Sennheiser HD650 Review (Headphone)

[pkane]

Well, we got the Headphone Harman Curve to rely on as a Target Curve....which is kinda all we got when it comes to measurments & targets. That doesn't show a peak at 7kHz, therefore if you're EQ'ing to the target curve then you'd remove that peak if it was consistent across all your measurements. I can't really speculate on the finer points you make. More specifically re your measurements, I'm not sure you can really use them to EQ your headphone, because it's not like you'd overlay the Headphone Harman Curve on your measurements and then EQ to that, because the Headphone Harman Target Curve is only specific to that particular GRAS unit and not your own head & HRTF....so that's not valid. If you've got in ear microphones (which you do), then you could have a stab at creating your own Target Curve......I've loosely thought about doing that in my own room with my flat anechoic EQ'd speakers which are at equidistant triangle from my listening position....do a REW sweep & measure from those in ear microphones, that would be a simulation target of your speakers in your room.....don't know too much about the specifics of making this happen as not researched it due to not really needing to as Harman Headphone Target sounds accurate to me. Could be an interesting project, sure people have done it before. You'd then measure your headphones on your head like you have done, and then EQ to your determined Target Curve. I'm certain there's lots of practical pitfall details associated with trying to do this!

Well, the latest version of Earful actually has a feature designed to help equalize headphones to speakers. It alternates the test tones (or noise bursts) between speakers and headphones, with speaker level kept constant while headphones being adjustable along a frequency spectrum. You decide how much of the frequency range you want to cover, and with how many data points. YMMV

 

[amirm]

If we spend too much time trying to "correct" these variations to some specific, static target, we may just be destroying or distorting information that the ear expects to receive to perceive the sound as being more natural.

For this reason, I only correct a response there if the peak exceeds preference and listening tests confirm the same. Otherwise, that region is best ignored as far as specific correction. I also sometimes use plain shelf EQ in the high region just to correct tonality.

 

[Robbo99999]

Well, the latest version of Earful actually has a feature designed to help equalize headphones to speakers. It alternates the test tones (or noise bursts) between speakers and headphones, with speaker level kept constant while headphones being adjustable along a frequency spectrum. You decide how much of the frequency range you want to cover, and with how many data points. YMMV

My intuition is that the measurement approach is better than the subjective matching approach.

 

[pkane]

My intuition is that the measurement approach is better than the subjective matching approach.

Isn't Harman's curve derived from an average subjective impression by a group of people that are in no way related to you, other than being human (possibly)? I'm of the opinion that given an average subjective preference of a group vs. my own, I'll take my own. But again, YMMV.

 

[amirm]

Isn't Harman's curve derived from an average subjective impression by a group of people that are in no way related to you, other than being human (possibly)?

All of our knowledge of psychoacoustics is created that way. Are you suggesting the whole science is useless? If so, how come MP3 works by throwing out 90% of the music and still sounding like the original to vast majority of people?

 

[amirm]

I'm of the opinion that given an average subjective preference of a group vs. my own, I'll take my own.

The problem is that you can't evaluate your own hearing/preference as well as the controlled studies can. And those studies say that we are far more alike, than different.

 

[pkane]

All of our knowledge of psychoacoustics is created that way. Are you suggesting the whole science is useless? If so, how come MP3 works by throwing out 90% of the music and still sounding like the original to vast majority of people?

This is where we disagree. Controlled studies, like Harman's, are great for coming up with common patterns across a large group. Not so much for coming up with what sounds best to me, personally. These may or may not be the same, and the only way I'll know is by trying, not by accepting that the group average is the best possible sound I can achieve because that's what Harman's study group preferred, on average.

MP3 is a poor comparison, since that's used at the source, with no way to individualize the results for each listener. By necessity, it was developed to appeal to the largest possible group. Headphone EQ is different, as I can easily create my own, personalized version.

The problem is that you can't evaluate your own hearing/preference as well as the controlled studies can. And those studies say that we are far more alike, than different.

I don't buy this. What prevents me from evaluating my own hearing/preferences, other than the lack of appropriate test methodologies and software/hardware? If your goal is to deliver a target that works best for a large group of people, Harman is as good a source as any. If your goal is to find out what works best for you personally, I'd expect that there should be a way to this and will continue to look for how.

