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Apple AirPods Max Review (Noise Cancelling Headphone)

MayaTlab

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An asymmetry is an asymmetry.

Screenshot 2021-08-12 at 08.35.42.png
Screenshot 2021-08-12 at 08.36.38.png

The HMS II HATS Rtings use shows poor adherence to IEC and ITU standards in the treble compared to the GRAS KEMAR Oratory uses for most of his recent measurements:

Possibly but as I said my observation concerns GRAS rigs as well. All of them are under-representing the ear canal gain region vs. what I am personally getting from the APM (but as I said this is just my own experience).

The fact that you find similar discrepencies with the AKG K371 as the APM strongly suggests in both cases that as I said before this is just down to response variation on different heads (mirrored by small variation in clamping pressure on different rigs), as this is a known issue with the K371.

I probably didn't express myself well enough. The APM and K371 are similar to me insofar as they both have a response below 3kHz that I wouldn't feel much need to EQ, and a pretty uneven response above that's I'd like to EQ. That's where the similarities end (for a start the K371 is unEQable in practice for me because of FR instability when I move about).

Their on-head behaviour under compression is actually radically different. While I can't know what happens with these headphones on a hammerhead style fixture, the AKG K371 on my head, under compression, show an elevated SPL increase across the entire pressure chamber band (ie up to around 4-5kHz at least). The APM on the other hand (and I suspect quite a few ANC headphones), show a similar SPL throughout the ANC feedback range (below 800Hz or so) and a varying SPL above that. So on the K371 compression issues don't affect to quite the same extent the tonal balance of the FR throughout the pressure chamber band, but they do on the APM.
Screenshot 2021-08-12 at 08.49.45.png

Red and orange traces : K371 with a good seal in both case, but with slightly more compression for the orange trace (emphasis on "slight")
Turquoise traces : APM with varying degree of compression.
All done with blocked ear canal entrance measurements (so don't read too much into either the absolute values or even the relative values between the two headphones between 2 and 4kHz, look only at the relative values for the same HP).
Measured after the pads were warmed up (particularly important for me for the K371).
Traces were NOT normalised.
I think that it's quite normal that the response of the APM (or most other ANC headphones with a robust feedback mechanism) doesn't vary below 800hz, as the feedback mechanism applies EQ in real time in that range to deliver the SPL the input tells it to produce. But above that it doesn't work and the usual compression issues apply.

Hence why I suspect that when measuring ANC headphones with a feedback mechanism particular attention should be given to make sure that the overall balance between the ANC feedback range and the ear canal gain region is a good mach for the average human.
And hence why different people may experience quite varying levels of ear canal gain vs. lower frequencies with such headphones.
Oratory mentioned that to facilitate the ANC performance a good pair of ANC headphones may require a low acoustic impedance design, making them more susceptible to variations in the front volume, but I have don't understand what that exactly means and have no idea whether or not this increased susceptibility also applies in the ear canal gain region :D.
But at least as far as I'm concerned from seatings to seatings this issue isn't that prevalent - or at least not anywhere near as significant in the ear canal range than what I've seen from Oratory's spatial averaging graph :
Screenshot 2021-08-11 at 20.34.53.png
APM individual traces with careless positioning. Not the best I've seen, but not the worst either. I'm not getting much variation at 1kHz for example.

The LCD-X's crap stock response and probable non-minimum phase error in the bass (look at the huge group delay swing there, combined with the kink in frequency response)

That could be a HPs to rig interaction problem that you may not experience on your own head.
In the case of the HD58X for example :
https://www.audiosciencereview.com/...nheiser-hd58x-jubilee-review-headphone.25474/
When I measure them on my head :
Screenshot 2021-08-11 at 21.21.33.png
Resolve measured the LCD-X on head as well and noted that his own head measurements didn't exhibit the same "kinks" as his rig's measurement :
HPs to rig interaction issues at lower frequencies - particularly in the form of sharp "kinks" - is something that Solderdude tried to characterise as far as pad compression is concerned for example (what he called "pad bounce") : https://diyaudioheaven.wordpress.com/headphones/earpads/
So I'd take these things with a pinch of salt.
 
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Tircuit

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I’ve played with Amir’s eq in Windows and with Apple’s accessibility options with mine. (I was fine with the stock sound.). Interestingly, for me, the settings do indeed improve overall sound and “space”, but at the cost of fatigue.

I wonder if they found the higher freq dips to give a more laid-back sound.
 

staticV3

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I’ve played with Amir’s eq in Windows and with Apple’s accessibility options with mine. (I was fine with the stock sound.). Interestingly, for me, the settings do indeed improve overall sound and “space”, but at the cost of fatigue.

I wonder if they found the higher freq dips to give a more laid-back sound.
Comparisons to other GRAS measurements of the APM have shown quite a lot of variation above 600Hz, to the tune of 4dB+ difference.
That could easily explain why Amir's EQ sounded good on his unit, but led to overshoot and subsequent fatigue with your unit.
 

MayaTlab

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Comparisons to other GRAS measurements of the APM have shown quite a lot of variation above 600Hz, to the tune of 4dB+ difference.
That could easily explain why Amir's EQ sounded good on his unit, but led to overshoot and subsequent fatigue with your unit.

