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AKG K712 Pro Review (Headphone)
- Thread starter amirm
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That's because they are, K702, K712 but one could also say the K712 has a lot less clarity and treble than the K702 (and 701)
Either I'm going daft or your labels are swapped. Green is bassier than Red. Red is K712. @vhild§ says his K712 is bassier than K702 and you agreed. Brain melt!
EDIT- I am in idiot- see @staticV3 reasoned response below- look at proportionality of the whole FR rather than absolute level in one area of the FR.
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staticV3
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In this graph, red has the same bass as green, but less mids and highs.
That's the same as having more bass.
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Good point, I was looking at red being marginally lower on the left hand side but of course the big difference is on the right hand side- bass proportionally higher on red, gotcha.
Leiker535
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This headphone is an odd one for me. I seriously considered getting them used down here for gaming. But in that I also considered their musicality-all-rounder praise in the local community and reviews, which compare them directly to the 6xx/600 and the Beyerdinamics. Seeing these measurements (and rtings) I can attest more to their spatial qualities for gaming, but am made very skeptical about the SQ itself.
The dip on presence region would throw me off instantly. Oratory EQs and measures seem to indicate this headphone EQs nicely. But strangely, the dekoni sheepskin seems to adhere better to Harman than the overpriced stock pads:
Unfortunately he doesn't include distortion, resonance and group delay measures, so we can't be certain it doesn't get funky in spite of the great final FR curve.
The dip on presence region would throw me off instantly. Oratory EQs and measures seem to indicate this headphone EQs nicely. But strangely, the dekoni sheepskin seems to adhere better to Harman than the overpriced stock pads:
Unfortunately he doesn't include distortion, resonance and group delay measures, so we can't be certain it doesn't get funky in spite of the great final FR curve.
solderdude
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#blessed
yes, ideally both new, straight out of the box.
but then again age will become a factor, pads degrade over time...
not very realistic it would happen though since Austrian models are not made or sold anymore and NOS are very rare and expensive, so I'd be happy with a test with same pads swapped over from one to another.
btw I have a pair of Austrian AKG K240M, which I bought as NOS and part of the 1/4 adapter got stuck in my amp
had to take it out with tweezers.
the plastic degraded so much, even though the headphones are probably just ~20 years old or something around that, don't really know when AKG stopped making them.
Maiky76
Senior Member
Hi,
Here are some thoughts about the EQ.
Notes about the EQ design:
- The average L/R is used to calculate the score.
- The resolution is 12 points per octave interpolated from the raw data (provided by @amirm)
- A Genetic Algorithm is used to optimize the EQ.
- The EQ Score is designed to MAXIMIZE the Score WHILE fitting the Harman target curve with a fixed complexity.
This will avoid weird results if one only optimizes for the Score.
It will probably flatten the Error regression doing so, the tonal balance should be more neutral. - The EQs are starting point and may require tuning (certainly at LF).
- The range around and above 10kHz is usually not EQed unless smooth enough to do so.
- I am using PEQ (PK) as from my experience the definition is more consistent across different DSP/platform implementations than shelves.
- With some HP/amp combo the boosts and preamp gain need to be carefully considered to avoid issues
- Not all units of the same product are made equal. The EQ is based on the measurements of a single unit.
- YMMV with regards to the very unit you are trying this EQ on.
Good L/R match.
Default Harman curve
I have generated one EQ, the APO config file is attached.
Score no EQ: 54.9
Score Armirm: 75.3
Score with EQ: 75.6
Code:
AKG K712 Pro APO EQ [email protected] 96000Hz
November262021-145741
Preamp: -8 dB
Filter 1: ON PK Fc 29.06 Hz Gain 7.97 dB Q 0.42
Filter 2: ON PK Fc 242.76 Hz Gain -1.46 dB Q 0.86
Filter 3: ON PK Fc 1375.69 Hz Gain 6.72 dB Q 1.20
Filter 4: ON PK Fc 2093.36 Hz Gain -3.69 dB Q 2.62
Filter 5: ON PK Fc 3621.65 Hz Gain 7.52 dB Q 1.35Default Harman curve [email protected] HF (still within taste)
I have generated one EQ, the APO config file is attached.
