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published: Oct-29-2017

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NO SMOOTHING is applied to the shown plots. Most measurement sites have some smoothing applied which ‘irons flat’ sharp peaks and ‘wiggles’. I do not use smoothing because some info about sound quality is lost when plots are smoothed.

Aside from a small correction of the microphone itself also some correction in the lowest frequencies is applied to the plots to compensate for the perceived loss of bass when using headphones. This is described HERE in more detail.
A ‘horizontal‘ frequency response curve on the shown frequency response plots on this website thus indicates a perceived ‘flat’ tonal signature.

ALL measurements are made with a good SEAL on a flatbed measurement rig.
The shape of your head, bone structure, pad size, pad ‘softness,  (compliance), hair or no hair and or wearing glasses may (drastically) change the frequency response of some headphones, so… your personal experience may differ substantially from these plots.

Frequency response (tonal balance) is the most sound-determining aspect of headphones. A horizontal line shows audible neutral response in the plots on this website. Deviations in different severities at different frequency bands have an effect on the sound character.
The bigger the deviation the stronger the effect.

Below an aid to help determining the sound character of headphones with relation to the frequency response.


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The HIFIMAN Susvara is an orthodynamic over-ear headphone intended to be driven directly from powerful desktop equipment only.
It retails for around € 6200.- which is quite a lot of money for a headphone.
For this you do get a smart looking (and great sounding) comfortable headphone made using fine materials and well machined parts.
The wood veneer looks very nice in combination with the metal and leather headband.
The earpads are VERY large, and also very comfortable. The out- and in-side is made of pleather (fake leather) and has cloth on the parts that touch the skin. It is an improved replacement of the HE-6.
The weight is certainly not the lightest around but is certainly less in weight than the HE-6.
Everyone around you can hear what you are playing and you can hear all ambient noises unattenuated.


Type: Over ear, open
Usage: Home with a powerful speaker or headphone amplifier
Driver type: orthodynamic
Pads: replaceable, slanted hybrid pleather/polyester cloth
Inner pad dimensions: depth: 18mm. height: 70mm, width 55mm oval shaped.
Collapsable: No, but can rotate the cups in a flat position.
Headphone connector: 2,5mm TRS (marked L and R)
Cable entry: double sided
Cable: replaceable,  3m with gold plated 6.3 mm  TRS plug
+ 3m with 4-pin XLR plug
Driver size: 80 mm
Nom. power rating: 5W (assumed)
Max. voltage: 18 Vrms
Max. current: 300 mA
Max. S.P.L.  117dB
Impedance: 60 Ω
Efficiency: 80 dB/1mW  (92 dB/1V)
Weight: 450 g.
Clamping force: low/medium
Accessories: 2 cables,  high quality presentation box for transport.

Sound description:

A short sound description would be: VERY realistic sounding, effortless. Very clear sounding with a soft yet not subdued treble. I would perhaps say the treble may be very slightly (and tastefully) elevated.
The sound is very dynamic and has an almost? unparalleled realism to it.
Bass is punchy and tight and well extended. Mids sound ‘laid back’ yet very real and are forward enough with a proper amount of clarity.
For well made recordings it sounds just right. For pop music it may be lacking slightly in body as this type of music often asks for slightly elevated bass response.

What’s quite amazing that the seal does not have much impact on the amount of bass.
With a broken seal the sound character changes slightly but bass quantity remains about the same. This is good news for people wearing glasses or having boney face structures.


Below the frequency response of the Susvara (Left, Right)

FR susvara

The frequency response shows a neutral tonal response till  1kHz. Bass as well as sub-bas is there and of high quality.
The actual measurement is perfectly flat from 10Hz to 1kHz. It would thus appear as though the bass area is reduced but this is caused by the compensation used.
A horizontal line shows a perceived ‘flat’ response, not a measured flat response.

While the mids are quite neutral it does (very slightly) lack some ultimate ‘clarity/presence’.  To see it in a more positive way it sounds slightly ‘laid-back’. The dip around 2kHz is responsible for this. That dip is smaller in reality than it measures because the so-called Concha-gain will make this measured dip smaller than it looks. It is still there though, just not audibly as deep as the plots suggest.
A dip in this part of the frequency range is more desirable than a peak.
Treble extension is excellent. It goes well beyond 30kHz. The treble sounds detailed and ‘smooth’. Maybe a tad to ‘airy’ for some people. To me the very slight emphasis is just right.

