HIFIMAN Susvara Headphone Review

[amirm]

Firstly, this shows the weakness of the FR measurements you make to evaluate the headphones, if they change by one milimeter.

Not to a human.

 

[Sengin]

Nice, I will look into using some VST with APO to mess with phase. Do you know more free (or cheap) VST plugins that can do that besides MFreeformPhase?

Unfortunately I don't. I'm sure there are a handful out there though - let me know if you find some. Part of the issue is that the option of applying different filters to each channel separately (left, right, stereo, mid, and side) is typically not part of free effects (I don't think MFreeformPhase lets you). E.g. I use fabfilter's Pro-Q for the width trick I mention, but annoyingly there is no all-pass filter available in Pro-Q - you'd have to go to their Volcano for it. So you'd likely need to split the signals into 2 (one L and one R), send them to differently-configured effects, them combine them again.

Edit: nevermind, looks like APO has all pass filters based on your edit, that's awesome.

If you want to try out crazy spatial stuff, get the free Sound Delay by Voxengo (https://www.voxengo.com/press/voxen...-latency-delay-free-audio-plugins-update-303/) and delay the mids only (which changes the phase of every frequency by a different amount per-frequency but only on the mid channel - after all, delay is phase change). Even a 1ms delay on the mids can introduce some crazy spatial stuff - e.g. even with headphones you can make it sound like the sound is coming from behind you instead of inside your head).

 

[Blockader]

Exact same output between two headphones through the designed filter for the same given input.

Headphones are most of the time min phase systems. They take EQ well. As long as the driver has low distortion and exhibits min phase behavior(no cancellations in the response for example), they can be EQ'd easily.

It is not hard to make different headphones sound same on the same ear canal.

It is hard to make different headphones sound same regardless of the acoustic impedance of the ear canal of the individual.

The real issue with creating headphones that sound identical isn't primarily about the driver technology or the technical aspects of the driver, but rather it's largely due to the differences in Head-Related Transfer Function (HRTF) among individuals.

Put a mic next to the eardrum, and measure the FR of the incoming sounds from each headphone. They can be EQ'd to each others targets easily as long as they have min phase behavior. 99% of headphone drivers are min phase in the audible range.

 

[majingotan]

I think it's also important to note that there is another option: if the cheaper option that adheres to the target FR (e.g. Harman) is also tunable without distortion, then you could add EQ to match your preferred target* and save money.

Susvara is a linear impedance headphone so there’s no FR change by using a SET amp. The distortion from effect box added 2nd order harmonics to 5%THD overall which made the tone perceived as thicker without altering the FR of the headphone. The output impedance of the amp is roughly 2-3 ohms (for an 8 ohm output transformer secondary winding) and as such the damping factor 15-20 to 1, more than enough to not alter Susvara’s FR whatsoever.

Best part is I can use any source and get all that non high fidelity tweaks without being tied to a specific hardware, specific OS and specific software.

 

[usern]

What you can do with Equalizer APO to shift phases:

open C:\Program Files\EqualizerAPO\config
create text 3 text files:
phase.txt with content

Include: phase_left.txt
Include: phase_right.txt

phase_right.txt with content

Channel: L
Filter: ON AP Fc 290 Hz Q 2
Filter: ON AP Fc 590 Hz Q 2
Filter: ON AP Fc 1000 Hz Q 2

phase_left.txt with content

Channel: R
Filter: ON AP Fc 250 Hz Q 2
Filter: ON AP Fc 520 Hz Q 2
Filter: ON AP Fc 900 Hz Q 2

Open up Equalizer APO, click green + sign -> Control -> Include and write phase.txt in the text box there
Now you can toggle on and off the messy phases and adjust the left and right channel filters

I eyeballed the frequencies from frequency response measurement graph

If Amir shared numerical data on group delay measurements for both channels, then perhaps we can create config that simulates Susvara built in effect if indeed Hifiman has deliberately used this technique.

 

[192kbps]

No one is aiming to model a headphone. We are trying to estimate its tonality and we can do so with high level of success. Indeed a lot of Harman research was performed by using a surrogate headphone to emulate the frequency response of other headphones. Before running with this, they verified the efficacy of the method:

View attachment 337307

As you see, the surrogate headphone equalized to the real headphone's response produced statistically even preference from listeners in controlled tests.

So both in theory and matter of actual testing, your assumption is wrong here.

Beyond tonality, the problem gets hard but tonality is so important and fundamental to headphone performance.

I have always had a question, why can't all three low-frequency preferences of the Harman curve be displayed in the chart?

 

[Sengin]

Best part is I can use any source and get all that non high fidelity tweaks without being tied to a specific hardware, specific OS and specific software.

Absolutely. You can't, however, turn it off, and that's important to keep in mind. Let's say a new song comes out, and the artist has taken deliberate time and effort to make the high frequencies shift about in a pleasing way (in more specific terms, passing this song through a goniometer https://en.wikipedia.org/wiki/Goniometer_(audio) will show a width greater than a full hard pan left or right, and that width changes/shifts over time). This headphone, with its current response, will interact with that careful effort and may sound worse (assumption: susvara has variable phase changes in the higher range).

I'm not saying that this is absolutely a downside, but just something to keep in mind.

 

[amirm]

I have always had a question, why can't all three low-frequency preferences of the Harman curve be displayed in the chart?

Because we want to have a single standard. Multiple standards is an oxymoron. From the research paper on this:

"Notwithstanding these factors, the authors believe that a
new standard headphone target response based on one
of the target curves shown in Fig. 13 would help
advance the consistency and sound quality of consumer
and professional headphones."

