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AKG K702: a valid alternative EQ to Harman Curve for you to try

roladyzator

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I have a 7000 Hz peak on my K702. I reduce it with a filter with Q=5 and gain of -4.

Starting with Oratory1990's PDF, I don't use the 50 Hz filter and leave a little more upper bass (the 210 Hz filter). Less negative gain for 2.3 kHz and 5.5 kHz. I don't activate the 3.5 kHz - it makes them somewhat more fatiguing for me.

Compared to Oratory1990 equalized Sennheiser HD700, they sound similar but somehow more laid back yet more fatiguing with certain sounds. I probably can't get the upper mids and treble right.

They're made in China and IIRC the serial number was starting with 217.

If they were more consistent they would be such an obvious recommendation. In Poland you can buy almost two of these for the price of HD600, Sundara and the like.
 
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Robbo99999

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I have a 7000 Hz peak on my K702. I reduce it with a filter with Q=5 and gain of -4.

Starting with Oratory1990's PDF, I don't use the 50 Hz filter and leave a little more upper bass (the 210 Hz filter). Less negative gain for 2.3 kHz and 5.5 kHz. I don't activate the 3.5 kHz - it makes them somewhat more fatiguing for me.

Compared to Oratory1990 equalized Sennheiser HD700, they sound similar but somehow more laid back yet more fatiguing with certain sounds. I probably can't get the upper mids and treble right.

They're made in China and IIRC the serial number was starting with 217.

If they were more consistent they would be such an obvious recommendation. In Poland you can buy almost two of these for the price of HD600, Sundara and the like.
That's pretty interesting that you have a peak at 7000Hz too, which doesn't appear in my measurements, nor Oratory's, nor Crinacle's.....and therefore I had thought that my 7000Hz peak would therefore just be a quirk of the headphone on my own head, but you have a peak there too, interesting. I haven't checked my other units though, in terms of hearing a 7000Hz peak, I've just checked my 4th unit, I could potentially check my other 3 units. I had also wondered if it might just be down to headphone placement, and perhaps it would change if I removed and then reseated the headphone, but I didn't check that. I haven't experimented yet with what EQ filter would be required to remove the 7000Hz peak.

Your headphone starting at 217 for the production number (probably 217000), means that would place yours between my 3rd & 4th unit in terms of age. Both of those purchased through Amazon UK, 3rd unit purchased beginning of last year and 4th unit purchased beginning of this year (if I remember rightly for both of them).

EDIT: checked on my 3rd unit of K702 by listening to sine tones, it also has the peak at 5000Hz albeit to a lesser extent than my 4th unit of K702, which is reflected in my measurements between them too. 3rd unit also has the peak at 7000Hz that does not appear in measurements, but again to a lesser extent than unit #4. My third unit has new aftermarket pads that mimic the same design as the originals, I've proven in past measurements that they only differ slightly than stock pads (potentially imperceptibly). The 4th unit is using new stock pads (recently bought headphone).

So I'm totally confident that Crinacle's measurement is not representative of my 4 units of K702 - they all have noticeable peaks at 5000Hz whereas Crinacle's measurement is showing no peak at 5000Hz.
 
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roladyzator

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I did some casual listening today with my K702 S/N: 214079 (I said it was 217XXX previously, that was an error on my side).

Current Oratory1990's preset taken at face value results in a bright K702 for me. Clearing up the shouty mids alone makes them more listenable and the bass boost is a welcome addition. However, I don't like the ~210 Hz reduction of -3.6 dB, it makes the bass kind of disappear behind the rest of the music. Increasing the bass shelf more does not compensate for this. I don't think I need the 3.5 kHz filter as well.

Robbo's EQ: I welcome the additional warmth and not reducing that much in the 200 Hz region. Bass sounds nice and full. Treble level is reduced in general. Besides sounding a little too warm and "bloomy" at times, this is a good way to listen to my K702.

My personal favorite is a bass shelf and -4 dB filter at 2.3 kHz from Oratory1990's PDF. While the shoutiness in the mids is not completely gone, it's not terrible and it's balanced out by the extra bass.

My K702 have a treble peak at 7 kHz and reducing it with a narrow peak filter does clean up the sound a little, but I'm not 100% sold on it. Sometimes leaving the stock sound in the upper treble just sounds better to me in tracks with less sibilance.

There was also Sonarworks correction but I haven't listened to that in a while. From memory, it sounded too dark, but certainly fine after some adjustment time. Just a little unexciting.
I did capture the FR of that correction so I may paste it here for reference.
 
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Robbo99999

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I did some casual listening today with my K702 S/N: 214079 (I said it was 217XXX previously, that was an error on my side).

Current Oratory1990's preset taken at face value results in a bright K702 for me. Clearing up the shouty mids alone makes them more listenable and the bass boost is a welcome addition. However, I don't like the ~210 Hz reduction of -3.6 dB, it makes the bass kind of disappear behind the rest of the music. Increasing the bass shelf more does not compensate for this. I don't think I need the 3.5 kHz filter as well.

Robbo's EQ: I welcome the additional warmth and not reducing that much in the 200 Hz region. Bass sounds nice and full. Treble level is reduced in general. Besides sounding a little too warm and "bloomy" at times, this is a good way to listen to my K702.