 

[Robbo99999]

This is where we disagree. Controlled studies, like Harman's, are great for coming up with common patterns across a large group. Not so much for coming up with what sounds best to me, personally. These may or may not be the same, and the only way I'll know is by trying, not by accepting that the group average is the best possible sound I can achieve because that's what Harman's study group preferred, on average.

MP3 is a poor comparison, since that's used at the source, with no way to individualize the results for each listener. By necessity, it was developed to appeal to the largest possible group. Headphone EQ is different, as I can easily create my own, personalized version.



I don't buy this. What prevents me from evaluating my own hearing/preferences, other than the lack of appropriate test methodologies and software/hardware? If your goal is to deliver a target that works best for a large group of people, Harman is as good a source as any. If your goal is to find out what works best for you personally, I'd expect that there should be a way to this and will continue to look for how.

We shouldn't go too far down the "rabbit hole" in review threads when the age old arguments surface again.....I'm sure there's specific threads for that somewhere. Sometimes you can't help a bit of discussion at a tangent to a review thread where there is useful stuff to be gained by it no doubt, but these are age old arguments now.

 

[pkane]

We shouldn't go too far down the "rabbit hole" in review threads when the age old arguments surface again.....I'm sure there's specific threads for that somewhere. Sometimes you can't help a bit of discussion at a tangent to a review thread where there is useful stuff to be gained by it no doubt, but these are age old arguments now.

Can't help myself

 

[Robbo99999]

Can't help myself

Ha, I know, I agree, it's easy to get diverted (me too).....conversations have a flow and then develop into other topics, but we had a recent aim to try to keep review threads relatively clean of the age old topics that keep arising that aren't directly relevant to the product under test:
https://www.audiosciencereview.com/forum/index.php?threads/new-rules-for-review-threads.18744/
I think some brief diversions are ok & even informative & especially if somehow related, but when we get into age old repeated arguments territory......

 

[Morpheus]

Why ?
1: There is production spread between HD650's
2: Amir's HD650 is many years old (mine is even older).
3: Sonarworks has measured many (possibly hundreds) of them and found differences between HD650's over the years (see SBAF post).
4: There are others that measured a few HD650's and there is definitely a production spread among them.
5: I have been told by someone that contacted Sonarworks and he claims he was told HD6XX do not measure exactly the same as HD650 from the same time period.
6: What makes it so that only Amirs setup is conclusive where there are more people around measuring with similar or the same setups ?




That's because a bass has higher overtones than the fundamental in most cases.
The HD650 is 50Hz 0dB (on my rig and to my ears) but is masked' a bit by the elevated upper bass/lower mids.
Amirs measurements appear to show more bass roll-off due to the Harman curve.
When EQ'ed to Harman bass you get more 'body' and 'impact' but not everyone prefers this.
It does sound warm, full and 'bassy' to me but not extended. With the EQ set as I do it (20Hz +5dB, 30Hz +3dB, 40Hz +1dB and the midbass hump removed it sounds extremely realistic to me. A pinch too warm in stock.

 

[Haze]

I have to hand it to you Amir I've had my HD650s for almost 15 years and that's one of the best EQ's I've heard for them.

 

[Sal1950]

I have to hand it to you Amir I've had my HD650s for almost 15 years and that's one of the best EQ's I've heard for them.

Is there a "headphone EQ for dummies" thread or some-such thing out there that gives basic instructions on how to plug in this curve?
TIA

 

[brachypelma44]

Is there a "headphone EQ for dummies" thread or some-such thing out there that gives basic instructions on how to plug in this curve?
TIA

This, pretty much.

https://www.audiosciencereview.com/...ds/list-of-amirs-headphone-peq-filters.18590/

I use PEACE to do it on the PC in the office, and hardware EQ in the home theater room where there is no PC.

 

[Tachyon88]

Wellz....the reason my EQ didn't sound good is because I was using the ot1990 settings for the LCD2C - DOH !

Between my EQ, Amir and ot1990 all sound very similar. I will have to listen much more to determine which I like best.

