[improwise]

Correct..

USB-C to USB-C will make the ML function as an external DAC/AMP + Headphone

3.5mm to USB-C wil male the ML function as a passive headset (by using unused pins of the USB-C connector to transport the analog signal). Internal DAC/AMP are bypassed.

This was basically my question, if the 5909s with an external DAC and not using the internal one, could sound better or if the built in DAC is considered to be good enough for the headphones capabilities. I realize that that the answer to this might be subjective, as you could probably tweak the sound much more with a high end external DAC. Also, size constraints, weight etc. should probably mean some compromises have been made with the internal one.

Most high end headphones don't have a built in DAC AFAIK so this is somewhat of unknown territory. As I would be mainly using them with a PC when not wireless, not having to use an external DAC would make things simpler, especially when using a laptop.

 

[WDitters]

This was basically my question, if the 5909s with an external DAC and not using the internal one, could sound better or if the built in DAC is considered to be good enough for the headphones capabilities.

Yes... The internal DAC/AMP of the 5909 is great but no match for better dedicated DAC/AMP. From my tests, the order of decreasing quality was:

Best: Source -> Questyle DAC/AMP -> Passive 3.5mm connection to ML5909 (with ML cable)
Maximum resolution: 32/768 Determined by Questyle

Intermediate: Source -> USB-C to USB-C connection into ML5909 internal DAC/AMP
Maximum resolution: 24/96 (ML 5909 hardware limitation)

Worst: Source -> Bluetooth connection to ML5909
Maximum resolution: determined by Bluetooth codec (lossy)

 

[improwise]

Kinda sucks that they wont support Snapdragon Sound/Le Audio.. (Qualcomm QCC 5127) hard pass for me :/

Is LE Audio available yet in some actual devices?

PS Snygg logga/avatar

 

[improwise]

Yes... The internal DAC/AMP of the 5909 is great but no match for better dedicated DAC/AMP. From my tests, the order of decreasing quality was:

Best: Source -> Questyle DAC/AMP -> Passive 3.5mm connection to ML5909 (with ML cable)
Maximum resolution: 32/768 Determined by Questyle

Intermediate: Source -> USB-C to USB-C connection into ML5909 internal DAC/AMP
Maximum resolution: 24/96 (ML 5909 hardware limitation)

Worst: Source -> Bluetooth connection to ML5909
Maximum resolution: determined by Bluetooth codec (lossy)

Thanks for the summary.

Would you be able to get the same bass in a passive 3,5 mm connection (where I think ANC is not an option)? Not sure if it is some kind of hardware limitation or just a matter of EQ.

While highly subjective, how would the 5909 stand up as a passive headphone to the competition? What would be some valid comparisons to some non wireless headphones? It would seem reasonable that maybe 50% of the price for them is probably related to the "non passive stuff" like BT, battery, built in DAC etc.

 

[WDitters]

Thanks for the summary.

Would you be able to get the same bass in a passive 3,5 mm connection (where I think ANC is not an option)? Not sure if it is some kind of hardware limitation or just a matter of EQ.

Mutiple answers:
- If you mean anything else but the neutral setting in the ML app, no you will not be able to access settings such as Enhanced or Attenuated Bass Contour when using passive.
- With the above out of the way, the answer would be that it will depend on the external amp that one uses .. They all have their individual character and will influence the sound of the ML 5909. In my experience, between my Shanling M9, Cayin N8ii and Questyle AMPs I did each time get a different sound signature. Some with more bass, some with less.

While highly subjective, how would the 5909 stand up as a passive headphone to the competition? What would be some valid comparisons to some non wireless headphones? It would seem reasonable that maybe 50% of the price for them is probably related to the "non passive stuff" like BT, battery, built in DAC etc.

The ML5909 definitely are good headphones in their own right. But you already gave the answer yourself ... A significant part of the price reflects the wireless capabilities and as such the ML5909 cannot compete with $1000-$1500 wired over ear headphones (closed or open) .. However they compete quite well in the price bracket below I would say ..

 

[improwise]

Mutiple answers:
- If you mean anything else but the neutral setting in the ML app, no you will not be able to access settings such as Enhanced or Attenuated Bass Contour when using passive.
- With the above out of the way, the answer would be that it will depend on the external amp that one uses .. They all have their individual character and will influence the sound of the ML 5909. In my experience, between my Shanling M9, Cayin N8ii and Questyle AMPs I did each time get a different sound signature. Some with more bass, some with less.



