Moondrop Chu II DSP - EQ Review

[CedarX]

Mutiple issue can exist, sure.
I'm simply pointing out UAPP is picky and causes issues in numerous setups before anyone starts mixing up issues on that end.

Not all Chu 2 DSP users seem to experience the same range of issues with calls though?

I have read in multiple places that there can be only one audio driver active at a time on Android (don’t know if it is version-specific, or has always been, and is still true…). When you stop playing a track with UAPP, UAPP is supposed to release its driver—for lack of better words—and hands back the audio control to the default Android audio driver. That driver release process appears to be a recurring problem on Android…
What happens when you take a phone call while playing tracks with UAPP… I don’t know! Speculating… it could be that Chu-II is still expecting hires PCM… because that’s what UAPP “tells” Chu-II. Hence no sound or garbled sound…

All of that to say that I believe you are right to point that UAPP can be picky…
There may be some fundamental incompatibility with Chu-II DSP not allowing seamless transitions between playing hires files (UAPP) and phone calls, it’s either/or, not both…

 

[Eary]

Not all Chu 2 DSP users seem to experience the same range of issues with calls though?

Again it's with Samsung phones, as I posted some links earlier I am not the only person with the issue, I have more links if you want.

https://r2.community.samsung.com/t5/Galaxy-S/Type-C-earphone-are-not-working-for-voice-calls/td-p/16033367

Here is another case of this happening. I don't know what it is but it's not just me.

I’m with @markanini on this one: this about disrupted phone functionality.

I don't think they referred to Chu II disrupting phone functionality, I think they referred to UAPP:

Disrupting call functionality might just be unevitable with some setups, given that UAPP takes direct control of the DAC by design.

They are referring the entire problem to be a UAPP thrid party APP disrupting call functionality. My reply was trying to make clear that I do not hae UAPP installed and yet I have the phone call issue.

When you say “works” you refer to the phone functionality? Playing music tracks? Both? What does work with Chu-II DSP connected Samsung phone, and what does not work?

Chu II DSP works with Samsung phones on video and music playing, I have no problem with media consumption. But when I am taking a walk wearing Chu II DSP and my family member calls me through regular dialing nummers or calls me through WeChat voice-call, I hear their voice completely made out of statics, right now I have to take off the IEM and put the phone screen beside my ear to make or answer a phone call.

 

[Eary]

I have a Sony 3.5mm wire IEM and a 3.5mm to type C dongle DAC, the dongle DAC works with Samsung phone on both media playing and phone cals. So Samsung phone definitely works with my dongle DAC, it's just not the Chu II DSP. What a pity since the DAC is having connection problems when you walk with the phone in hand (when the dongle gets drifted back and forth) and I was trying to get the DAC retired by buying Chu II DSP.

 

[CedarX]

I have a Sony 3.5mm wire IEM and a 3.5mm to type C dongle DAC, the dongle DAC works with Samsung phone on both media playing and phone cals. So Samsung phone definitely works with my dongle DAC, it's just not the Chu II DSP. What a pity since the DAC is having connection problems when you walk with the phone in hand (when the dongle gets drifted back and forth) and I was trying to get the DAC retired by buying Chu II DSP.

Ok so you have a Samsung phone, and no other phone, and don’t use UAPP (not even installed). Correct?
And what doesn’t work with Chu-II DSP is the phone functionality. Correct?
Playing YouTube videos with Chu-II DSP does work—the sound is ok. Correct?

Sorry for the questions, but I am confused by what you are reporting and I have a hard time understanding what is it exactly… it looks to me that you are only talking about phone functionality (as @gcompari by the way…).

The fact that the phone functionality works on your Samsung phone when connected to a “Type-C dongle DAC” (your words) doesn’t say much… What brand & model of dongle? Is it UAC 1.0 or 2.0 compliant?

 

[Eary]

Ok so you have a Samsung phone, and no other phone, and don’t use UAPP (not even installed). Correct?
And what doesn’t work with Chu-II DSP is the phone functionality. Correct?
Playing YouTube videos with Chu-II DSP does work—the sound is ok. Correct?

Yes all correct.

The fact that the phone functionality works on your Samsung phone when connected to a “Type-C dongle DAC” (your words) doesn’t say much… What brand
& model of dongle? Is it UAC 1.0 or 2.0 compliant?

