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Drop AKG K7XX Review (Headphone)

Robbo99999

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I'll agree to disagree. I honestly never understood this technique of putting lipstick on a pig, the so-called pairing approach of audiophilia. Premier quality equipment should get out of the way of the signal chain as much as possible, never requiring special distortions or radical shifts from natural response to conceal its flaws. Hearkening back to that era you speak of, the setups I heard that made the K701 sound "good" always sounded fuzzy, bloated and warm to me, obscuring inner recording detail. That to me bespeaks of a severe problem because when I am paying a substantial sum of money, I want to hear the source material sing and not the playback equipment ring. Thankfully, we are confirming here more and more here that retail price and series placement is most certainly not necessarily commensurate with real-world performance. I would gladly take one of AKG's cheaper studio headphones over this overrated mess.
I think it's important to put it into perspective - with EQ you can fix a lot of headphones, and certainly in my experience with my K702. Now, how Amir would measure & rate the K702 I'm not sure, and it's possible he would shoot it down, but that doesn't change it being a good experience for me. Whether or not this would have been the case if I had owned this K7XX that was tested I can't say......but EQ will fix out of the box tonality. Distortion measurements from Amir are pretty tough on the headphones, and are more extreme than my use cases, so I know for my listening levels & usage I really only need to focus on the 94dB line, and that would only be relevant for bass distortion for me, not the rest of the frequency range (unless major major defects at 94dB in other parts of frequency range).
 

xaviescacs

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I think it's important to put it into perspective - with EQ you can fix a lot of headphones, and certainly in my experience with my K702. Now, how Amir would measure & rate the K702 I'm not sure, and it's possible he would shoot it down, but that doesn't change it being a good experience for me. Whether or not this would have been the case if I had owned this K7XX that was tested I can't say......but EQ will fix out of the box tonality. Distortion measurements from Amir are pretty tough on the headphones, and are more extreme than my use cases, so I know for my listening levels & usage I really only need to focus on the 94dB line, and that would only be relevant for bass distortion for me, not the rest of the frequency range (unless major major defects at 94dB in other parts of frequency range).

Of course. Next thing to me is find out at what spl I usually listen to music, perhaps trying to find some peaks to get a better understanding, and then come back to the curves again. Thanks!
 

GWolfman

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I've considered these many times in the past, glad I didn't bite the bullet.

Anyone have the response curve from Drop to compare with what Amir measured?
 
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amirm

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Anyone have the response curve from Drop to compare with what Amir measured?
They have a measurement but I don't know what fixture they used:


MD-4505_20141120093610_c7ab26f4fef5600d.png
 

phoenixsong

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They have the K712 measurements too, doesn't look too different at a glance
 

Robbo99999

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Of course. Next thing to me is find out at what spl I usually listen to music, perhaps trying to find some peaks to get a better understanding, and then come back to the curves again. Thanks!
It's possible to work out by calculation what SPL you listen at for Peak RMS, I worked it out here:
https://www.audiosciencereview.com/...as-been-measured-by-oratory.22992/post-767745
You could do something similar, you ideally want to know the exact sensitivity of your individual headphone unit by having it measured, but (really in most cases) failing that you can use the factory spec for headphone sensitivity at 1kHz that the manufacturer lists for your model of headphone.....then you can go through the process I outlined in my post I linked. (You also need to know you max output of your DAC in volts)
 

Robbo99999

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bravomail

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The K7XX has a a good bass response that doesn’t sound rolled-off like many other K7** models. (excluding the K712 I reckon). Not suited for bass-heads.
Not suited to be driven directly from phones, tablets. It may not play impressively/loud enough.
Higher end DAPs (with a higher output voltage) and desktop gear is what’s required for this headphone.

K7xx out of the box lacks some bass. Luckily, there is a "bass mod". Very simple - involves removing a sticky piece of paper in the center of the driver.
Ye, and I agree with not driveable by mobile (tablets, phones) - mine driven by Schiit Magni3 or Topping L30. Fuller sound.
That springy support lines do wear out, and headset feels flimsy. I could care less - I'm not running in those.
My use case - general audio and gaming - because staging and stereo base r really good.
As for high distortion - it is probably there if you drive it to high ear-piercing volumes. At normal level - I hear no distortion.
Thx, Amir! Your measurements are good, but us, fans/owners of AKG K7xx are hardcore! :)
 

solderdude

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The bass port mod is f'ing up distortion numbers.
Below the effect of the bass mod on the K702 regarding frequency response
eq.png
.

Below the situation above but the distortion levels at the exact same volume (90dB SPL)

stock distortion (90dB SPL) followed by K702 + EQ (same EQ as the bass mod would bring) followed by the bassport mod.
dist-port.gif

Let's just say that AKG used damping materials on the rear of the magnet for a reason.
 
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tifune

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Ouch...do you have a k712 PRO put aside for later review @amirm ? I suspect it might (just might) perform better.

