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

[CedarX]

Just a little observation as I don't think anyone has commented on this.

In the screenshots of @jkim 's tests in the first post of this thread, the JCally JM20 Max has ultrasonic images/reflections of the playback signal (test signal in this case), highlighted in red below:

View attachment 509431

While the JCally JM20/JM28 is clean:

View attachment 509432

Does the JM20 Max do this at all times? If yes, what could be causing it? The SGM8262-2 in the JM20 Max? Or something else?

The ultrasonic content appears to mirror the main signal spectrum, but not exactly. Opamp (-) rail charge pump?

 

[tccalvin]

Does the JM20 Max do this at all times? If yes, what could be causing it? The SGM8262-2 in the JM20 Max? Or something else?

If there are ultrasonic images then the culprit is most likely the low-pass filter. Maybe the default filter is a slow/weak one, or maybe that filter was selected by mistake.

The ultrasonic content appears to mirror the main signal spectrum, but not exactly.

@CedarX I believe that spectrum is exactly what you would expect to see when a reconstruction filter is not working:

 

[Weastony]

One surefire way to know for a fact that a reviewed device does not have Cirrus Logic DRE issues is to immediately disregard the product if it uses a Cirrus Logic chip DAC.

The only way to teach them a lesson is to boycott their stuff, and stick to ESS, AKM, Rohm, etc.

This is a very strange decision. Cirrus Logic-based devices are very inexpensive, they're portable, they have enough power for 99% of headphones, and there's no noise. We should be grateful that we now get the purest sound for almost zero money. Before this thread started, I hadn't seen a single complaint from anyone about these clicks (except for the RAA). This tells us that this "problem" has nothing to do with normal music listening. We simply shouldn't care about this when we listen to music. Of course, Cirrus Logic needs to take steps to fix this issue.

I'm also very disappointed that Amir doesn't devote sufficient attention to most budget devices. These measurements are meaningless as long as they are not comprehensive.

 

[SoySalsaPicante]

This is a very strange decision. Cirrus Logic-based devices are very inexpensive, they're portable, they have enough power for 99% of headphones, and there's no noise. We should be grateful that we now get the purest sound for almost zero money. Before this thread started, I hadn't seen a single complaint from anyone about these clicks (except for the RAA). This tells us that this "problem" has nothing to do with normal music listening. We simply shouldn't care about this when we listen to music. Of course, Cirrus Logic needs to take steps to fix this issue.

I'm also very disappointed that Amir doesn't devote sufficient attention to most budget devices. These measurements are meaningless as long as they are not comprehensive.

Perhaps it is just me, but my perspective on this is that Cirrus Logic deliberately built this function with the express desire to cheat on tests.

Cheating is cheating. I won't give my money to cheaters.

 

[tccalvin]

Perhaps it is just me, but my perspective on this is that Cirrus Logic deliberately built this function with the express desire to cheat on tests.

Cheating is cheating. I won't give my money to cheaters.

Intentional or not, DRE artifacts do elude all traditional measurements, which is why I'm also disappointed that Amir would allow manufacturers to game the system.

My take is that measurements should speak for themselves. It's fine to point out that DRE artifacts will not destroy your music and that you won't hear them most of the time.

Still, if I were going to spend anything more than 10€ (Apple dongle money) on a DAC, I would like it to not have those annoying clicks.

 

[zany.ninja]

If there are ultrasonic images then the culprit is most likely the low-pass filter. Maybe the default filter is a slow/weak one, or maybe that filter was selected by mistake.

I don't think it is the filter. According to @jkim 's review of the JM20 Max the filter is minimum phase (fast roll-off). And its filters are not user selectable AFAIK.

 

[tccalvin]

I don't think it is the filter. According to @jkim 's review of the JM20 Max the filter is minimum phase (fast roll-off). And its filters are not user selectable AFAIK.

weird

 

[pioterd]

Am I right in thinking the KA11 has it's own problem in terms of heat during use?

Not a problem. It has SGM8262 amplifier (mediocre but praised; why not use better OPA1656 instead??? Ah, yes - $$$ -.-) with not much space around. That's why it gets warm, but not hot, do not worry. 40 Celsius degrees is not dramatic, normal for such a compact design. Shanling UAmini is the same, no problems.

