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PSB M4U 1 Review (headphone)

maverickronin

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#21
Best THD I've ever seen. Unbelievable. From a dynamic driver to boot, just wow.

No excuse for anyone out there. Sennheiser especially now that I think about it.
The low bass distortion is easier in a closed design though so it's not really a fair comparison.
 

3125b

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#22
Best THD I've ever seen.
Put A-weighting on it, and it's not that good. Granted, at the most realistic 94dBSPL level it's fine, but so are most headphones. A few percent of distortion in the subbass don't matter too much, in the 2-6kHz region, where the hearing is much more sensitive, there are two peaks.
 
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Robbo99999

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#25

Spocko

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#26
Best THD I've ever seen. Unbelievable. From a dynamic driver to boot, just wow.

No excuse for anyone out there. Sennheiser especially now that I think about it.
And thus Sennheiser has given up the consumer market entirely and is trying to find a buyer for that subsidiary.
 

Joachim Herbert

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#27
Wonder how these would measure with news pads. The ones in the picture are worn out.
 

Robbo99999

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#28
Wonder how these would measure with news pads. The ones in the picture are worn out.
It's true that new pads vs worn pads will change the frequency response, but my how much & how quickly pads become "worn" is another question too. For instance, Oratory when he measures headphones sometimes measures worn vs fresh pads....in fact I sent off my K702 to him yesterday along with some fresh pads, so he'll be adding K702 worn vs fresh pads.....which is useful because you can have 2 different EQ's hopefully reflecting the useful life of your headphone more accurately.
 

3125b

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#31
The HD 820 has low distortion at least at 90dBSPL, but also a terrible case of closed-back-bass, Crinacle simply said:
"The mystical acoustic properties of Gorilla Glass could not save this monstrosity."
The bumpy bass is something usually seen in older and cheaper closed back headphones, but for 2400$ Sennheiser should have done a lot better:
HD820-1536x689.jpg Audio Technica ATH-M50X Measurements Frequency Response closed headphone.png Beyerdynamic DT 770 250 Ohm.png
There's one graph in every flavour :)

That being said, it could always be worse I guess:
Ultrasone DJ 1 Pro.png
Where would you even start EQing the thing? The algorithm can't make sense of it either it seems.
 

maverickronin

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#32
Hopefully that will then translate well if and when the HD820 crosses Amir's bench, I better not see any distortion higher than this headphone.
I think you'll probably be disappointed on that front too. I'm sure they could have have made it very clean in the bass I doubt they did given the care they put into tuning the FR.

I think their design goals began and ended with, "A closed headphone that also has soundstage". It's a lot of unfulfilled potential.

I still want one though. No closed back in production matches the soundstage.
 

Tks

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#33
I think you'll probably be disappointed on that front too. I'm sure they could have have made it very clean in the bass I doubt they did given the care they put into tuning the FR.

I think their design goals began and ended with, "A closed headphone that also has soundstage". It's a lot of unfulfilled potential.

I still want one though. No closed back in production matches the soundstage.
Pretty pathetic would be what I was hinting at.

As far as "soundstage". If this industry wasn't braindead, they would take a hint and copy some of the housing design of the HD800 itself (I don't understand why no one will take this hint, and realize how such a spacious design does most of the "soundstage" work, more so than that failure of a driver design they've got going). With enough of a similar housing design, and EQ, you could easily get this "soundstage". I would wager almost anything, that if you were to transplant an HD650 driver, into a H800-style housing, you would get a similar-enough sensation, and basically an indistinguishable enough sensation if you EQ'd it especially.

But I can't expect much from an industry that can't even get ergonomics right in the majority of headphones (whether due to stupid pads that depress inadequately, or due to inherent design choises where you have to have an ear of an infant to properly fit in the cups and not have anything touch).
 

restorer-john

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#34
Can you set it up flat and have someone do a/b? Since it's obviously not as good, lets have a friendly wager to see if you can tell which signal is which out of ten tries.
The old EQs can always be picked by the increase in residual noise when switched in. ABX in the middle of a loud musical track, not so much.
 

maverickronin

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#35
As far as "soundstage". If this industry wasn't braindead, they would take a hint and copy some of the housing design of the HD800 itself (I don't understand why no one will take this hint, and realize how such a spacious design does most of the "soundstage" work, more so than that failure of a driver design they've got going). With enough of a similar housing design, and EQ, you could easily get this "soundstage". I would wager almost anything, that if you were to transplant an HD650 driver, into a H800-style housing, you would get a similar-enough sensation, and basically an indistinguishable enough sensation if you EQ'd it especially.
Yeah, it's in the angle, distance openness, and also the larger driver. I don't think that throwing an HD650 driver in there would work as well though.

It's flat out touching your ear in the HD650 chassis. Move it out 3/4 of an inch, increase the volume on the ear side by several times, and get rid of almost all the damping and you'll probably be asking it to move too much air.

You right it's not magic though, and there's not really any reason they need to be so expensive other than the fact that they can get away with it...
 

bobbooo

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#36
As noted elsewhere the more current and full featured PSB M4U-8 is a real Harman curve hugger. Gets mixed reviews re build quality but mine haven't broke yet.
View attachment 118504
Even closer to the Harman target in the sub/lower-bass with ANC on (although mid/upper-bass gets a bit over-boosted):

Screenshot_20210316-212836_Acrobat for Samsung.png
 
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pjug

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#37
Even closer to the Harman target in the sub/lower-bass with ANC on (although mid/upper-bass gets a bit over-boosted):

View attachment 118572
Would M4U-2 be expected to be similar? I bought these on Drop for $100 or something like that. Just because I wanted ANC for air travel, I'm not really a headphone person.
edit: I see the M4U-8 has DSP. Probably M4U-2 is more like M4U-1.
 
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Chromatischism

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#38
Best THD I've ever seen. Unbelievable. From a dynamic driver to boot, just wow.

No excuse for anyone out there. Sennheiser especially now that I think about it.
But no measurement of THD after EQ, so we don't have the full picture and it can't be compared to other headphones with such a curve already baked in.
 

Robbo99999

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#39
But no measurement of THD after EQ, so we don't have the full picture and it can't be compared to other headphones with such a curve already baked in.
You can estimate what it would be in the various boosted frequency areas from interpreting the distortion graphs Amir does at different SPL levels.
 

solderdude

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#40

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