Sennheiser HD650 review – Long Live The King!
It’s hard to overstate the importance of the Sennheiser HD650. For Sonarworks this headphone was used to translate a neutral sound from speakers to headphones. They’re also used by our engineering team as reference headphones, so they’re really special to us. Let’s find out whether you should get excited about them!

  • Great sound out of the box without harsh high frequencies and boosted lows
  • Comfortable to wear
  • Matched left and right channels
  • Translate well among different users
  • Good price

Pros list with Sonarworks Reference calibration

  • Handles correction almost perfectly
  • Translates well among different listeners
  • Aren’t too sensitive to positioning changes on one’s ears
  • Not the most durable headphones out there
Use cases Recommended music genres:
Great for any music genre
Best use case:
Great for mixing and mastering
Not very suitable for tracking as they have open design and won’t isolate effectively
Tech specs Type
Open back, Over-ear
297 Ohm
< 0.05% (measured at 1 kHz sine wave)
Frequency response
12 Hz to 40.5 kHz
3.5 mm stereo jack
Includes 1/4″ to 1/8″ adapter
260 g (without cable)
Require headphone amp
Headphone amp

They could definitely lack volume if plugged directly in your phone or a built-in headphone socket on your laptop, especially if you’re using them with Sonarworks calibration and “Safe headroom” switch on, but don’t worry if you process sound through an audio interface – almost any interface with a headphone output will drive them loud enough.

Build quality

Usually they are made very well from pair to pair. However, if you plan to use them frequently for longer period like five years and more, be ready for some part replacement – drivers can start rumbling and distorting (especially on the low-end), headband can become loose and ear-pads will wear out over time and will definitely need a replacement. Luckily, you can order and replace literally any part on these headphones with ease.


Sennheiser HD 650 is pretty much the most neutral headphones available on the market. However, they lack sub-bass frequencies (below 100 hz) and high-mids (around 2-5 kHz) need to be tweaked a bit. Otherwise, they are good to go already out of the box.

Channel balance

You would expect from headphone manufacturers perfect matching between left and right drivers. Unfortunately, in the real world this doesn’t happen too often – pretty much every other pair of headphones have channel inconsistencies even among bigger headphone brands. By contrast, Sennheiser are true experts in offering headphones with matched left and right drivers so that soundstage stays consistent across different frequency regions. With some minor exceptions Sennheiser HD 650 has hardly any difference between the two drivers. Sometimes some pairs have slight inconsistencies in bass and sub-bass region, but this doesn’t happen so often.


Based on our experience with various headphone models, we would say that Sennheiser HD 650 are very comfortable to wear. They are lightweight, fit very well almost any head and do not cause headache by creating too much pressure for your ears and temples. These headphones would be a great choice if you plan extensive mixing sessions.


Totally. You get great sounding neutral headphones suitable for any genre production for about 300 euros per pair. What else do you need? Shut up and take (spend) my (your) money!

Observations on how headphones perform after applying Sonarworks Reference calibration Total Harmonic Distortion

These aren’t the cleanest headphones out there, when it comes to distortion in the bass region, however, they hold up nicely with anything above 150 Hz. While THD figures after calibration in the sub-bass region are high (on average about 10-15%), it’s mostly 2nd harmonic distortion, which means that it won’t be too audible and in most cases will go unnoticed even if you work with bass heavy music. Also it’s worth keeping in mind that even with their THD these headphones will reproduce cleaner bass than many of real world playback systems your work will be listened on. Should you absolutely require surgical precision under 100 Hz, get a pair of calibrated closed backs or orthodynamic headphones.

How accurate and consistent is the correction effect among different listeners?

They will sound nearly the same no matter who is using them. Also, these headphones don’t change their frequency response and overall feel when position on a head is changed.

How much do they differ pair to pair in terms of frequency response?

Based on our experience, they do not differ a lot from pair to pair. There could be a slight difference in high and high-mid frequency perception, otherwise they sound very similar.


8.4 / 9.1 / 9.6

Sound rating is a weighted average of Frequency Response, Adaptiveness, Harmonic Distortion and Channel Balance scores, with Frequency Response and Adaptiveness having the greatest influence.

7 / 9 / 10

The flatter the frequency response – the higher the score. When evaluating the frequency response score with the Average calibration profile, the pair to pair consistency of the given model is taken into account – if we have measured a considerable frequency response inconsistency among multiple pairs of the given model, the score drops, as the profile loses accuracy. Individual calibration will grant perfectly flat frequency response.


Adaptiveness shows how capable these headphones are at delivering the same perceived frequency response to any listener. Headphones with high score will sound nearly identical to everyone.


Harmonic distortion – the lower the Total Harmonic Distortion (THD) figure, the higher the score. Headphones with prominent 3rd harmonic distortion above 100 Hz will score lower.

9 / 10

Channel balance – the closer to identical the frequency response of both channels, the higher the score. Individual calibration delivers perfect channel balance.


Comfort – shows if headphones can be used for long listening sessions comfortably. Every model is tested by at least a few individuals.


Build – evaluates how well the headphones are put together, the materials used and indicates the expected longevity. Easily replaceable (and easily available) parts will boost the score. We don’t do any stress tests and very few models are used for longer than a couple of days, so this is a fairly subjective score.


Value – indicates the price-performance ratio of the given headphones and how they stack up against the competition. High score means that you won’t find more neutral sounding alternatives for the price.


Great, very close to neutral sounding, apart from the weak bass. Needs minimal tweaking for getting them perfect.

P.S. You can buy individually calibrated Sennheiser HD 650 headphones from our Store.

Final Rating

With Sonarworks Reference 4
Calibration Enabled
Without Sonarworks

Remove coloration from your
headphones with Reference 4

Learn more Supported headphones