Not sure, I bought a random one online, it's written on its body that it's "HIFI Audio Adapter" and "Max PD60W 20V/3A 32BIT/384KHZ", there is no info about the brand.

Before I used this dongle I was using another dongle that I bought along with the Samsung phone, recommended by the BestBuy staff. That dongle had the same overall appearance as my current one, with both the 3.5mm input for headphone and a fast charge type C input for charging, basically enabling the ability to listen through headphone while charging the phone. The old dongle broke pretty much the same way: connection issue when swinging around.

Looks pretty much like this one: https://www.walmart.com/ip/USB-C-3-...-Samsung-Galaxy-S22-S21-S20-FE-Ult/1311415908

 

[CedarX]

Yes all correct.



Not sure, I bought a random one online, it's written on its body that it's "HIFI Audio Adapter" and "Max PD60W 20V/3A 32BIT/384KHZ", there is no info about the brand.

Before I used this dongle I was using another dongle that I bought along with the Samsung phone, recommended by the BestBuy staff. That dongle had the same overall appearance as my current one, with both the 3.5mm input for headphone and a fast charge type C input for charging, basically enabling the ability to listen through headphone while charging the phone. The old dongle broke pretty much the same way: connection issue when swinging around.

Looks pretty much like this one: https://www.walmart.com/ip/USB-C-3-...-Samsung-Galaxy-S22-S21-S20-FE-Ult/1311415908

Notice that the one you linked at Walmart explicitly says “for Samsung…”, not “For Android…”. To me, this hints something possibly unique about Samsung phones.

32bit/384kHz means it’s UAC 2.0 compliant, Chu-II DSP is UAC 1.0.

Pure speculation: is it a case where Samsung smartphones phone functionality does not work with—
1. UAC 1.0 devices?
2. Some KTmicro chips (e.g. KT210)?
3. Chu-II DSP, because of some custom FW from Moondrop?

 

[Eary]

Pure speculation: is it a case where Samsung smartphones phone functionality does not work with—
1. UAC 1.0 devices?
2. Some KTmicro chips (e.g. KT210)?
3. Chu-II DSP, because of some custom FW from Moondrop?

Maybe the reason is one of these points, no idea. I mentioned I reported this back to Moondrop's customer service but I don't really see hope in my product getting fixed. I guess I have tried my best to be a responsible customer, to let the manufacturer know about their bad user experience so later customer can potentially recieve fixed product. But my case, I guess I have to live with the inconvenience of taking the IEM off for phone calls, until the IEM is worn enough that I can have excuses to buy a new one.

A separate unrelated question though, is there a difference between the in-cable 5-band EQ vs 5-band EQ with the same parameters loaded in software like EqualizerAPO? Is there a difference in quality or is it completely the same?

 

[CedarX]

Maybe the reason is one of these points, no idea. I mentioned I reported this back to Moondrop's customer service but I don't really see hope in my product getting fixed. I guess I have tried my best to be a responsible customer, to let the manufacturer know about their bad user experience so later customer can potentially recieve fixed product. But my case, I guess I have to live with the inconvenience of taking the IEM off for phone calls, until the IEM is worn enough that I can have excuses to buy a new one.

A separate unrelated question though, is there a difference between the in-cable 5-band EQ vs 5-band EQ with the same parameters loaded in software like EqualizerAPO? Is there a difference in quality or is it completely the same?

To be fair, Samsung is not completely innocent here!

As for your question Chu-II DSP vs. EqAPO: PEQ filters implementation can vary, but first, I’m not sure the differences are audible, and second, it doesn’t really matter: regardless of the source you use to develop your EQ (Amir’s measurements, Oratory, AutoEQ repository, etc.), it’s never going to be perfect for your ears, how you perceive the sound, and your taste. So, you’ll have to make some manual adjustments… At this point, potential implementation differences between EQs become irrelevant since you adjust around “manually”.

As for sound quality, the DAC/Amp chip used in Chu-II DSP is not exactly SOTA, but most likely good enough for IEMs used in a mobile scenario. EqAPO… well, it’s a software, so it all depends on what DAC/Amp you use!

 

[mc.god]

In regard to UAPP issue with phone calls there are some note on last version changelog:

So playing with options may help.