Score no EQ: 65.2
Score Armirm: 80.5
Score with EQ: 84.1
Code:
AKG K712 Pro APO EQ [email protected] 96000Hz
November262021-150905
Preamp: -10.9 dB
Filter 1: ON PK Fc 23.70 Hz Gain 9.60 dB Q 0.42
Filter 2: ON PK Fc 254.34 Hz Gain -1.44 dB Q 1.21
Filter 3: ON PK Fc 1359.96 Hz Gain 5.11 dB Q 1.13
Filter 4: ON PK Fc 2203.86 Hz Gain -6.31 dB Q 2.58
Filter 5: ON PK Fc 3575.95 Hz Gain 11.49 dB Q 1.50
Filter 6: ON PK Fc 5976.71 Hz Gain -3.86 dB Q 2.54
A couple of things, your second EQ is using a different target curve to Harman whereas your first EQ is using Harman - you're not making it clear enough that you're using two different targets. Your second EQ has a lower target between 3-4kHz. Please make it clear that you're not EQ'ing to the Harman Curve, as it's not obvious from your post. Also, why are you introducing somekind of weird new target that is not Harman - that's very misleading and no basis for that.
Secondly, you could have easily boosted the frequency response in both EQ's to match the target, as the stock measured frequency response does not have nasty sharp dips or peaks, so your first EQ could so easily hit the Harman Target between 3-6kHz.....you're losing out a lot by not boosting that and filling out that area.....in fact it's inconsistent that you decided to fully boost that area in your 2nd EQ (albeit I understand your target curve there is 1.5dB less than Harman at that point, but still you boosted that area more for your 2nd EQ. Your approach is not consistent here, are you trying to make it that your non-Harman EQ sounds better than your Harman EQ in your first EQ - at least be consistent.
To conclude I'll reiterate that I think you need to be super ultra clear that your second EQ is not using the Harman Target because it's very misleading currently, and I think you should also scrap EQ's that aren't to the Harman Target, as it's "unfounded". Sorry, poor approach to your EQ's there, really poor, a number of things irking me with that approach, hence I didn't pull any punches in this post.
EDIT: you're also aligning the target curve too high on the measurement, which would leave above 10kHz being well below what would sound good to most people, most people would have to use a High Shelf at 11kHz to boost the area above that to make the most of your EQ's as they currently stand for this headphone. Sometimes your EQ's look quite optimal, but you really screwed the pooch with the EQ on this headphone, as well as misleading by introducing a new target that isn't Harman for your second EQ.
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Wow.
It's the misleading non-Harman Target for the 2nd EQ that is not made clear that it's not Harman, combined with the massively inconsistent approach between deciding to boost the 3-6kHz fully for one EQ but not for the other, that is just really strange & super poor, so I had to spell it out to people, because most people would not notice these differences when reading the post or using the EQ's. It needs to be clear, hence pulling no punches here. His EQ's are sometimes pretty optimal in my eyes, but this one is inconsistent/misleading/and poor as a whole, got to be made clear. It will certainly sound better than no EQ, but that's not the point I'm making.
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I'm really not sure why you need to be throwing any punches, much less not pulling them. Who exactly are you trying to protect from this non existent threat of a non Harman compliant curve? The adults on this forum?
Step out of the bubble Rob, because that first post was just obnoxious and rude.
I'm guessing the description that @Maiky76 provided with the two curves was misleading and not clear enough for you? Seems pretty clear to me.
First one:
Second one:
I have to say, I really like @Maiky76 's approach to generating EQs using a genetic algorithm while specifying fixed complexity as one of the targets. What's more, in a few examples where I had a chance to compare his EQ settings to others, I preferred @Maiky76's. Of course this being a purely personal, subjective preference.
I just wanted to make clear the illogical & misleading nature of his two EQ's he posted, for the reasons I mentioned. Anyone that can "read" EQ's and has enough experience/knowledge of interpreting them would realise that there's some absurdities at play there when you compare his two EQ's, and also the misleading nature of not making it clear that the 2nd EQ was to a different target curve (not Harman). I used a bit of drama to emphasise the point as I think it's bad to mislead, especially on this forum where we like transparency in all it's forms - as well as communication. I realise that not many people would notice the points I brought attention to within Maiky's EQ, both people that casually read his post & also those that actually use/try his two EQ's - so I wanted to make my points very clear to the readers.
I'll outline it here just once more to be clear:
1. He boosts 3-6kHz significantly less in the Harman EQ than he does in the non-Harman EQ, and that's when the non-Harman EQ has a lower target in that same 3-6kHz area- so that's an absurdity right there, and would also be misleading for people listening to both EQ's and comparing them. Additionally, as this headphone has wide dips rather than sharp dips, then these areas can be fully EQ'd to target with no ill effect, so both of the two EQ's should have been boosted to the target in this area.
2. He didn't make it totally clear that his second EQ was using a non-Harman Target. This is misleading to most readers as it looks very similar. It's also questionable why a 'random' target has been used in the first place that doesn't have any research behind it, and I don't think it should be published unless made absolutely clear that it is not the Harman Target.