 

[Sal1950]

This, pretty much.

https://www.audiosciencereview.com/...ds/list-of-amirs-headphone-peq-filters.18590/

I use PEACE to do it on the PC in the office, and hardware EQ in the home theater room where there is no PC.

OK Thanks, I'll look into seeing if any of it is applicable to Linux installs.

 

[Sal1950]

It is is more wholesome now.

Oh My, not a EQ for me then. LOL

 

[bobbooo]

To be honest, I have no clue what to make of that one graph. I can't even see how many measurements have been made, and there is no information as to what the measurements are. What conditions changed and which line corresponds to what.
However, in general I would be looking to try to identify individual physical mechanisms that were apparent in moving the response from the optimal. And do this for each measurement individually. Look to see which were common between measurements and decide on possible compensation parameters. If averaging is needed I would be looking to average the parameter settings for each given compensation, not averaging the measurements before calculating compensation. I might want to pick the modal value (for instance) for compensation, not the average. Those variations between measurements carry important information. Just averaging them away is not a great idea.

We don't fiddle about for hours, minutes or even seconds finding the 'optimal' positioning when wearing headphones - most will just put them on their heads and press the play button. Measuring multiple positions is a simulation of the real-world variation of this process, and averaging them will statistically get you closer to the response you'll hear any particular time you put on the headphones.

 

[amirm]

Measuring multiple positions is a simulation of the real-world variation of this process, and averaging them will statistically get you closer to the response you'll hear any particular time you put on the headphones.

Once again, it will NOT. Average all the temps for each day of the year. How is that more accurate prediction of the temp tomorrow? It will not be. Indeed it will be garbage data in that regard.

Averaging is a concept to make humans understand large set of numbers. It filters from many data points to just one. Intuitively then you should accept that it is sharply reducing fidelity, not increase it. You sound like there is some magic dust in averaging.

If the system has variance, then you want to keep that in mind in how you interpret the data, not throw out the variation and pretend there is one answer (the average).

As I have explained, averaging is just a low pass filter. It gets rid of variations in data whether real or not. Stop using lay intuition of it having some magic in it where it pops out the real usage of something. Averaging brings no power to predict how you wear the headphone.

So no, in no way it "gets you closer to the response of when you wear the headphone." It has zero impact on that.

If variance is too high then the methodology itself needs to be questioned and dealt with. Not accepting that and then trying to cover it up with averaging. You must do everything in your power to get good data to being with, or know that you don't have good data and make decisions accordingly.

 

[Rock Rabbit]

Once again, it will NOT. Average all the temps for each day of the year. How is that more accurate prediction of the temp tomorrow? It will not be. Indeed it will be garbage data in that regard.

Averaging is a concept to make humans understand large set of numbers. It filters from many data points to just one. Intuitively then you should accept that it is sharply reducing fidelity, not increase it. You sound like there is some magic dust in averaging.

If the system has variance, then you want to keep that in mind in how you interpret the data, not throw out the variation and pretend there is one answer (the average).

As I have explained, averaging is just a low pass filter. It gets rid of variations in data whether real or not. Stop using lay intuition of it having some magic in it where it pops out the real usage of something. Averaging brings no power to predict how you wear the headphone.

So no, in no way it "gets you closer to the response of when you wear the headphone." It has zero impact on that.

If variance is too high then the methodology itself needs to be questioned and dealt with. Not accepting that and then trying to cover it up with averaging. You must do everything in your power to get good data to being with, or know that you don't have good data and make decisions accordingly.

Not to make a fight about statistics...but the "magic dust" is called the "big numbers law" or many measurements (lab) tend to the expected value (nothing new), very time consuming. If the variance is high ....it means by definition that you have a good expected value first! ( meaning a large set of values). I know that acoustic measurements are anything but stable and one don't waste time in repetitions (variables even depends on temperature and humidity).
Average may not have a power for predictions but is a useful tool for better precision (at least at math level and lab), on the other hand it can not predict our "average" hearing ability on hp (many variables)
BTW we know of global warmth by the average global temperature in many decades...and the predictions seems good (in a bad way).
BTW2: the volt reference is an average of Josephson devices...not a "single" measure.