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End Game Headphones

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bigcrunch

bigcrunch

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There's a long and somewhat painful thread about group delay you can search for. Group delay is how quickly the phase angle changes with frequency (i.e. the derivative of phase wrt frequency). So a positive group delay means the phase is increasing wrt to frequency. A negative value means the phase is decreasing wrt to frequency.

If the plot of group delay is centered around some value (e.g. 0), it means the phase angle is oscillating around some constant.
Thanks for explaining that. The plot makes much more sense now that I know that it's the derivative with respect to frequency. I will see if I can track down that thread you mentioned to learn more about this...
 

Ata

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IIRC the headphone driver itself is a minimum phase device, thus with a very good group delay. The group delays we measure are basically sound interactions between the driver and the cup, little frequency dependent sound wave reflections and resonances that result in these deviations. For the lack of a better description, I think of it as a different acoustic signature inherent in the overall design, which subtly changes the sound and our perception of it.
 
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bigcrunch

bigcrunch

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IIRC the headphone driver itself is a minimum phase device, thus with a very good group delay. The group delays we measure are basically sound interactions between the driver and the cup, little frequency dependent sound wave reflections and resonances that result in these deviations. For the lack of a better description, I think of it as a different acoustic signature inherent in the overall design, which subtly changes the sound and our perception of it.
Interesting. It's a bit of a crapshoot, but in that case, do you think it might be possible to alter/improve the group delay with mods (e.g. additional dampening inside the cup)? I guess even if it was possible, it would require a lot of trial and error, and you would need a way to measure the effect that your mods have on the sound signature to know if they are improving it or not, but it might be interesting to try if there is a theoretical basis for it.
 
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radix

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Interesting. It's a bit of a crapshoot, but in that case, do you think it might be possible to alter/improve the group delay with mods (e.g. additional dampening inside the cup)? I guess even if it was possible, it would require a lot of trial and error, and you would need a way to measure the effect that your mods have on the sound signature to know if they are improving it or not, but it might be interesting to try if there is a theoretical basis for it.
I think one of the main things Amir looks for in the group delay is swings that might indicate the designer purposefully cut a frequency, such as to avoid a resonance. That's what's going on in post #12 where he says "don't EQ." He thinks that GD swing around 10 kHz corresponding to a FR dip is on purpose.

Personally, I think the designers for mid- to high-end headphones know about all this stuff and if there was a simple way to fix it without making bad tradeoffs, they would have done it. There's usually some Pareto front where you cannot improve one thing without worsening something else.

You could look at these posts



I'm not sure how the picture is different (if it is) for headphones vs speakers.
 

etc6849

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Benchmark DAC3 B -> HPA4 -> AHB2 x2 in mono -> iFi iESL electrostatic energizer -> Stax SR-X9000 (new flagship).
By far the best headphones I've ever heard or owned. I am totally blown away; I've owned many flagship headphones before tri-amping my home theater and giving up on headphones altogether. Finally I can saw I have headphones to match my main system :D
 

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FrantzM

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Hi

AN early session with my new toy and goto and likely endgame Headphones. Long story shortened here. I had the original HE6. It was used with a Yamaha CA-1000 and a speaker to headphones adapter. I used the vintage CA-1000 on Class A, A great amplifier that can be switched to work on Class A , at a substantial reduction in output , 25 wpc max. Great combo but energy inefficient, the amplifier would consume around 500 watts on Class A and heat like a furnace ... I used the Atom but it was barely adequate for ... I came to use an HifiMan HE560, mostly ... then you People! :D, had me look into the Hifiman HESEv2. I got it for around $499.00. The first sample was DOA, (of course would say the negative people, this is a rather alarmingly recurring problem of DOA samples from Adorama.... So yes! My first sample came DOA, with torn membrane on the left side. Communicated with HifiMan and they promptly sent me a new unit and ...
The hobby is full of hyperboles. I will refrain from using these , especially the often used "bargain" but the chain I presently have for my headphones system verges on the superlative, yet doesn't cost a lot. Not often does one get SOTA for relatively modest cash outlay... An endgame system for this amount of money, tend to be called that .. Ok Pas cher. :D.

Raspberry Pi as a streamer and EQ.$100
Khadas Tone Board for DAC, Soon to be replaced for convenience by a Topping D10$100
Drop THX AAA789 Amplifier$150
HifiMan HE6SEvw$500
Total$850.oo

Top flight, by any metrics, be these objective or subjective. SINAD? Top of the Class. Bass extension? Out of this World. FR Linearity, once EQ and this headphones can take a absurd leve of EQ... THD for the transducers? What does 0.1 % or less across most of the audible spectrum sounds like ? :) All that for less than $1 K. Some people would utter the dread "barg.... " word. I won't :D
I would encourage those who are into headphones to consider or at least audition it , if they can.


Peace.
 
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