3. Bad choice of aligning the target too high on the measurement, therefore frequency response above 10kHz would be too low for most people. This is a smaller point in comparison to points number 1 & 2 above.
I think for someone like @Maiky76 who is regularly creating EQ's as service for each of the headphone reviews, I think it should be held to similar standards of clarity / consistency / & logic that we strive for here on ASR. I will say that I realise he's doing it for free and the goodness of his heart, so I have been hard on him, and I've been dramatic in my posts, but I wanted to make the points clear & to emphasise the importance.
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Maiky76
Senior Member
It is not the first time you point out that I don’t make it clear that the target is changed and this time I am not the one that point out that it is clearly stated… BTW it is also clearly indicated in the name of the EQ config file that people who actually try these EQ will download. If that's not enough i don't know what is.
So, you say:
“misleading, inconsistent, “unfounded"
"inconsistent/misleading/and poor as a whole,"
"I just wanted to make clear the illogical & misleading nature of his two EQ's he posted”
Here is the rational behind the “taste” curve that I sometimes use when the HP has a lot of boost to be added (12dB+ and the corollary loss of dynamic range) in this case I feel that it is a lot already, plus Amirm who listens to the headphone did not fully compensate the HF so I did take that on board when I designed the EQ.
Anyhow let me try to be clearer:
“Factors that Influence Listeners’ Preferred Bass and Treble Balance in Headphones“ https://www.aes.org/e-lib/browse.cfm?elib=17940
Note that the HF modification starts @800Hz with significant change @3000 - 6000Hz and up.
I think you are familiar with high-shelf biquads from what we have done on the JBL 308…
" Segmentation of Listeners Based on Their Preferred Headphone Sound Quality Profiles” https://www.aes.org/e-lib/browse.cfm?elib=20289
This study, demonstrated according to S. Olive that:
•A 64% (the majority) of listeners prefers headphones with a frequency response that adheres to the Harman Target Curve.
•A 15% portion of listeners prefers 3 to 6dB more bass, usually younger males and less experienced listeners.
•A 22% portion of listeners prefers 2 to 4dB less bass usually older population, and biased towards females.
Based on this data one can roughly derive preference range, neutral being the default Harman curve:
•-3dB/Neutral/+3dB/+6dB as EQ for bass preference;
•-1.5dB/Neutral/+1.5dB for as EQ for treble preference;
That means that you can still be within the “taste zone” of the Harman target while not being completely on the “majority” curve. You just change the likelihood of the EQ to be optimal for the user, but still rather close to it...
A number of people will actually prefer that, it's also a major piece of knowledge that is often ignored.
A marketing department might even tailor the default curve to cater best for a certain audience…
@amirm is probably [email protected] [email protected] as I have already casually observed, but the listening material also have an influence…
Again these EQ are starting point as clearly stated, for about a third of the population it is not the ideal curve...
What I propose is not random. You can question it in the details but it is perfectly honest, logic, consistent, clear and founded as a whole.
“Bad choice of aligning the target too high”
That has to do with the number of biquad.
If I did not restricted myself to the lower number possible, you are right I could have chosen a different normalization frequency.
I did so also to keep consistence with Amirm's EQ (similar sensitivity) but you are not wrong here. See the new EQ hereafter: initial is 6, the new one is 7 Biquads and it could probably do with one more if I really targeted the full range like I did with the [email protected]
"I will say that I realise he's doing it for free and the goodness of his heart, so I have been hard on him, and I've been dramatic in my posts, but I wanted to make the points clear & to emphasise the importance."
I did not realize that my EQs are so important and I honestly added a lot of provisions as preamble of the EQ. Like with all remedies you need to be fully aware of them before using them... I'll be adding one after that.
I’ll take that as “spare the rod and spoil the child” unless you clearly tell me otherwise.
( I hope it is the correct expression)
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You didn't answer one of my main points, which is that you have an inconsistent approach between boosting the 3-6kHz in both EQ's. You can see from your graphs that you boost the Harman EQ in that area by only about +7dB, see following pic #1, yet on the Reduced High Frequency "Harman Curve" EQ you boost that same area by a massive +11dB (see pic #2 further below) - which is ridiculously inconsistent and counter to the actual targets you're using, because you're boosting the 2nd EQ significantly more even though it has a lower target in that 3-6kHz - that is super illogical and really questions your understanding / logic & competence in this domain. See the red circled parts in the pics below.
Pic #1:
Pic #2:
My point also stand about my other main point I brought up, I really don't think you're labelling the difference clearly enough between your two curves to make it clear, if you can't see that or can't figure out a way to make it clearer then I don't quite understand how you don't have those communication skills.
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