This is a review and measurements of the Sony MDR-7506. I purchased this headphone last year due to reputation of getting some of the highest scores relative to Harman preference curve. It costs US $89 on Amazon including Prime shipping.
I like the look and feel of the MDR-7506:
The headphone itself is very light and compact. Alas the coiled cord is rather heavy and has a habit of falling to the floor because of it.
While this headphone is new to me, its original -- the MDR-V6 is not. When I was visiting the major music labels back in early 2000s, the MDR-V6 was one of the top three or so respected headphones (Sennheiser and Stax being the other two). So I purchased a V6 but hardly used it and unfortunately have little memory of it. I thin I gave it to one of my sons years ago.
I was surprised how uncomfortable the MDR-7506 is. It would pinch the outer areas of my ears to a point where I could not wear then for more than a few minutes. I realized then that taking my glasses off helped but I still could not tolerate them for than 15 to 20 minutes. There is a lot of headband pressure and due to the small cups, it lands on the other part of ear. Strangely, I don't remember this about the MDR-V6? Is it possible my ears have grown in ensuing years and no longer fit inside these cups? The thought is too scary to consider!
Sony MDR-7506 Measurements
Let's get right into it with the MDR-7506 frequency response and comparison to our target preference:
As you can see, there is good bit of variation between the two cups. Being a small headphone, I had a lot more trouble getting consistent fit between the two channels. Still, I think the results are pretty correct as they correlate quite well with other measurements. The one area of deviation is that peak around 11 kHz. Other measurements including that of Harman's show that shooting way up. The older couplers tended to exaggerate the response in that region which my new GRAS 45C coupler avoid. Still, hard to know what the truth is there.
Back to the measurements and just looking at the green calibrated channel, we see excellent agreement with our target curve (dashed blue) from about 100 Hz to 2 kHz. Past that we overshoot the curve and stay above up to 8 kHz or so. This naturally will make the headphone sound bright and potentially with wider soundstage.
Bass department has the usual droop but much less than some others.
Overall one can see how this headphone that can higher agreement with Harman preference curve than many other. You can see this clearly in the deviation from our target:
Notice the broad area at or around 0 dB deviation.
So far there was good news. What wasn't good news is what followed, namely distortion measurements:
Oh wow! This headphone has more distortion at 94 dB than many do at 114 dB in bass! We are also usually spoiled by headphones having very little distortion above 1 kHz or so. Not here. We have distortion where our hearing is sensitive as well. Distortion in bass was so high that it overshot the graph so I changes scales:
Nearly 20% distortion at around 55 Hz at 114 dB. Here is another view of the 94 dBSPL and its breakdown:
This will be a good test of how important distortion is relative to frequency response -- a battle we constantly have here and in context of speakers.
Group delay is rather calm as this graph goes:
We don't see the large spikes in high frequencies. Maybe smaller cups create less of these against the body of the measurement fixture?
Impedance is variable so take care in using any amplifier that has high impedance:
Sensitivity is very good so you don't need much power to drive them.
Sony MDR-7506 Listening Tests
I remember being quite disappointed when I listened to the MDR-7506 last year when I purchased it. I neither liked the sound, nor the comfort. It quickly sat on my desk collecting dust. With much more careful testing now I can tell why. You all know that I am a fan of sub-bass performance and evaluating such at higher levels. Not so here. I initially boosted the sub-bass and it became ugly. It became boomy (harmonics travel to upper bass and cause that) with the notes not being clean and sharp at all.
Then there were the highs. Oh man these are ugly highs. Sharp and uncomfortable. Yes, the mid-range tonality was good but I just could not focus on it. Every bass note sounded ugly, and every high note was a punch in the face. Overall there was this poor quality and grittiness I could not get past.
Took out the EQ tool and made some improvements:
As I said, I boosted the lows but immediately took that out and focused on the peaking between 2 and 8 kHz. That resulted in the two filters that you see. That provided good relief from the sharp highs but I still did not like the sound. Per above, it just didn't sound clean to me. Remembering a trick from my speaker optimizations, I actually filtered out some of the sub-bass and that made a nice improvement in clarity and fidelity. Ironically, even though I was cutting out the lows, the overall tonality is much warmer with better bass than no EQ at all because the highs were taken down.
Usually once I EQ a speaker or headphone, I get much better sound and am happy with it. Not here. Taking down the highs collapsed the little soundstage that was there, leaving me with a dull, middle of the head image. I am extremely sensitive to the harshness of the highs so this was the proper compromise for me but even I could not tolerate the boring spatial effect.
The loss of deep bass was a miss too. I could no longer enjoy any of my tracks with such content.
Mind you, on some tracks I thought the fidelity was better than many speakers but in the context of all music played and comparing to other headphones, the results was simply not competitive.
Conclusions
Boy, talking about getting myself in a pickle giving such low scores subjectively to a headphone that has done so well in research. There are two possibilities:
1. Something is wrong with me and my hearing and I would not feel this way in controlled testing.
2. I am far more bothered by the listeners in research by a) too much energy in treble region and b) distortion. A related factor to this is content used for testing. Without the right content a lot of the issues I found would not be audible or as bothersome.
Then there is the issue of comfort. I see there are a lot of aftermarket pads for these so maybe that can be solved. But then the cost goes up.
Overall I can't see a good reason to recommend the Sony MDR-7506. It gets some important things right (mid-range tonality) but so many things wrong that I just can't tell anyone to go and get one. If you have it, please give the above EQ a test and report what you think.