Just to contribute since I don't use my dongles on smartphone at all so I'm not experienced with this.

 

[gcompari]

I don't think many on ASR care about hi-res audio. Just stating the facts. You can search about the topic if you want to know why or start a new thread.

You're saying you tried ten phones and they permanently lost call functionality when you installed an app for hi-res audio playback? Honestly, that doesn't make sense, at least not as an IEM issue. I'd recommend looking for a UAPP support channel. That will probably get you closer to the solution you want. Starting a debate about IEM design won't help much, and is off-topic in this thread.

I don't think many on ASR care about hi-res audio. Just stating the facts. You can search about the topic if you want to know why or start a new thread.

Hi-Res (at least for me, but not only for me) is all audio content >CD quality, i.e. >44.1kHz sampling rate and >16bit ( https://en.wikipedia.org/wiki/High-resolution_audio ).
Do you think people that visit AudioScienceReview forum reads reviews about SINAD of 120dB or more and DR of 130dB and so on only to listen mp3 or CD tracks with a theoretical maximum SNR of 16 * 20 * LOG(2) + 10 * LOG(3/2)= 96.33+1.76 = 98.02dB, and a minimum theoretical THD of 0,0015% (w/o dithering)? Sorry, but probably are you that:

might feel out of place on ASR

You can search about the topic if you want to know why or start a new thread.

Sorry, I have no time to start a new topic or search about a supposing disinterest about Hi-Res in ASR.

Starting a debate about IEM design won't help much, and is off-topic in this thread.

I didn't start any debate about IEM design: I just answered to a post that asked me why I'm interested on Moondrop Chu II and not (or less) on ThrutEar x Crinacle Zero:RED.

You're saying you tried ten phones and they permanently lost call functionality when you installed an app for hi-res audio playback?

I never sad that.

I'd recommend looking for a UAPP support channel.

They may tell me why the Chu II DSP with Samsung S22 and w/o installed UAPP doesn't work...

 

[gcompari]

I think gcompari is talking about two separate issues
1. For Samsung phones, phone calls with Chu II DSP never works, I have a Samsung phone, i tried using another 3.5 mm headphone connect with the dongle dac works with phone calls, but Chu 2 dsp doesn't. When you make a phone call, what you hear always sounds distorted, it sounds like when you set the buffer size of your sound card very low for a low latency number, and it sounds distorted, It's like the entire sound has turned into just full of statics. I searched on net, and it seems like people with Samsung phones face the same issue when using Chu II.
example:

Using Moondrop CHU2 DSP for taking calls | The Indian Audiophile Forum

I received Moondrop CHU2 DSP today and it sounds amazing. But when I use it to take calls or make calls, I hear a crackling noise and it is completely unusable. I am using it with my Galaxy s24 phone. Do anyone have a similar issue?

www.theindianaudiophileforum.com

https://eu.community.samsung.com/t5/galaxy-s24-series/moondrop-chu-ii-2-dsp-distorted-audio-on-calls/td-p/11161312

2. gcompari's second point is that some other phones have issued in playing high res audio. Since i don't have a need for playing high res, i don't really know about this one.

Note ever since gcompari brought up this topic in the thread, I reported again to the customer service, telling them to report to the technical staff, It just doesn't make sense if everybody with the Samsung phone faces the same issue, but the technical staff of the brand just doesn't know about this. They said that they have told the technical staff about this, but i never got a reply afterwards, I'm not sure.

1. Exact. Thank you to understand me. With my Samsung S22 (also not using UAPP or deinstalling it) is it impossible to make/answer a call with the Chu II DSP: always I can hear only very corrupted sounds.
2. The S22 and all phones i tested work with UAPP and the Chu II DSP to listen a track until 96/24. Always. But with my S22 I can't use the Chu II DSP to answering to a call. Always. With all the other phones I tested, after a session of UAPP, I must disconnect the Chu II DSP to use it for making/answering a/to call; w/o using before UAPP the Chu II DSP work flawlessly.

 

[markanini]

I never sad that.

The problem is that using the Moondrop Chu II DSP with all the phones I have tried (about ten by now) you lose the ability to use the phone if you use USB Audio Player Pro and with the Samsung S22 the phone no longer works at all because it can only play music tracks (even uninstalling UAPP): you can no longer make or receive calls.

