Studio headphone review: Sony MDR-7506
There are very few headphones which have survived three decades and still remain as the main workhorse for many sound professionals around the world. The Sony MDR-7506 started out as the MDR-V6 exactly 30 years ago. Understandably back then the headphone landscape was much different and these were an instant favourite amongst many sound engineers. Praised for not only great sonic performance but also well thought out ergonomics the MDR-V6 became a classic and Sony decided to do a slightly higher priced spin-off and call it the MDR-7506. The younger brother of the V6 has slightly better build quality and initially used the same driver with samarium-cobalt magnet which was in the late 90-ies replaced with a stronger neodymium magnet. Unfortunately the magnet swap happened without changing the serial number, hence it’s hard to know what version exactly one has.
Traditionally the MDR-7506 has been a favourite amongst live sound engineers and looks like this means that these Sony headphones have found their way into studio control rooms as well. Like the equally venerable Yamaha NS10 monitor it has become something like a standard amongst many practicioners, but does its live sound pedigree automatically make it good for mixing and mastering – read on to find out!
Uncalibrated sonic performance
The MDR-7506 is known for its bright-ish sound signature, which is usually thought to be “the” studio sound. Our measurements show that the MDR-7506 could actually be well suitable for live sound aplications, but for studio use most will find it to be rather bothersome.
First off – it’s safe to say that this Sony headphone isn’t known for its bass. The low end starts to roll off at 50Hz which doesn’t mean that you’ll be missing much of the music, however for serious studio use it is insufficient. High THD doesn’t help here – for most of the samples we measured it peaks at significant 15% at 100Hz. Your 808 kick tail will have possibly nice drive to it, but do not be fooled by it – its the headphones that are giving those nice overtones not the sample! We would recommend avoiding mixing bass with these headphones at all costs.
100Hz – 2KHz shows good linearity with minimum channel differences. This is the region where usually most of the musical information resides, so despite its other shortcomings the MDR-7506 does much right. Usually if your mids aren’t on point, then who cares about the rest? Pretty sure that it’s the clean mids which are responsible for MDR-7506’s fame.
After 2Khz is where the real trouble starts. Severe peaking starts in this region right up to 10KHz where a gradual peak up to +10dB makes these sound very harsh and at times sibilant. We can see this might be useful in live applications, like when you need to quickly check for some hissing or noise in some channels. Also you will get extra lows and mids from the PA (and room) whilst wearing these, so for live applications this peaking could actually make sense, but not for making critical mixing decisions. In studio environment the high frequencies will be very disorienting. Most music simply sounds harsh on these cans. The hihats and cymbals will just be too much to bear. Also the de-essing can not be properly done, just like on the M50x. Your mixes most probably will sound quite dull on other systems. All in all these would be rather good headphones if it wasn’t for the over hyped highs.
Interestingly enough the very top octave on the MDR7506 is pretty tame. After 11KHz there is a steep roll-off, which masks many overtones for both instruments and vocals. The perceived effect is a congested sound with very little stereo width.
Calibrated sonic performance
The calibration effect on the MDR-7506 is very pronounced. Contrary to the “fun” sounding Audio Technica M50x, post-calibration the MDR-7506 becomes not only more precise, but also euphonic – you can actually start to enjoy listening to some tracks on it!
Extra low bass extension will surely be gained by calibration, however the performance ceiling is largely set by poor THD performance in mid-bass frequencies. Tonal richness caused by THD still persists, therefore bass mixing is rather problematic.
The linearity increase in mids won’t be easy to detect, however stereo image will be more precise if individual calibration is used. This is where Sony really did it right and Sonarworks plug-in keeps those clean mids intact.
Highs is where the most work will be done. Sonarworks plugin removes the “AM radio” tinny sound by completely removing the enormous peak at 2KHz-10KHz, hihat and cymbal tone is completely transformed. Well recorded female vocals and many string overtones will sound much more natural, hence they can finally be mixed with confidence.
The 11KHz-20KHz dip is restored to neutral as well. Overtones and spatial cues can be easily heard, making the sound wider. Instruments are more easy to detect in phantom stereo image. This top octave might not be much in the big picture, but we make sure you can hear all of it.
As a live sound tool the MDR-7506 should be able to withstand daily abuse from being dragged to and fro various gigs. Earcups are made from metal as well as the headband which is wrapped in pleather.
MDR-7506 users should always make sure that their headphones have earpads in good condition, otherwise the headphone starts to lose much of its bass. Luckily the pads are swappable and there are many types to choose from. One must however keep in mind that earpads change the sound signature, hence calibration will only work as intended with pads of the same type.
Over the years Sony has decided to stick with a non removable cable, which for a headphone if this type can cause problems. A swappable cable means that you can get back into action if you’ve broken a cable mid-gig.
After analyzing these headphones it’s no surprise why the MDR-7506 is so loved by many sound engineers. These headphones are clearly made for live sound and on-site recording work as is evident by how rugged are they made. At the same time we were pretty underwhelmed how the MDR7506 performed in studio where a neutral sound signature is needed. Uncalibrated these should not be used as a primary studio monitoring tool.
Things do change for the better when Sonarworks calibration is used. The MDR-7506 completely changes its character and becomes a useful tool for mixing many types of music. Bass performance still suffers, could be due to the respectable age of this headphone design, but all in all – the performance gain is tremendous. Calibration is a must for every MDR7506 user, if critical mixing work is planned with these headphones. Sony has done well with this headphones ever important midrange, but we all know that devil is in the details.
Sonarworks is an acoustic calibration software development startup. For years, the company has been working with custom studio and headphone calibrations for awarded sound engineers. The technology behind measurement and calibration is a result of more than 3 years work and 1M USD investment in R&D. The headphone reviews are based on numerous measurements in our lab and feedback from our professional clients. More about our headphone calibration: http://sonarworks.com/headphones/overview/