Less a question of unit variation, but rather of HP / individual interaction though. I'm quite certain that the APM's sample variation is far, far below the variation exhibited across the measurements so far.
 

Zensō

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I’ve played with Amir’s eq in Windows and with Apple’s accessibility options with mine. (I was fine with the stock sound.). Interestingly, for me, the settings do indeed improve overall sound and “space”, but at the cost of fatigue.

I wonder if they found the higher freq dips to give a more laid-back sound.
I tried Amir's EQ and also found it fatiguing. My favorite setting so far is to simply set iOS Headphone Accommodations to Balanced/Slight. This measures as darker than Harman, but sounds similar to various other headphones I have EQ'd to Harman (Focal, Senn, Beyer). When I EQ the APM to Harman using Oratory's preset, it presents as far brighter than my other headphones EQ'd to the same target. Not sure why that is...
 
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Gabe33

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The frequency response is not bad all , you can fix that with like 2 eq filters , compared to the 6-8 filters you need for most refference headphones . Active headphones seem to be the go to for linear frequency response. The AKG N700 Nc is one of the flatest headphones out there . Too bad we dont have open backs for wireless active headphones. These are decent , hopefully sonarworks gives us a correction filter for us music producers
 

Zensō

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The frequency response is not bad all , you can fix that with like 2 eq filters , compared to the 6-8 filters you need for most refference headphones . Active headphones seem to be the go to for linear frequency response. The AKG N700 Nc is one of the flatest headphones out there . Too bad we dont have open backs for wireless active headphones. These are decent , hopefully sonarworks gives us a correction filter for us music producers
Agreed. I submitted a feature request asking Sonarworks to add this headphone, hopefully others have as well.
 

Gabe33

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Agreed. I submitted a feature request asking Sonarworks to add this headphone, hopefully others have as well.
Just submitted mine . Hope they get an accurate messurement, their recent headphone filters have been questionable . Oratory 1990 has a good filter on his site
 

Herbert

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This test was done using Windows sources and hardware? Reason why I am asking:
To my experience, from the Iphone4s on, Apple hardware recognizes what earphones are connected. When I soldered the cable of the 4s‘ in-ears to my Koss Porta Pro headphone, (built since 40 years btw) the Koss sounded shrill on the Iphone 4s, but balanced on the Iphone4. Bridging the chip in the cable where the talkback microphone sits removed the effect. So some hidden, undocumented EQ was kicking in in the background to compensate for the poor freqency response of the in-ears. Could be the same here…
 

staticV3

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This test was done using Windows sources and hardware? Reason why I am asking:
To my experience, from the Iphone4s on, Apple hardware recognizes what earphones are connected. When I soldered the cable of the 4s‘ in-ears to my Koss Porta Pro headphone, (built since 40 years btw) the Koss sounded shrill on the Iphone 4s, but balanced on the Iphone4. Bridging the chip in the cable where the talkback microphone sits removed the effect. So some hidden, undocumented EQ was kicking in in the background to compensate for the poor freqency response of the in-ears. Could be the same here…
That is not the case:
https://www.audiosciencereview.com/...-noise-cancelling-headphone.25609/post-873328
 

garbulky

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I'm quite surprised. I wasn't expecting a headphone that was wireless that was capable of such low distortion. Hopefully Apple would remap the eq for future iterations.
 

preload

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Allow me to clarify the issue with the curve. Nobody tells Apple what curve is correct. Apple tells you. The airpods max are not headphones for "people who like curves," they're for people who think differently. The airpods are for people who don't want to follow the crowd and are instead able to see past conventional sound theory. These are the listeners who are innovative and aren't afraid to be bold.
 

thewas

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True, Apple users are all cool unique individualists (but just millions of them and happen to camp in front of their stores waiting for the newest product from their Messias), not Harman curve fanboys who never had fun in their pathetic lives and dare to criticise hip companies Apple, B&W, Classé, Dynaudio etc. hiding behind their nerdy RGB keyboards.
 
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JoeBrooklyn

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I wonder whether the bluetooth performance would be better with a iPhone or Mac? Does Apple have any proprietary bluetooth tweaks?
 

MayaTlab

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I wonder whether the bluetooth performance would be better with a iPhone or Mac? Does Apple have any proprietary bluetooth tweaks?

On the Mac you can use Bluetooth Explorer to know which codec is used and with the APM it’s just 256kbps AAC. Supposedly Apple’s devices are pretty good at bluetooth AAC encoding while Soundguys found that some Android phones had crappy performances.
 

Somafunk

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Qualcomm has just announced lossless and high res over Bluetooth so I hope Apple has something up it’s sleeve

Qualcomm info here
 

MayaTlab

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I hope that they’ll actually ditch bluetooth altogether perhaps for something based on ultra wideband tech for example (there already are examples of audio over UWB, Audio Technica has a mic system using that technology for example).
Also, lossless on quite a few headphones is akin to polishing a turd IMO given the FR curves involved.
 

JJB70

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Apple have their audience, and their products clearly appeal to that audience. I would bet a tidy sum that nothing about this design happened by accident or just coalesced out of the ether. Because it doesn't conform to the Harman curve does not mean that it was not subject to a rational design process.
 
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