[StudioSound]

Just got a pair of these to measure yesterday.

 
I look forward to seeing your results.

I was wondering: have you considered taking/distributing impulse measurements from the headphones that you measure, so that you can run them through a convolution engine and correct their response?

This is relatively easy to do yourself for speaker room correction, but measuring headphones accurately is a lot more difficult. It seems like that would be interesting to experiment with.

 

[jackson1]

I was wondering: have you considered taking/distributing impulse measurements from the headphones that you measure, so that you can run them through a convolution engine and correct their response?

 
That would be brilliant. Imagine having support for the Sony 7520 in something like the Sonarworks headphone calibration software by providing them with measurements of the 7520... I was asked by Sonarworks to send in my 7520 for measurement so they could get a profile and support the headphones, but I declined due to being too scared to ship them. I'm in Europe and I would be in serious trouble re-acquiring them if they got lost or damaged.

 

[Mike F]

Here we go folks:-
 
http://www.innerfidelity.com/content/innerfidelity-april-2015-update
 
http://www.innerfidelity.com/images/SonyMDR7520.pdf

 

[Mike F]

Not sure what to make of this, and measurements in general. I have to say that it looks like a fairly typical Sony headphone frequency response graph to me though. Strange that Sony studio headphones tend to measure 'badly', (think 7509HD) but sound very good - to many people at least. Strange also that by all accounts mixes done on the 7520 translate exceptionally well. There are several threads on the pro gear forum, Gearslutz, where the 7520 is highly regarded as a mixing tool.
 
On the other hand, and rather ironically, the Sony studio headphone that actually measures well - the 7506 (V6), is generally regarded as sounding inferior to the above two phones, and only a handful of people would dream of using them for mixing!

 

[jackson1]

Tyll's listening impression of our beloved 7520 is quite a contrast to what's been reported in this thread:
 
Sony MDR-7520 - Oh bummer. This was a much anticipated measurement for me as it's got a bit of a following out there and people keep asking for a measurement. It had no sense of sub bass, and the upper bass was somewhat bloated. The mid-range was good, but the treble fell apart. It wasn't honky, but it was a mid-fi sounding headphone to me. Sent in by RandyB. Sorry 'bout the hard words, mate.

 

[Mike F]

  Tyll's listening impression of our beloved 7520 is quite a contrast to what's been reported in this thread:
 
Sony MDR-7520 - Oh bummer. This was a much anticipated measurement for me as it's got a bit of a following out there and people keep asking for a measurement. It had no sense of sub bass, and the upper bass was somewhat bloated. The mid-range was good, but the treble fell apart. It wasn't honky, but it was a mid-fi sounding headphone to me. Sent in by RandyB. Sorry 'bout the hard words, mate.

 
I can agree with the highlighted part, but find the rest of his impressions somewhat mystifying. 'No sense of sub bass...... mid-fi sounding.......'?
 
Still, it's good that Tyll has an opinion and says what he thinks.

 

[mireque]

Really don't know what to think about Tyll's measurements on 7520. Extremely surprised.
 
It doesn't correlate to what I've been hearing since I've acquired them cca 2,5 years ago, and I also own professionally treated studio with Neumann monitors and subs, so I can quite compare what's neutral and accurate (my room is linear and goes accurately down to 22Hz). I can tell you Sonys are on par with Neumanns, at times I prefer working with 7520s solely, they're that good to me and I hear they go pretty deep without any distortion. I only fear when the earpads are gone, because they're pretty expensive, but hopefully they will last
 
I do also have HD800 for another reference, but they aren't as clean to me as 7520. HD800 has bigger soundstage sometimes, but 7520 always wins in overall neutrality, acurateness and detail retrieval.
 
I will say it again - everything I've done in pro audio field on Sonys translated extremely extremely well to just everywhere (if they've had no subbass and/or strange highs, one would certainly notice). Even distortion graphs don't correlate to what I'm hearing. Why everybody says they sound extremely clean on low volume levels and even on high volume levels they sound clean too?
 
So, starting from today, I'm feeling even more convinced that measurements (if they're correct), only tell one part of the story. I'm much more free now from any insecurities I've had in my mind, because I was expecting 7520 to measure on paper exceptionally well.
 
Don't know if Tyll has ever been mixing/mastering for a living (even on headphones) and knows what accurate and balanced musical presentation sounds like. I don't even bother what he says from these measurements.
 
But for me, the 7520 will always be the headphones champion (certainly not mid-fi sounding)!

 

[GREQ]

I'm just going to say what some people are probably thinking... counterfeit headphone?

 

[TMRaven]

Nice to see Tyll's measurements and opinions, helps me put everyone's voices on head-fi in perspective.
 
Even Tyll will admit that measurements aren't the end-all be-all for determining everything about the sound of a headphone, but they do tell you when things have gone extremely wrong, and it looks like things have gone extremely wrong here.  

 

[StudioSound]

Well I can't say that I'm surprised to see it's another pair of Sony headphones that people like the sound of, which measure poorly.
If you consider that the MDR-7520 are a modified MDR-Z1000 design, the results do seem accurate to Tyll's setup.

http://www.innerfidelity.com/images/SonyMDR7520.pdf
http://www.innerfidelity.com/images/SonyMDRZX1000.pdf

Only the Z1000 measures flatter - which is generally the opposite of what people have reported when comparing the two, and doesn't make much sense considering the 7520 are sold as the "monitor" while the Z1000 was the "hifi" version.

I do think it would be interesting to send in a couple of pairs to see how they differ, as myself and others have reported changes over time - and I still have a pair that is completely unused as a point of comparison. Unfortunately I'm not really able to ship these in to Tyll.
But I don't know that it would be a drastic change. Probably similar to his previous results on headphone break-in.

