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Understanding Headphone Measurements & Hifiman HE-6 Review (video)

amirm

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#1

DualTriode

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#2
@amirm,

Thanks for the headphone review video.

I also have a GRAS 45CA Hammer on my bench. I find that the APx555 cooling fan noise creeps into my measurements unless I use long cords and place the 45CA a relative long distance away from the fan noise.

Please share what you you do do to minimize ambient noise in your headphone measurements?

Thanks DT
 
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#3
Great explanation, well thought out delivery and clear communication. I honestly feel like you have a talent for explaining this stuff to people in a manner that the average joe will understand. As an IT person I know, regardless of knowledge, this doesn’t always come easy. Thank you for what you do!
 

Robbo99999

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#4
This is a detailed walk-through of my headphone review and measurements in the context of Hifiman HE-6 headphone. By definition is rather long but you can watch it faster than real-time and slow down where needed:


Text review of Hifiman HE-6: https://www.audiosciencereview.com/forum/index.php?threads/hifiman-he-6-review-headphone.21673/
Hi Amir, that's the first video I've seen of yours, as I don't often watch video reviews on any sites, but it was a good way to get a deep dive on your approach. It's a good combination of approaches you have I think, I have a slightly different take on what I think is the best EQ approach (even though I am a Headphone Harman Curve fan) but that doesn't need to be discussed in this post. I also learned a few technical points from your vid, so yeah good vid & good explanations, and I'll watch some more of yours in the future rather than just reading the reviews....I'll read the reviews first and then if I want to know more I'll watch your vids. Nice one!
 
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da Choge

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#6
Have to agree with all the preceding comments - one of my favorite video reviews thus far and I learned a lot to boot! Hopefully this kind of stuff will quiet those critics that say listening isn't important to ASR followers. Excellent!
 

ezra_s

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#8
Another 44 minute video that felt sort! Great job.
 
OP
amirm

amirm

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Thread Starter #10
Appreciate the kind remarks you all. As the timer ticked to 40+ minutes, I got concerned that it had gone too long. Glad to hear it was still watchable.
 
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#12
Don’t worry about the length, Amirm. As far as it is full of well presented knowledge (as it is obviously the case not only here), the attention is well held. As far as it’s not over hour and half we’re good. /That would be when students usually require a break - at least from my university experience :)/
 

phoenixsong

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#14
Indeed, if anything I am grateful for this chance to be educated (if ever so slightly) on this topic. As a current undergraduate student I have gained a whole new level of appreciation towards people who take the time and effort to share precious knowledge without the incurrence of financial liabilities :p
Not to mention that this will be really helpful in an area of interest to me :)
 
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#15
HP measurements:
One I'd missed, is isolation from outside noise. That's not a difficult one to test. As most HP tested on this site are not NC type, this might add a layer.
I've mentioned comfort already. It's a must. Maybe comes even B4 sound...
As we do not expect a flat response, A ref. curve is good enough.
On reproducing devices, more listening test would do. It's kind of missing from this very technical topic. After all, this is what it's all about.
I'know, This site is all about measurement. Well, I had some gear that measured fantastically, sounded mediocre. Never judge a peace of equipment
by measurement only. You must listen to it too. I'm sure you all do, but this site...
 
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amirm

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Thread Starter #16
HP measurements:
One I'd missed, is isolation from outside noise. That's not a difficult one to test.
It is for me as you have to have a quiet chamber and I just don't have the space for a giant coffin!
 
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amirm

amirm

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Thread Starter #17
I'know, This site is all about measurement.
You just watched a video which talked extensively about listening tests, yet decided to repeat this myth about us???
 
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#18
It is for me as you have to have a quiet chamber and I just don't have the space for a giant coffin!
It can be done with less finess. Run a measuring sweep of the audio band while playing some white noise at the background, in your lab.
Get a pair of speakers. make one directional and the other not. Play it and set the bar of readings, to 0 dB.
Return the test with the HP on the test bench.
The delta noise @ Fr. is the noise attenuation of the HP. (the -x dB = to HP attenuation.

A quiet chamber is nice to have, but it is not necessary for such a test. Just saying that this information is also practical.
 

bluefuzz

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#19
By definition is rather long
Length is no problem as long as the content is interesting - which, as usual, it is.

One small point. You stated at one point that The MiniDSP EARS has hard pinna and is therefore less accurate. The silicone pinna on mine are very lifelike and squishy. I'd judge them slightly softer than my own ears. They compress fine under the pressure of an on-ear headphone ...
 

DualTriode

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#20
For grins I set up a pair of calibrated GRAS 40AG microphones; one on the bench next to the APx555 and APx1701 with cooling fans running. The 2nd microphone was set up across the hall in a bedroom with two closed doors in between.

The ambient noise was significantly lower across the hall from the instrument fans.

Thanks DT

FFT GRAS 40AG microphones.png
RMS Noise Level across the hall behind 2 closed doors.PNG
 
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