The ML5909 definitely are good headphones in their own right. But you already gave the answer yourself ... A significant part of the price reflects the wireless capabilities and as such the ML5909 cannot compete with $1000-$1500 wired over ear headphones (closed or open) .. However they compete quite well in the price bracket below I would say ..

Thanks again for a detailed answer. Much appreciated. I would assume that ANC is mainly some DSP combined with microphones, but as mentioned above, non of the settings in the app seemed to be close to give me the same bass as with ANC enabled. That had me thinking if it was some kind of "trickery" that an external DAC/AMP would not be able to access (even though I can't think of how this could be).

 

[angelom]

Kinda sucks that they wont support Snapdragon Sound/Le Audio.. (Qualcomm QCC 5127) hard pass for me :/

And one strange thing: "For some reason, T+A Elektroakustik has not included AAC support"

 

[MayaTlab]

Thanks again for a detailed answer. Much appreciated. I would assume that ANC is mainly some DSP combined with microphones, but as mentioned above, non of the settings in the app seemed to be close to give me the same bass as with ANC enabled. That had me thinking if it was some kind of "trickery" that an external DAC/AMP would not be able to access (even though I can't think of how this could be).

Cf link above to ASR, it's the feedback mechanism at play. For this the internal DSP needs to have access to the feedback microphone inside the earcup, which would be located here (red arrow, but not shown in this - not fully realistic - exploded view) in the case of the 5909 (too bad the FCC filing photos don't show it) :

Most current ANC headphones feature a feedback mic, a basic implementation with electret mics typically looks like this :

 

[improwise]

Cf link above to ASR, it's the feedback mechanism at play. For this the internal DSP needs to have access to the feedback microphone inside the earcup, which would be located here (red arrow, but not shown in this - not fully realistic - exploded view) in the case of the 5909 (too bad the FCC filing photos don't show it) :



Most current ANC headphones feature a feedback mic, a basic implementation with electret mics typically looks like this :

Thanks. I actually tried looking at that link before but my head was spinning after the first paragraph, is there a Feedback mechanism for dummies perhaps?

This seems to be a good starting place for us mere mortals:

https://www.soundguys.com/noise-canceling-anc-explained-28344/

They actually have a nice article about USB-C headphones as well:

https://www.soundguys.com/usb-audio-explained-18563/

Edit:

Perhaps I am not just smart enough but does this mean that an external AMP/DAC would be able to generate the same amount of bass even though not having access to the ANC/Feedback mechanism? If that is the case, how come there does not seem to be an option to have the same bass without ANC (at least not without an external AMP/DAC AFAIK)? I mean, the drivers and everything should be the same regardless.

 

[C_Lindbergh]

Is LE Audio available yet in some actual devices?

PS Snygg logga/avatar

Not yet, but looks llike phones with the right hardware will support it when Android 13 finally launches.

 

[MayaTlab]

Thanks. I actually tried looking at that link before but my head was spinning after the first paragraph, is there a Feedback mechanism for dummies perhaps?

Not a lot that I'm aware of.

To make it simple : some headphones rely more than others on the earpads sealing well against your head to deliver the bass response they're meant to deliver.

Some of these headphones will seal inconsistently across different users (or even for the same user when you move your head !). This is often the case with Harman's own closed back headphones run passively (or in the case of the ML 5909 - and most other wireless headphones - when ANC is off).
Ex :

https://www.rtings.com/headphones/tests/sound-quality/frequency-response-consistency

The feedback mechanism "EQs" the actual response an individual experiences at a given time in real time, or near real time in some implementations, to ensure that the response is the same no matter how the headphones fit various users.
Ex :

Solderdude at DIYaudio measured the Bose QC35 with varying degrees of leakage with ANC on and off : https://diyaudioheaven.wordpress.com/headphones/measurements/bose/qc35-ii/

Perhaps I am not just smart enough but does this mean that an external AMP/DAC would be able to generate the same amount of bass even though not having access to the ANC/Feedback mechanism? If that is the case, how come there does not seem to be an option to have the same bass without ANC (at least not without an external AMP/DAC AFAIK)? I mean, the drivers and everything should be the same regardless.

Without the feedback mic telling the DSP what the actual response is at lower frequencies (which as said before will vary across users for the ML5909), you have no knowledge of how much compensation would be needed to reach a specific target.
You could EQ up the bass, but to reach the exact same response you'll need to know where you're starting from.

The only way to have the exact same response across various users with both ANC on and off is to have the feedback mechanism works even when ANC is turned off, but to my knowledge only Apple has tried to do it.
Another way would be to have your headphones produce the exact same response by default (without feedback) across various users, but unless they're fully open designs (ex : HD650), I'm not certain that it's truly feasible.

