA11 through the microphone input, and honestly I don’t trust it much, but it was clean enough to at least see the upper part of the bump if it were present.

Hmm, where you doing a level sweep test? I couldn't work out how to do this correctly as I was seeing no hump, but the distortion lines where clearly visible when looking at the spectrogram of a recording of the Cmajor test file.

Seeing that some manufacturers have fixed this through a software update, I think the issue can be dismissed by learning to choose Cirrus DACs that at least have the option to disable DRE, or DACs from another manufacturer

Yeah, I specifically bought a DAC with the switch (the Fiio melody). Alternative non-cirrus ones I looked at with the same features I wanted where more expensive (although they usually provided more power).

 

[IsaacOscar]

EDIT: it seems both the C major and song of the sisters are causing a clicking/ratling soubd ib my headphones (Sennheiser HD 558) (regardless of what DAC I'm using). This doesn't happen with my earphones. I've never noticed anything like this in my years of using them....
I really like my headphone's sound, so I don't want to buy new ones...

Maybe there's something loose inside them that's rattling? I'll open them up and inspect them another day.

In case anyone's interested, here is what my headphone driver does when I play the C major file at the maximum volume on my DRE-disabled Fiio Melody (which is too loud for me to actually put on my head):

https://v.redd.it/0agq11lq21kg1/HLSPlaylist.m3u8

It looks like this is just stressing the driver too much so I might be damaging it by playing the C major file..

 

[Alou]

In case anyone's interested, here is what my headphone driver does when I play the C major file at the maximum volume on my DRE-disabled Fiio Melody (which is too loud for me to actually put on my head):

https://v.redd.it/0agq11lq21kg1/HLSPlaylist.m3u8

It looks like this is just stressing the driver too much so I might be damaging it by playing the C major file..

I wonder besides testing purposes if all these headphones were expected to play normal in such conditions.Yes probably the can handle momentary sparks but constantly it might damage the drivers and or your ears i guess.A lab or a factory uses other tools to evaluate .Also at extremely high volumes the ear "mechanism" starts to develop fatigue and delivers to the brain inaccurate results.Its ok once for test at home but for longer times its a bit risky isnt it?

 

[IsaacOscar]

ll .Also at extremely high volumes the ear "mechanism" starts to develop fatigue and delivers to the brain inaccurate results.Its ok once for test at home but for longer times its a bit risky isnt it?

When not on my head, full volume is not very loud (my phone's speaker is louder)

When on my head, I put it at my normal loud listening volume (50–60%) and that rattling wasn't extra loud or painful. It's just annoying and not present when using earphones (hence me thinking there was something stuck in my headphones that might be causing it...).

It's not a problem as it has never occurred in my many years of using my headphones. It's curious though that the same files that show the Cirrus hump distortion also ellicit this rattling.

 

[Alou]

Maybe a small plastic inside or something got unglued so to speak.if it happens with other audio as well might be something,if only with the specific files maybe the frequencies cause resonance.

 

[tccalvin]

Interestingly, I can't seem to reproduce the aberrant behavior of the Apple 3.5mm dongle with my M3 Macbook Air, even though it sounded like some people were seeing the same problems with their Macs. Wonder if Apple has patched it?
edit: guess the distortion is still there in the CMaj test, but very faint compared to the dongle.

My M4 Macbook Pro:

Extremely faint vertical lines. Has Apple been reading ASR?

Some extra tests just for fun:

Minimum phase filter:

Inter-sample clipping goes away by lowering the OS volume (as expected):

Next time you're using your Mac's headphone jack as a line out to play music don't set volume to the max (Track 2 was at -5 clicks).

 

[IsaacOscar]

My M4 Macbook Pro:

View attachment 512106

Extremely faint vertical lines. Has Apple been reading ASR?

There seems to be a lot of extra noise compared to the other measurements posted here, so they may be masking the lines (or it could just be your software colouring the spectrogram differently...)

Inter-sample clipping goes away by lowering the OS volume (as expected):

View attachment 512109

I've heard of this problem with other DACs before (that full volume has more noise/distortion); how do I run the test to see if my DACs have it?

 

[tccalvin]

There seems to be a lot of extra noise compared to the other measurements posted here, so they may be masking the lines (or it could just be your software colouring the spectrogram differently...)

That's because I had to set the spectrogram to display -120dBFS to even see the lines lol (they were not visible at -96dBFS which is my usual threshold). Also, I record slightly below 0dBFS to avoid clipping because the UA Volt 2's ADC has analog gain pots and it's impossible to get a steady value. In reality, the clicks will be a tad bit louder than shown (around +3dB).

I've heard of this problem with other DACs before (that full volume has more noise/distortion); how do I run the test to see if my DACs have it?

You play this test file through your DAC at max volume and record it. Then you lower the volume and check if the distortion is gone. That's how I run the test anyway. You could go even deeper and check how much headroom (dB) your DAC has before going into overload (as described in the linked post).

 

[reallystate]

HiBy W3 II has been tested for defects from amplifier operation in the class H and DRE-related distortion.

 

[confucius_zero]

has there been any news of the Protocol Max's ability to remove DRE? I just received the TRN BlackPearl and I can't seem to find the DRE switch in the Walkplay interface. I assume, as reported by the asr thread, the firmware does an auto-removal of it.

 

[Alou]

I am wondering if the DRE off ,when applied , if it alters the output in anyway.Yes it cuts the distortion but will it cut anything else ,frequencies ,resolution etc in any way ?

 

[reallystate]

I am wondering if the DRE off ,when applied , if it alters the output in anyway.Yes it cuts the distortion but will it cut anything else ,frequencies ,resolution etc in any way ?

Disabling DRE slightly increases the noise level, eliminates increased distortion at certain signal levels (Cirrus Hump), and also restores good linearity.

However, operating the amplifier in Class H, even with DRE disabled, potentially leads to increased intermodulation and multitone distortion. You can see examples of this at high signal levels in the HiBy W3 II measurement published a couple of posts above.

 

[IsaacOscar]

I am wondering if the DRE off ,when applied , if it alters the output in anyway.Yes it cuts the distortion but will it cut anything else ,frequencies ,resolution etc in any way ?

See https://www.audiosciencereview.com/...usb-dac-headphone-amp-with-10-band-peq.64331/ for measurements of the TRN black pearl comparing DRE on and off.

It shouldn't make a difference to anything other than noise and distortion, and only on low volunes (less noise with DRE on, and less distortion with it off). From my very quick testy of the Fiio Melody, I noticed no audible difference. (but it has a firmware update that makes DRE activate less often).