I have a pair I can submit, but I modded them to make them balanced so I'm not sure it's a great representation of their design. @amirm PM me if you're interested? They're the most comfortable open-backs I've personally used, but as far as sound quality the HD650 can be had for similar price on the secondhand market
 

welsh

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Ooo, On the Waterfront! Excellent film, excellent director, superb actor and superb musical score. Strongly recommended!
I remain convinced that Brando had a contract clause that ensured that his character be beaten to a pulp… see also The Wild One.
 

welsh

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For one, the sense of space is real and enjoyable in the K7-- series. I'm also guessing that DACs and amps in the past were less resolving and came with their own problems, so with certain pairings the series can actually sound really good relatively. I remember at least 6-9 years back (forgot the exact timing) equipment pairing was a major thing
I had the white Quincey Jones? endorsed Q701 (still made in Austria when I bought them). Believing the Head-Fi hype, I bought the Heed CanAmp - which was supposed to enjoy ‘magical synergy’ with the AKGs. It had, I seem to remember, a 120 Ohm output impedance, and featured a single transistor per channel. A thin, bassless and sibilant mess…
 

NoSnakeOil2

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Note: a horizontal line is 'audible flat' acc. to me. The dip around 4kHz isn't as deep in reality and the resonances above 10kHz will be smaller in reality due to a pinna-less measurement.

K702 fitted with K7XX pads vs K7XX

k7xx-pu-vs-k702-with-k7xx-pads.png


K702 is slightly more damped.

For completeness K712 vs K7XX
k712-bn-vs-k7xx-gn.png


my conclusion:

The K7XX has a a good bass response that doesn’t sound rolled-off like many other K7** models. (excluding the K712 I reckon). Not suited for bass-heads.
Treble and upper mids are much better in balance than most other K7** models.
The sound is warm and full with tight and not emphasized nor colored bass.
Mids are a tad on the ‘laid back’ side of things but not as much as the K712.
Treble quality is not on par with that of the bass and mids, the K712 is slightly better in this department and sounds a bit ‘smoother’.
The K7XX is a bit coarse/grainy as in not ‘smooth, silky’ like TOTL headphones often show.
Those that find the HD58X, HD650 etc. too ‘forward’ may find the K7XX a nicer sounding option… but with less refined treble.
The treble amount is good though so no harsh or shrill mids anywhere.
Not suited to be driven directly from phones, tablets. It may not play impressively/loud enough.
Higher end DAPs (with a higher output voltage) and desktop gear is what’s required for this headphone.


I've had the AKG712s for about a month, and I really like them, primarily for the comfort. I've become tired of headphones that measure well but hurt after 40 minutes of use. I use a V-ish EQ, and I've rarely felt the mids or vocals sounded distorted, but maybe I haven't had enough experience with headphones, and/or my 50+ year old ears, to know the difference. I much prefer the 712s to my Sennheiser 6XXs, which just sound "blah" to me, even with EQ.

I really like headphones that show micro-details (real details, not details artificially created by extreme treble EQ boost). I know Amir recommended the Dan Clark Audio RTs, but then I see/read several reviews that say, "yeah, they are good, but I don't listen to them much compared my Sundaras or my Senns because they are dullish". Any suggestions? thanks.
 

xaviescacs

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It's possible to work out by calculation what SPL you listen at for Peak RMS, I worked it out here:
https://www.audiosciencereview.com/...as-been-measured-by-oratory.22992/post-767745
You could do something similar, you ideally want to know the exact sensitivity of your individual headphone unit by having it measured, but (really in most cases) failing that you can use the factory spec for headphone sensitivity at 1kHz that the manufacturer lists for your model of headphone.....then you can go through the process I outlined in my post I linked. (You also need to know you max output of your DAC in volts)

Thanks!! When do you say DAC I assume you mean headphone amplifier. If I understand correctly, the maximum voltage level would give the maximum spl possible. Is that correct? The maximum output voltage of my headphone amplifier is 7 V RMS, given by the manufacturer. The issue is that it has a gain setting and I have it half the way (3.5 V RMS? xD). If I set it to the maximum, I would need to set the volume knob at less tan 1/4 or so. I guess this is the result of the combination that I don't listen very loud (well, that's what I want to find out) and the amplifier has a lot of power.

I don't know how naive is this, but to have an idea of the spl I thought I could hear a some generated tone or tones, up to a reasonable volume, and then measure the output voltage with a simple multimeter.

In any case, I will try to refresh some of this electrical and sound concepts and come back to the issue. It's difficult to me to use the calculator without knowing what is doing. Thanks again!
 
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amirm

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I have a pair I can submit, but I modded them to make them balanced so I'm not sure it's a great representation of their design.
Balanced wiring doesn't change the response. So if that is the only change, then yes, let's test it.
 
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amirm

amirm

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I really like headphones that show micro-details (real details, not details artificially created by extreme treble EQ boost). I know Amir recommended the Dan Clark Audio RTs, but then I see/read several reviews that say, "yeah, they are good, but I don't listen to them much compared my Sundaras or my Senns because they are dullish". Any suggestions? thanks.
You have to EQ them to sound exciting.
 

solderdude

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Any suggestions? thanks.

The problem is that a headphone I or someone else really likes someone else or you may not like. For this reason my advice would be to audition headphones. I have a few AKG's and owned and sold/returned others. They don't do it for me.
Haven't heard nor measured the latest and updated hifimans the last 2 years or so. chances are they sound better than the older versions.

Personally I look for headphones that sound fine without EQ or that just need minor corrections. Here too... what I like others may not.
 
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