 

[the_brunx]

Why waste resources trying to separate the sound of your flagship model to your entry level offerings when you can just use different cups and solder the cables the wrong way to reverse the polarity and make them sound interestingly different. Genius!

 

[IAtaman]

I have always had a question, why can't all three low-frequency preferences of the Harman curve be displayed in the chart?

Amir chooses not to for his own reasons, it does not mean it can not be done. There are a few places that do show the natural variation in preference found in the study as boundaries.

I was, and still am to an extent, proponent of the idea to show the preference variations not for bass only but for the overall range. One fair criticism of this approach however is that if you were to pick a high bass low treble option for yourself for example, you will still be within the "boundaries" of preference deviation, but you would have tilted the balance in one direction so much that the overall spectral balance would be too far away from "neutral".

And if you do if for bass only, you have the same problem. There is this perception that the way to achieve more spectral balance is to fill in as many holes in the FR graph as you can. That is not correct. If you add a bass boost to an already bass tilted headphone (e.g. due to holes in treble), you'd actually be moving it away from balance, not close to it.

 

[Madlop26]

Amir chooses not to for his own reasons, it does not mean it can not be done. There are a few places that do show the natural variation in preference found in the study as boundaries.

I was, and still am to an extent, proponent of the idea to show the preference variations not for bass only but for the overall range. One fair criticism of this approach however is that if you were to pick a high bass low treble option for yourself for example, you will still be within the "boundaries" of preference deviation, but you would have tilted the balance in one direction so much that the overall spectral balance would be too far away from "neutral".

And if you do if for bass only, you have the same problem. There is this perception that the way to achieve more spectral balance is to fill in as many holes in the FR graph as you can. That is not correct. If you add a bass boost to an already bass tilted headphone (e.g. due to holes in treble), you'd actually be moving it away from balance, not close to it.

“For his own reasons”?? Amir use the curve that the research recommended, period, why to graph the outliners?, and can anybody explain the rest of the comment, it did not make any sense to me as many of his previous comments, it’s becoming so tiresome.

 

[amirm]

“For his own reasons”?? Amir use the curve that the research recommended, period, why to graph the outliners?, and can anybody explain the rest of the comment, it did not make any sense to me as many of his previous comments, it’s becoming so tiresome.

The rest of the comment explains the point I have made to him: that if you put a band around the target, a headphone could be in that gray area in bass at the peak, and lowest in treble. This is wrong as the bass response was associated with a certain treble response, not independent of it.

 

[Brubaker]

I am truly amazed at how much criticism has come for this measurement. This morning too I'm listening to the 800s which are good headphones but they become better when I equalize them on the Harman, removing an annoying peak on the highs and increasing the bass until they reach the desired level without distorting. I accept this..this is Simply the Truth....I do all this work thanks to a free app and to people who have made time and equipment available to measure thousands of headphones. I also measure headphones with modest equipment and I know how complicated it is to obtain a good result, it takes time and accuracy. I've tried dozens of configurations but in the end I always come back to the Harman. I apply equalizations to any headphones and try to get the best from each one. So I discovered that by equalizing a Grado SR80X I get an overall result that I like more than the Sennheiser 600 and similar. In the end what I find different between the various headphones is the sensation of three-dimensional sound or that it moves more or less away from my head. In the Grado or 800s it is better than many other headphones that have a frequency response closer to Harman. So I can get the best results using free equalization software. This thing is fantastic but can you really not accept that you can make 100 euro headphones or thousands of euro headphones sound better in the same way? Those who try to make headphones sound different by spending thousands of euros on esoteric cables and amplifiers make me smile. The revolution is within reach of any pocket, it is the proofing software and it is free. Obviously those who spend thousands of euros on expensive cables will never accept it and know nothing about measurements and correction applications.... how could they write dozens of pages on the nuances and delicacies of a violin reproduced by the susvara compared to a modest Fidelio equalized.... get over it, with 100 euros and an App today you can listen to music with great sound quality. In the case of Hifiman I really don't see the value of 6000 euros... the materials are the same from 300 to 6000.... it really seems like a bad deal to me... I would gladly try an Edition Xs with some EQ... have a nice Day... my 2 cents

 

[Thl]

you must be kidding...
this forum must be something like the Truman Show, you really can't be people listening to music

 

[ObjectiveSubjectivist]

We are the plebeians that cannot appreciate the sound. Real HARDCORE audiophiles have sophisticated taste that is unobtainable for us mortals.

 

[Scott_Williams]

Nice review as ususal, I really wish I could enjoy it too but it's too expensive for me

 

[IAtaman]

The rest of the comment explains the point I have made to him: that if you put a band around the target, a headphone could be in that gray area in bass at the peak, and lowest in treble. This is wrong as the bass response was associated with a certain treble response, not independent of it.

You did indeed, and you were right.

I still think however it is a good idea to show that different tunings might be as valid as well to bring more people around the science instead of insisting on one truth at the risk of alienating people. I am not sure what would be a good way of doing that though.

 

[Jimbob54]

you must be kidding...
this forum must be something like the Truman Show, you really can't be people listening to music

Just test tones and sweeps here mate.

Anyway, what's your point?

 

[Sokel]

you must be kidding...
this forum must be something like the Truman Show, you really can't be people listening to music

What kind of music do you listen to?

 

[amirm]

you must be kidding...
this forum must be something like the Truman Show, you really can't be people listening to music

Seeing how crazy wrong it is to say another audiophile doesn't listen to music, we know how much you value reality.