So there, we have another massively popular headphone covered so that we have a reference for other headphone reviews to come.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
I like the look and feel of the MDR-7506:
The headphone itself is very light and compact. Alas the coiled cord is rather heavy and has a habit of falling to the floor because of it.
While this headphone is new to me, its original -- the MDR-V6 is not. When I was visiting the major music labels back in early 2000s, the MDR-V6 was one of the top three or so respected headphones (Sennheiser and Stax being the other two). So I purchased a V6 but hardly used it and unfortunately have little memory of it. I thin I gave it to one of my sons years ago.
I was surprised how uncomfortable the MDR-7506 is. It would pinch the outer areas of my ears to a point where I could not wear then for more than a few minutes. I realized then that taking my glasses off helped but I still could not tolerate them for than 15 to 20 minutes. There is a lot of headband pressure and due to the small cups, it lands on the other part of ear. Strangely, I don't remember this about the MDR-V6? Is it possible my ears have grown in ensuing years and no longer fit inside these cups? The thought is too scary to consider!
Sony MDR-7506 Measurements
Let's get right into it with the MDR-7506 frequency response and comparison to our target preference:
As you can see, there is good bit of variation between the two cups. Being a small headphone, I had a lot more trouble getting consistent fit between the two channels. Still, I think the results are pretty correct as they correlate quite well with other measurements. The one area of deviation is that peak around 11 kHz. Other measurements including that of Harman's show that shooting way up. The older couplers tended to exaggerate the response in that region which my new GRAS 45C coupler avoid. Still, hard to know what the truth is there.
Back to the measurements and just looking at the green calibrated channel, we see excellent agreement with our target curve (dashed blue) from about 100 Hz to 2 kHz. Past that we overshoot the curve and stay above up to 8 kHz or so. This naturally will make the headphone sound bright and potentially with wider soundstage.
Bass department has the usual droop but much less than some others.
Overall one can see how this headphone that can higher agreement with Harman preference curve than many other. You can see this clearly in the deviation from our target:
Notice the broad area at or around 0 dB deviation.
So far there was good news. What wasn't good news is what followed, namely distortion measurements:
Oh wow! This headphone has more distortion at 94 dB than many do at 114 dB in bass! We are also usually spoiled by headphones having very little distortion above 1 kHz or so. Not here. We have distortion where our hearing is sensitive as well. Distortion in bass was so high that it overshot the graph so I changes scales:
Nearly 20% distortion at around 55 Hz at 114 dB. Here is another view of the 94 dBSPL and its breakdown:
This will be a good test of how important distortion is relative to frequency response -- a battle we constantly have here and in context of speakers.
Group delay is rather calm as this graph goes:
We don't see the large spikes in high frequencies. Maybe smaller cups create less of these against the body of the measurement fixture?
Impedance is variable so take care in using any amplifier that has high impedance:
Sensitivity is very good so you don't need much power to drive them.
Sony MDR-7506 Listening Tests
I remember being quite disappointed when I listened to the MDR-7506 last year when I purchased it. I neither liked the sound, nor the comfort. It quickly sat on my desk collecting dust. With much more careful testing now I can tell why. You all know that I am a fan of sub-bass performance and evaluating such at higher levels. Not so here. I initially boosted the sub-bass and it became ugly. It became boomy (harmonics travel to upper bass and cause that) with the notes not being clean and sharp at all.
Then there were the highs. Oh man these are ugly highs. Sharp and uncomfortable. Yes, the mid-range tonality was good but I just could not focus on it. Every bass note sounded ugly, and every high note was a punch in the face. Overall there was this poor quality and grittiness I could not get past.
Took out the EQ tool and made some improvements:
As I said, I boosted the lows but immediately took that out and focused on the peaking between 2 and 8 kHz. That resulted in the two filters that you see. That provided good relief from the sharp highs but I still did not like the sound. Per above, it just didn't sound clean to me. Remembering a trick from my speaker optimizations, I actually filtered out some of the sub-bass and that made a nice improvement in clarity and fidelity. Ironically, even though I was cutting out the lows, the overall tonality is much warmer with better bass than no EQ at all because the highs were taken down.
Usually once I EQ a speaker or headphone, I get much better sound and am happy with it. Not here. Taking down the highs collapsed the little soundstage that was there, leaving me with a dull, middle of the head image. I am extremely sensitive to the harshness of the highs so this was the proper compromise for me but even I could not tolerate the boring spatial effect.
The loss of deep bass was a miss too. I could no longer enjoy any of my tracks with such content.
Mind you, on some tracks I thought the fidelity was better than many speakers but in the context of all music played and comparing to other headphones, the results was simply not competitive.
Conclusions
Boy, talking about getting myself in a pickle giving such low scores subjectively to a headphone that has done so well in research. There are two possibilities:
1. Something is wrong with me and my hearing and I would not feel this way in controlled testing.
2. I am far more bothered by the listeners in research by a) too much energy in treble region and b) distortion. A related factor to this is content used for testing. Without the right content a lot of the issues I found would not be audible or as bothersome.
Then there is the issue of comfort. I see there are a lot of aftermarket pads for these so maybe that can be solved. But then the cost goes up.
Overall I can't see a good reason to recommend the Sony MDR-7506. It gets some important things right (mid-range tonality) but so many things wrong that I just can't tell anyone to go and get one. If you have it, please give the above EQ a test and report what you think.
So there, we have another massively popular headphone covered so that we have a reference for other headphone reviews to come.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