According to this CS431XX distortion thing. Maybe for some engineers 130page manual + additional complementary documentation is too much. No worries, Wolfson chips are not for everyone. Shanling/ONIX and Fosi audio know how to implement it well from the scratch. Fiio gave updates which do not fix problem completely - but at least they reacted, absolution will be given. If it's not audible, who cares at the end of the day? "Not important but existing problem-diggers". That's what you call science?;-)

 

[Alou]

Not a problem. It has SGM8262 amplifier (mediocre but praised; why not use better OPA1656 instead??? Ah, yes - $$$ -.-) with not much space around. That's why it gets warm, but not hot, do not worry. 40 Celsius degrees is not dramatic, normal for such a compact design. Shanling UAmini is the same, no problems.

According to this CS431XX distortion thing. Maybe for some engineers 130page manual + additional complementary documentation is too much. No worries, Wolfson chips are not for everyone. Shanling/ONIX and Fosi audio know how to implement it well from the scratch. Fiio gave updates which do not fix problem completely - but at least they reacted, absolution will be given. If it's not audible, who cares at the end of the day? "Not important but existing problem-diggers". That's what you call science?;-)

Maybe because SGM8262 is Chinese ?

 

[robbiekhan]

Luxsin replied to me, confirming that the new DAC X8 has an exclusive switch for the DRE function.

I have had the X8 for a couple of weeks now, anything I can test? DRE option exists in the audio menu yes.

 

[tccalvin]

I have had the X8 for a couple of weeks now, anything I can test? DRE option exists in the audio menu yes.

You could run the CMaj test with DRE on and DRE off. That would be sufficient to get an idea of the DAC behavior, I think.

 

[robbiekhan]

I have not read that far back but... What is the cmaj test?

 

[tccalvin]

I have not read that far back but... What is the cmaj test?

It is explained in the very first post under the "Part II: Another Testing Method" section.

 

[robbiekhan]

It is explained in the very first post under the "Part II: Another Testing Method" section.

Hmm seems I don't have the means to do this test, or I need to do some further research perhaps

 

[IsaacOscar]

Hmm seems I don't have the means to do this test, or I need to do some further research perhaps

Well they're are three easy ways to do it:

1. Play the original C major file with sensitive IEMs at -15dBFS (foobar let's you set volume by dBFS), and compare it to the files recorded from the different devices. (I tried this, but couldn't hear any difference between them, but if you can here clicking on one of the pre-recorded ones, but not on your device, you should be good):
2. Connect a cable from you're devices output to an input port (e.g. a line in or microphone port on your computer); play the major file and record it. Then view the spectrogram of the recording and see that you don't get any vertical lines. You can use Audacity for this, or the multitone loopback analyzer (which is much easier as it starts recording at the same time it starts playing the file).
3. Same as above, but do a 32-tone multitone level sweep, which gives you a graph of distortion vs volume, and check that there's no hump. You can use the multitone loopback analyzer for this (I don't know how to do this one properly, I think you need to get the right settings in multitone).

 

[robbiekhan]

Method 2 seems the most practical so will try this as soon as I have configured some hardware for line in capability to record.

 

[IsaacOscar]

Method 2 seems the most practical so will try this as soon as I have configured some hardware for line in capability to record.

Oh, and as a control you should probably play one of the bad pre-recorded cmajor files (i.e. one that has the lines in the spectrogram), and check that after recording with your line in, you can still see the lines. If you can't, then it means either your DAC or ADC is too noisy for this test to give reliable results...

 

[CedarX]

Method 2 seems the most practical so will try this as soon as I have configured some hardware for line in capability to record.

Although Method 1 is what matters in the end: if you can’t hear the “clicks” from a specially crafted file, DRE probably doesn’t matter much in the end (it has remained unnoticed for years).

 

[IsaacOscar]

Edit: actually, now that you posted a comparison graph I can just barely make out the vertical stripes on your own graph as well! (Cirrus Hump confirmed)

Yup, for the last 5 years or so all my music has been tainted! (in actuality I cannot hear these clicks no matter how hard I try or what volume level I use...)
So after taking a break from this, I've re-recorded things and now the lines are blindingly clear:

It seems what I did wrong last time was playing it at -15dBFS (perhaps my DAC isn't as loud as the other ones that were tested?)

I still can't work out how to show the hump on a level sweep though:

Oh and I hear the clicks now when playing it and the Song of the Sisters, which I don't hear when I use a non-cirrus DAC (I actually hear it more clearly with my headphones than earphones). Maybe my ears were just not working last time I tested it?

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.

 

[robbiekhan]

Although Method 1 is what matters in the end: if you can’t hear the “clicks” from a specially crafted file, DRE probably doesn’t matter much in the end (it has remained unnoticed for years).

I will of course try this first as that makes sense and is what matters to me most, I never knew about the CS click, nor have I heard it on the X8 at any volume so far. Bearing in mind that DE is set to off by default though. It sounds just as clean as any other DAC I have on the bench.