My personal favorite is a bass shelf and -4 dB filter at 2.3 kHz from Oratory1990's PDF. While the shoutiness in the mids is not completely gone, it's not terrible and it's balanced out by the extra bass.

My K702 have a treble peak at 7 kHz and reducing it with a narrow peak filter does clean up the sound a little, but I'm not 100% sold on it. Sometimes leaving the stock sound in the upper treble just sounds better to me in tracks with less sibilance.

There was also Sonarworks correction but I haven't listened to that in a while. From memory, it sounded too dark, but certainly fine after some adjustment time. Just a little unexciting.
I did capture the FR of that correction so I may paste it here for reference.
Oratory's latest EQ's for K702 sound too bright for me too, so we've got that in common. They'll always be some unit to unit variation combined with personal taste. Appreciate the feedback on my EQ - again unit to unit variation & personal taste, but seems like you notice an improvement.

EDIT: I run my HD560s headphones on a slightly darker EQ than Oratory's too. But for my HE4XX and NAD HP50 I would run an Oratory EQ unaltered, so it's not the same for each headphone.
 

roladyzator

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I've loaded yours, Oratory1990's and Sonarworks EQ curves into REW.

I used 1 kHz as the alignment point (not great but had to go with something).

k702 eq comparison.png
 
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Robbo99999

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I've loaded yours, Oratory1990's and Sonarworks EQ curves into REW.

I used 1 kHz as the alignment point (not great but had to go with something).

View attachment 284217
Interesting. I can't vouch for the accuracy of your graph (as I'm not gonna check it), but I'll assume it's valid & accurate - certainly it's showing my EQ is darker than Oratory's which is what I already knew & have mentioned. There's general similarities between all of them in terms of dips & peaks, and certainly between my own & Oratory's EQ (which is to be expected), just different slants mainly.
 

Dazerdoreal

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Ok then, as long as you're aware of the difficulties/pitfalls re listening to sine sweeps/tones. What do you mean re Solderdude's measurement? It certainly looks different because it's done on a flat plate, or do you mean something else?
I made some tests and now I am quite sure it all depends on how I wear them. Depending on how the pads are angled towards my ear the focus shifts from 5,5k to 7k.

So, I found a position where your EQ probably would sound about "right", it is just not my standard way. I would have to wear them in front of my head and the headphone tilted backwards. Then I can hear the 5,5k peak clearly. If I do it the other way round I hear the peak at 7k.
 
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Robbo99999

Robbo99999

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I made some tests and now I am quite sure it all depends on how I wear them. Depending on how the pads are angled towards my ear the focus shifts from 5,5k to 7k.

So, I found a position where your EQ probably would sound about "right", it is just not my standard way. I would have to wear them in front of my head and the headphone tilted backwards. Then I can hear the 5,5k peak clearly. If I do it the other way round I hear the peak at 7k.
Interesting. K702 is the one headphone of mine that I've done extreme placement measuring on my miniDSP EARS (not for this particular EQ project), and it didn't vary much which led me to revise my headphone measuring procedure to be roughly central through multiple reseats. Perhaps it can have those larger variances though with placement on real heads vs a flat cheek fixture. Oratory's K702 measurements show the 5.5kHz peak, but not the 7kHz peak (so my measurements also show the same trend, as it's based off his initial measurement of one of my units). K701 (and by extension K702) doesn't have large variation on real human heads though (blocked ear canal measurements) from some data I've seen, can't find the graph now, might have even been Harman research (can't remember). Found the post where I found the graph, but unsure it's source (& in that thread where this was posted MayaTlab user said he thought these graphs stop at 2kHz, so it wouldn't cover the 5.5kHz to 7kHz are that you're talking about):
index.php


I wear my own K702 just in a way that creates the least number of feelable contact points on my ear, I can just about see the front of each earcup out of the corner of my eye when I look left & right (but that will vary on how big your face is, lol). A lot of the times with my various headphones I'll try to wear them as far forward as I can, ie just to the point that the rear of my ear is no longer touching the back of the inside earcup pad. Generally there's not masses of space in headphone earcups so my method of wearing them is probably reasonably central.
 

roladyzator

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Testing with pink noise, moving K702 on my head results in changes in the brightness.
The sound is the brightest when I imagine me year is in the center or the front part of the earcup (that is, the front of my ear is closer to the front side of the earcup).
When I move the earcups so that the rear of my ears start touching the rear side of the cups, I get noticeably darker sound.
It gets even darker when I continue to move the earcup until it starts deforming my ears.
 

roladyzator

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I created a 10 filter EQ approximation of SoundID equalization using AutoEQ and minor custom adjustments.
Feel free to try that as an alternative.

soundid_filters.png
 

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markanini

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Testing with pink noise, moving K702 on my head results in changes in the brightness.
The sound is the brightest when I imagine me year is in the center or the front part of the earcup (that is, the front of my ear is closer to the front side of the earcup).
When I move the earcups so that the rear of my ears start touching the rear side of the cups, I get noticeably darker sound.
It gets even darker when I continue to move the earcup until it starts deforming my ears.
I noticed something similar on AKG K612, which shares some internal design aspects.

BTW a popular tweak on Harman correction EQ is boosting upper-bass and reducing upper-mids lightly, Oratory1990 personally uses something like this.
https://www.reddit.com/r/oratory1990/comments/ii25sl/_/g38a7ri
 
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