However it does make me question headphone measurements more than ever.
If we compare the graph of the Bose QC20 to the 7520, it measures flatter and extends deeper into the sub-bass - it even has lower distortion.
But if I compare the two - and I use these as the example because I use both for several hours each day now - well, if the 7520 is "mid-fi" (which it may well be - because I don't think Tyll is using that in derogatory sense, and I do think it's been hyped up more than it should be here) then the QC20 is lo-fi and it certainly does not have deeper bass extension.
Now I love the QC20 when noise cancellation and portability is more important than fidelity, but I rarely ever find myself sitting at home using them to enjoy music.

I am not trying to say that Tyll's measurements or impressions for the 7520 are wrong - he has a lot of experience doing this - but it does make me question how useful the measurements are in general.
There are many cases of headphones which measure very similarly, but sound quite different from one another - in ways which the measurements don't seem to explain.
And as a test, I set up an EQ which was the inverse of Tyll's measurements and it sounds awful.

So I'm not really sure what to make of it.
I don't mean to suggest that the measurements are invalid - because I'm sure they're not.
And I would like to use objective comparisons wherever possible. I have been thinking about purchasing a high-end open-back headphone recently (potentially the HD800) and objective comparisons are very important to have.
But I just don't know that the measurements at InnerFidelity match my perception.

 

[TMRaven]

To be fair to Tyll's measurements, usually the better and most even sounding headphones based off his measurements have sounded very good and balanced to me-- particularly the Focal Spirit Pro, HD800, LCD series, HE-560 and Oppo PM3.

 

[c61746961]

There are many cases of headphones which measure very similarly, but sound quite different from one another - in ways which the measurements don't seem to explain.
And as a test, I set up an EQ which was the inverse of Tyll's measurements and it sounds awful.

There are many products of perception that can't appear on a signal measurement like this, soundstage and imaging for instance. The impulse response shows some HF ringing so that horrendous dip at 5-6 KHz may not be what it looks like, that's when CSD plots come in handy; I have seen many holes like these get filled with energy in less than a millisecond.

No need to lose faith in measurements, they are just a tool and serve a purpose very well.

 

[Brazenways]

I wish they measured worse.

Then I can buy more on discount.

 

[StudioSound]

To be fair to Tyll's measurements, usually the better and most even sounding headphones based off his measurements have sounded very good and balanced to me-- particularly the Focal Spirit Pro, HD800, LCD series, HE-560 and Oppo PM3.

There are many products of perception that can't appear on a signal measurement like this, soundstage and imaging for instance. The impulse response shows some HF ringing so that horrendous dip at 5-6 KHz may not be what it looks like, that's when CSD plots come in handy; I have seen many holes like these get filled with energy in less than a millisecond.

No need to lose faith in measurements, they are just a tool and serve a purpose very well.

I don't mean to suggest that Tyll's measurements are wrong, just that it seems like they may not always tell the whole story.
Perhaps the issue is that the measurements are incomplete, missing CSD plots for example.
I do agree that there is usually a good correlation between a headphone that measures well based on what is posted at InnerFidelity, and a good sounding one.

And I don't mean to suggest that the 7520 are something that they're not, but I'm very surprised to see the results as compared to the Z1000, based on the impressions from pretty much anyone that has compared the two and posted about them here, and their intended markets. (pro audio monitoring vs hifi)
From my own headphones that I currently own, the 7520 is clearly the best sounding - which I don't think is simply a preference for a non-neutral sound that boosts the bass - despite having others which are supposed to sound better based on these measurements. And I don't object to the "mid-fi" moniker if Tyll really means that they sound like what they cost, instead of sounding like something costing several times more as some have claimed. People were deluding themselves if they thought they compete with the real high-end.

None of this changes my opinion on these headphones - which is that they're still my favorite sealed headphones right now - but it does make me question how useful the measurements are when considering a new purchase. Because I don't think I would have bought the 7520 if I had access to this information at the time.

Edit: I've been looking over the InnerFidelity site comparing the graphs of some of the headphones that I have here, and have previouslycompared against the 7520, and this stood out from the ZX700 review:

  I received these headphones during one of the long burn-in tests and did quite a bit of listening before getting to see the measurements. (I usually listen first anyway, but not for this long). I was quite surprised these cans measured relatively poorly as the listening tests were quite good. Measurements aren't everything, eh?

 

[pcf]

  Tyll's listening impression of our beloved 7520 is quite a contrast to what's been reported in this thread:
 
Sony MDR-7520 - Oh bummer. This was a much anticipated measurement for me as it's got a bit of a following out there and people keep asking for a measurement. It had no sense of sub bass, and the upper bass was somewhat bloated. The mid-range was good, but the treble fell apart. It wasn't honky, but it was a mid-fi sounding headphone to me. Sent in by RandyB. Sorry 'bout the hard words, mate.

I can feel the disappointment from some of the 7520 owners here ( myself included) but I do agree Tyll's comments about the upper bass.
Don't agree the treble fell apart' or ' no sense of sub bass'. Then again I am not sure these comments form Tyll are entirely based on measurement or listening test? Maybe Tyll can clarify that?
 
I still think these are great headphones and perfect for my everyday use. I have them with me all the time now- at work; on the move... Totally happy with them.
 
Just out of interest I briefly compared the 7520 to my Grado Hp1i. The Sony's mid range feels a bit grainy and recessed by comparison. The bass seems a bit softer too.
Don't forget the Grado are many times more expensive that the 7520. No doubt which one is the better value for money though.