Then "lose the ability" is an incorrect description. UAPP is in fact working as intended, taking over control of the DAC. You can test the workaround, changing options for transient audio focus loss. https://www.audiosciencereview.com/...ndrop-chu-ii-dsp-eq-review.53470/post-2161053 First however the Samsung specific issue needs a solution if you want to use that phone. Or let go of the hi-res requirement, human hearing thresholds don't justify its use.

 

[gcompari]

Disrupting call functionality might just be unevitable with some setups, given that UAPP takes direct control of the DAC by design. It would be prudent to select a verified DAC + phone combo beforehand if it's a hard requiremt. That's why I asked why he needs hires playback, because of the potential hurdles. The Nyquist theorem doesn't suggest it's worth the hassle, and he's already complaining about the issue he's having.

The Nyquist theorem doesn't suggest it's worth the hassle

https://en.wikipedia.org/wiki/Hearing_range -> "humans can hear sound as low as 12 Hz and as high as 28 kHz"
The Nyquist-Shannon theorem suggest (or better "states") that w/o Hi-Res you can't reach nothing more 22050Hz. My son (10 years old) can hear w/o problems 22.000Hz.

In the “Master Handbook of Acoustics”, F. Alton Everest states: “The SNR of a PCM 16 bit system seems adequate only for piano solos. Further developments will undoubtedly require greater dynamics than that offered by 16-bit digital systems”.

 

[gcompari]

Then "lose the ability" is an incorrect description. UAPP is in fact working as intended, taking over control of the DAC. You can test the workaround, changing options for transient audio focus loss. https://www.audiosciencereview.com/...ndrop-chu-ii-dsp-eq-review.53470/post-2161053 First however the Samsung specific issue needs a solution if you want to use that phone. Or let go of the hi-res requirement, human hearing thresholds don't justify its use.

Then "lose the ability" is an incorrect description.

Sorry, but for me if I listen a track with UAPP and I need to answer to a call or make a call and I have to disconnect/reconnect the IEMs from/to my phone wich is in my backpack is equivalent to "lose the ability" to use my phone as a phone. It is only an audio player.

 

[gcompari]

Maybe the reason is one of these points, no idea. I mentioned I reported this back to Moondrop's customer service but I don't really see hope in my product getting fixed. I guess I have tried my best to be a responsible customer, to let the manufacturer know about their bad user experience so later customer can potentially recieve fixed product. But my case, I guess I have to live with the inconvenience of taking the IEM off for phone calls, until the IEM is worn enough that I can have excuses to buy a new one.

A separate unrelated question though, is there a difference between the in-cable 5-band EQ vs 5-band EQ with the same parameters loaded in software like EqualizerAPO? Is there a difference in quality or is it completely the same?

Some other news:
- I called the Moondrop Support. They told me to contact the dealer: I don't understand what the dealer may know about the internals of the MoonDrop Chu II DSP, but I called the dealer and they forwarded my question to Moondrop. Moondrop answered to the dealer wich answered me. We are going back and forth through the dealer...
Moondrop (trough the dealer) told me that: "Hello, this is because the exclusive mode is turned on. If the exclusive mode is turned on, other applications will not be able to use the DSP. Please try to turn it off.". But I can't find in my S22 (Android 14) the Exclusive Mode setting.
I "started" a "me -> dealer -> Moondrop -> dealer ->me" new "transaction" and I got:
"To turn exclusive mode on or off on the Samsung Galaxy S22, you can follow these steps:
1. Open the phone's "Settings" app.
2. In the settings menu, find and tap the "Sounds and Vibration" option.
3. In the Sounds and Vibration settings, find and tap the "Advanced" option.
4. In the Advanced settings, find and tap the "Exclusive Mode" option.
5. In the Exclusive Mode settings, you can choose to turn exclusive mode on or off."
But in my S22 there isn't the "Advanced" option in the "Sounds and Vibration..." with or w/o enabling the "developer options" of the Android 14.