 

[improwise]

Not a lot that I'm aware of.

To make it simple : some headphones rely more than others on the earpads sealing well against your head to deliver the bass response they're meant to deliver.

Some of these headphones will seal inconsistently across different users (or even for the same user when you move your head !). This is often the case with Harman's own closed back headphones run passively (or in the case of the ML 5909 - and most other wireless headphones - when ANC is off).
Ex :

https://www.rtings.com/headphones/tests/sound-quality/frequency-response-consistency

The feedback mechanism "EQs" the actual response an individual experiences at a given time in real time, or near real time in some implementations, to ensure that the response is the same no matter how the headphones fit various users.
Ex :


Solderdude at DIYaudio measured the Bose QC35 with varying degrees of leakage with ANC on and off : https://diyaudioheaven.wordpress.com/headphones/measurements/bose/qc35-ii/



Without the feedback mic telling the DSP what the actual response is at lower frequencies (which as said before will vary across users for the ML5909), you have no knowledge of how much compensation would be needed to reach a specific target.
You could EQ up the bass, but to reach the exact same response you'll need to know where you're starting from.

The only way to have the exact same response across various users with both ANC on and off is to have the feedback mechanism works even when ANC is turned off, but to my knowledge only Apple has tried to do it.
Another way would be to have your headphones produce the exact same response by default (without feedback) across various users, but unless they're fully open designs (ex : HD650), I'm not certain that it's truly feasible.

Thanks for a nice and understandable summary!

This begs the question, should all high end headphones come with ANC, or at least this feedback mechanism? It sounds like (no phun intended) the next big thing for headphones, and not just something for blocking out surrounding noise. If kind of feels like something similar to custom made IEMs.

 

[MayaTlab]

This begs the question, should all high end headphones come with ANC, or at least this feedback mechanism? It sounds like (no phun intended) the next big thing for headphones, and not just something for blocking out surrounding noise. If kind of feels like something similar to custom made IEMs.

If you look at Rtings' consistency data, which at lower frequencies is tested for over-ears on real humans, most fully open headphones (ex : HD650) are quite consistent, even without active electronics. Quite a few high-end headphones are of this type so I'm not certain that they'd necessary benefit from it.

For headphones reliant on seal I guess that it depends on how well designed they are. Some passive closed back headphones on Rtings seem to be reasonably consistent without a feedback mechanism, others not so much.

And so far most headphones featuring a feedback mechanism have had some drawbacks, such as ANC background noises, or - and this is just me having a hunch here - perhaps increased susceptibility to variations between individuals / depending on fit, right above the range where the feedback operates (cf ASR link above, sorry :/).

But yep, it isn't just about noise isolation. As a matter of fact, the Airpods 3 have a feedback mechanism, even though they don't feature ANC. It's used to counteract the wild variations in FR open earbuds can experience.

 

[improwise]

Not sure if I am doing something wrong here (or still not really understanding things) but I tried to install a software EQ to try to improve bass without having ANC enabled, but that just does not seem to work. I was thinking that I would be able to override settings and force more bass but even though it works for my other headphones, it does not seem to work for this one. I can easily verify that the software EQ is in fact working even with the 5909s but its like the extra 10-20% bass just isn't available without ANC. Obviously seal etc. is the same in all test cases. Problem is I find the bass a bit boomy with ANC enabled, but perhaps that is just a limitation of the drivers.

 

[angelom]

Not sure if I am doing something wrong here (or still not really understanding things) but I tried to install a software EQ to try to improve bass without having ANC enabled, but that just does not seem to work. I was thinking that I would be able to override settings and force more bass but even though it works for my other headphones, it does not seem to work for this one. I can easily verify that the software EQ is in fact working even with the 5909s but its like the extra 10-20% bass just isn't available without ANC. Obviously seal etc. is the same in all test cases. Problem is I find the bass a bit boomy with ANC enabled, but perhaps that is just a limitation of the drivers.

Of course the taste for every person is different, and for me the bass with ANC off and bass setting in "neutral" position is very satisfactory. This is how I listening 80% of the time my 5909 (the other 20% is mix of ambient or ANC on with bass in "neutral" position always).

For curiosity, after reading your post, I test the 10 bands EQ from iTunes (Apple Music now) in my MacBook Pro and is working perfectly with the 5909, this meaning that I can changing the sound if necessary, but I never use this EQ.