The channel balance is excellent as usual with most HIFIMAN headphones. The tonal balance is ‘flat’ as in neutral.

This headphone is more or less replacing the HE-6 so a comparison between these 2 headphone is logical.
Comparison of HE-6 (early 4 screw) vs Susvara (1/24th octave smoothing is applied).
Susvara vs HE6 4scr

One of the ‘gripes’ some people had with the HE-6 was that it had too much ‘clarity’.
The Susvara does this a bit better as the frequency range between 1.5kHz and 3kHz is responsible for this. As this is lower in the Susvara the headphone sounds a bit more ‘relaxed’, a bit smoother.

Below another ‘logical’ comparison between the Susvara and the HE-1000.Susvara vs HE1000

These headphones have a LOT more in common than the HE-6 and Susvara. Treble of the Susvara has less peaks and dips and is more linear and thus of higher quality.
There are differences well over 2 dB at various frequency bands so even though the plots show the overall tonal balance is comparable there certainly are audible differences between these models.

Below the distortion measurements of the Susvara (Right channel).

Note that this headphone was measured at ears-unlimited-logo where background noises were present in the demo room. As this is an open headphone the distortion levels and spectrum plot performance may thus be better in reality than as shown on the plots due to ambient sounds being measured along with the headphone.Dist Susvara L

Please ignore the spikes in the lowest frequencies. These are actually mains hum present in the portable measurement set-up. These spikes are NOT there in reality.
The distortion levels are very low. Below 0.5% in the lows is really excellent.  The peaks around 4kHz don’t exceed 0.5% which is not high enough to become sound degrading.
The 2nd harmonic distortion is most likely lower than the 0.2% shown in the plots. This is due to the limits of the measurement rig which is being reached

Below the distortion plot but displayed in percentages.Dist Susvara L percent

Below the CSD of the Susvara. (Left and Right are superimposed)CSD susvara

At 4kHz there is a substantial resonance 5kHz. Around 3 to 4kHz ringing isn’t very problematic as the ear-canal resonates at that frequency as well and the brain ignores this ringing as such. There is some short lived ringing around 10kHz. For an orthodynamic headphone this CSD looks pretty good. It has a lot of resemblance to that of the HE1000

output resistance / damping-factor

As this is an orthodynamic headphone its impedance is as good as ruler flat so a higher output resistance amplifier will have no consequences for the frequency response/tonal balance/damping. So… no plots as it would only show one green line.

Below the spectrum plot of the Susvara.

SPectr Susvara

Well, this looks like a mess where one wonders how audible this all is. The observant folks amongst us will notice that the green parts are down -20dB and the blue parts are already -40dB down. This means that the signal doesn’t die out as fast as with dynamic headphones. This behavior is seen with a lot of ortho dynamic headphones.
In some circles people find ortho headphones (including electrostats) have compressed dynamics in the sense that the decay of instruments isn’t as good as that of dynamic headphones. Well.. this could be the smoking gun for that theses.
It looks like these large membranes that have little to no acoustical/mechanical damping  simply LIKE to vibrate at almost all frequencies once a signal has stopped.
Around 900Hz and 4kHz and somewhat at 10kHz there is some ringing visible.

The step response (Right channel) below shows the sub-bass is just very slightly rolled-off. The higher frequency resonances directly after the initial rise are short lived and not high in amplitude.  Impulse response is at the proper level and shows excellent qualities with a only a slight emphasis in the treble. It thus sounds very clear and articulated and smooth. You can still see some medium frequency wiggles in a low amplitude on the horizontal trace which shows the lingering discussed above around 4-5kHz.
step Susvara L


Fit and finish, comfort, weight (for an ortho) are top notch. The Susvara looks really nice.
The sound signature is ‘clean’ and ‘realistic’. Slightly lacks in ‘grunt’ but sub-bass is still heard and impresses if recorded loud enough. Treble is smooth, realistic and not splashy nor sibilant at all and very detailed.

An excellent (perhaps exemplary) sounding headphone. It comes at quite a price though but you get a great looking and sounding headphone in return.

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