- With all other phones it seems that playing Hi-Res tracks with PowerAmp Pro works flawlessly, but I don't know if PowerAmp desample the tracks or really push the Chu Ii DSP to 96/24. I'll try with Neutron, but I don't know if Neutron shows the "real" current state of the USB external DAC as UAPP shows.
So, if PowerAmp or Neutron work w/o problems with Chu II DSP @96/24, I can see three areas of investigation:
- UAPP sets something in the DSP cable that make the cable don't work anymore with Android.
- UAPP sets something in Android and Android can't drive the Chu II DSP anymore.
- UAPP don't release the control of the Chu II DSP, even if the App was stopped and removed from memory.

 

[Eary]

3. In the Sounds and Vibration settings, find and tap the "Advanced" option.

I have Samsung A53 5G, there is no "Advance" submenu in the "Sounds and Vibration" settings.

 

[markanini]

Sorry, but for me if I listen a track with UAPP and I need to answer to a call or make a call and I have to disconnect/reconnect the IEMs from/to my phone wich is in my backpack is equivalent to "lose the ability" to use my phone as a phone. It is only an audio player.

Then you don't understand the purpose of the app and are complaining about it for working correctly, in the wrong thread.

 

[gcompari]

I have Samsung A53 5G, there is no "Advance" submenu in the "Sounds and Vibration" settings.

I ordered the Moondrop FreeDSP cable to see if the problem is related in general to the "active" USB-C Moondrop cables with Samsung S22 (and from what I've seen in this thread also with A53, S20, S21, S23 and S24 in the non Plus or Ultra version).
It finally arrived and I was able to try it.
The FreeDSP cable works perfectly with S22: you can make calls and listen to Hi-Res music.
The problem with the Chu II DSP working with S22 seems to be connected only to the use of the Moondrop CDSP cable included with the Chu II DSP.
From the tests I've carried out, the problem remains (as with all the other phones I've tested) that after using UAPP even just once, you can no longer make calls.
It is always necessary to disconnect the FreeDSP and reconnect it to be able to receive or make calls.
Now I'll try Neutron to see if the problem concerns the Moondrop DSP cables and UAPP only.
From my tests, the Moondrop FreeDSP cable works at 16/24/32 bit, but only at 44.1, 48, 96, 192, 384 kHz: it does not work at 88.2, 176.4 and 352.8 kHz.
In my case 88.2/24 is for the majority of Hi-Res audio tracks I own.
The Moondrop CDSP cable included with the Chu II DSP also works at 88.2/24 (in addition to being lighter, less bulky and more flexible, and costing 5 times less if purchased with the Chu II).

 

[gcompari]

Then you don't understand the purpose of the app and are complaining about it for working correctly, in the wrong thread.

A) This thread is about the Moondrop Chu II DSP.
B) The Moondrop Chu II DSP comes with a microphone, a DAC, a DSP and a headphone amplifier.
C) The Moondrop Chu II DSP's DAC plays 16 and 24-bit tracks, at 44.1kHz, 48kHz, 88.2kHz, 96kHz.
D) The Moondrop Chu II DSP's performance is very interesting for Hi-Res listening.
E) The presence of a microphone makes them very convenient because you can use the phone as a HiFi chain to listen to music and make/receive phone calls without having to do complicated operations to switch from one function to another.
F) In order to use the 24-bit playback modes and frequencies higher than 44.1kHz/48kHz (which is what the Moondrup Chu II were designed for), you need an application that is able to drive an external 24-bit USB DAC at frequencies higher than those provided internally by Android.
G) UAPP is one of the most popular applications (perhaps the first ever made and perhaps also the most popular) that allows you to drive a DAC as in point (F).
H) The Moondrop Chu II DSPs seem to have problems with many of the most popular Android phones and UAPP for which many of the participants in this discussion (except a few) would like to find a solution because they bought them and would like to use them with all the features they are designed for.
Can I know why I'm in the "wrong thread"?
Maybe someone has time to joke: I don't.

 

[CedarX]

Can I know why I'm in the "wrong thread"?

It may be because your point H) could be rewritten the other way:

H) UAPP seem to have problems with many of the most popular Android phones and the Moondrop Chu II DSPs for which many of the participants in this discussion (except a few) would like to find a solution because they bought them and would like to use them with all the features they are designed for.

After-all, you said that you experienced the exact same issue with FreeDSP: it also requires a disconnect/reconnecter after using UAPP to receive or make phone calls.

Isn’t more a UAPP issue?