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Hifiman HE400i Review (planar headphone)

ehabheikal

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Unless you've rooted your phone, system-wide parametric equalizer software for Android isn't possible, in which case I'd recommend the excellent Qudelix 5K USB DAC/amp with its built-in 10-band parametric equalizer (and optional Bluetooth connectivity as a bonus).


actually buying a used lg phone and rooting it would be a very good alternative
 

Jimbob54

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I found out bubbleupnp app not the server plays all file types and qobuz and tidal and allows common equalizer apps to work with it. I use wavelet since it has database of headphones for correction if you have the bubbleupnp server installed locally it also streams like roon
UAPP would be a good all in one alternative if you haven't already bought neutron /bubble.
 

pwjazz

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actually buying a used lg phone and rooting it would be a very good alternative

I've done this and did system wide EQ with Viper4Android. I also own a Qudelix. I can definitively say the user experience with the Qudelix is orders of magnitude better than rooting and then trying to get Viper4Android to work right. Also the Qudelix has two of the ICs from the LG phones for more power in balanced mode. I find that with my EQ and replay gain settings, the HE4XX needs the extra power.

Since getting the Qudelix, I haven't used my rooted V20 at all.
 

Robbo99999

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Anyone else notice that their HE4XX (or HE400i) sounds better after a warmup? What I mean is I'll put the headphone on and listen to a couple of parts of a couple of tracks I know very well as soon as I put the headphone on....just to kind of quickly acclimate to the headphone, and it'll sound good/ok, but then I'll play an fps gaming session using the headphones for an hour or so, and then I'll listen to some music afterwards, and it's this music listening session after the gaming where it sounds fantastic.....like the headphone has loosened up and sounds smoother (whilst retaining detail) as well as having deeper rounder more pronounced bass.....my theory is that wearing the headphone warms up the drivers and changes their properties.....I also have made a loose connection that they may sound better since my room has warmed up over the last week or so (talking a change from say 17 degC to 21 degC).....but they always seem to sound better after I've been wearing them for an hour or so (independant of room temperature). What you think, you noticed this phenomenon with your planar driver headphones?

I know that with some KEF speakers there was a debacle over low room temperature affecting the bass response in the drivers, so perhaps this carries over to headphones to some degree, and perhaps more so to planar driver headphones, as it's not a phenomenon I've noticed as pronounced with my other headphones which are all dynamic drivers.
 

dorirod

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Maybe the pads have warmed up? I haven't noticed a big difference, but I'm not sure I have that critical of an ear. If I were you I would take notes on the initial tracks you find lacking and the subsequent tracks you find sounding better and see if it's more a track difference.
 

Robbo99999

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Maybe the pads have warmed up? I haven't noticed a big difference, but I'm not sure I have that critical of an ear. If I were you I would take notes on the initial tracks you find lacking and the subsequent tracks you find sounding better and see if it's more a track difference.
It's a general improvement on the tracks I use to benchmark different EQ's (so I know them well). I don't think it's pad related as the pads on the HE4XX are very soft, so I can't really see them deforming significantly more over an hour say.....so it seems like it's driver temperature related - time for the drivers to warm up from the heat of my head and the correlation I made to room temperature sits with this too, although the latter effect seems less pronounced.
 

Robbo99999

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@amirm , might be an interesting experiment to measure some planar and dynamic driver headphones at some different temperatures.....like perhaps keep the measuring unit & headphone in the shed in the garden for a low temperature reading, and then try it again in the warmth of say a 22 degC house (once both headphone & rig have warmed up to that temperature). Then as a third option you could wear the headphone for say 1 hour to warm it up and then measure it immediately afterwards to see the effect of warming it up from body heat........see if there's any difference in frequency response or distortion. You found a temperature related effect with a KEF speaker a year ago (or months) so perhaps there's a similar behaviour in headphones......and operating temperatures of headphones could range from the coldest rooms (15 degC or less and especially if using outside) to the warmest at around 30degC+ in the summer.
 

Jimbob54

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It's a general improvement on the tracks I use to benchmark different EQ's (so I know them well). I don't think it's pad related as the pads on the HE4XX are very soft, so I can't really see them deforming significantly more over an hour say.....so it seems like it's driver temperature related - time for the drivers to warm up from the heat of my head and the correlation I made to room temperature sits with this too, although the latter effect seems less pronounced.

Nope - far , far more likely its ear/ brain related. Rule out those first then investigate physical changes.
 

Robbo99999

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Nope - far , far more likely its ear/ brain related. Rule out those first then investigate physical changes.
I can't rule those out though, which is why I came up with the idea in my previous post for Amir to measure it. It's gotta be measured to know.....I've noticed a difference, but there's no way I can rule out psychological influences otherwise.
 

keebz28

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@Robbo99999 I haven't observed the same phenomenon as you but have noticed that the HE4xx definitely take a lot more juice on my headphone amp to get audible. My 320ohm Frankenphone can be audibly loud at 9pm on the JDS Atom compared to a full 12 oclock for the HE4xx which are 32ohm. I am uneducated in the technology world so i maybe misinformed.
 

Robbo99999

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@Robbo99999 I haven't observed the same phenomenon as you but have noticed that the HE4xx definitely take a lot more juice on my headphone amp to get audible. My 320ohm Frankenphone can be audibly loud at 9pm on the JDS Atom compared to a full 12 oclock for the HE4xx which are 32ohm. I am uneducated in the technology world so i maybe misinformed.
About driving the HE4XX, it's pretty much as easy/difficult to drive as my K702, I use them both around about the same volume dial position on my JDS Labs Atom amp (taking into account the slightly different negative preamps used). The same is true for my 300ohm Sennheiser HD600, all pretty much the same I've found re difficulty of driving them. So the HE4XX is not that easy to drive, but not overly difficult.
 

Jimbob54

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I'm glad you like it, we can thank Oratory! I know, I was quite surprised by how it transformed these headphones, to be fair I haven't flipped between my different EQ's to compare in a back to back manner, but I'm quite sure they never had the overall clarity & smoothness that this EQ gives.

Well, I have set up the "new" EQ . Im not sure how he squares the 2 EQs. Latest is a couple of db more bass in the very bottom end and taking out the 6db high shelf has the overall effect of knocking all the 8k plus down by 6db or more - so very different presentations . The fact the pre amp reduction has increased a couple of dB makes a quick A/B switch pretty impossible. Im not sure how I can compare the 2. They are decent headphones with either EQ or stock but they never wow me. The new EQ has more bass than I would ideally want, as does the old and I still struggle to engage in the music with them .
 

bobbooo

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The fact the pre amp reduction has increased a couple of dB makes a quick A/B switch pretty impossible. Im not sure how I can compare the 2.

Then set the preamp of his original EQ profile to the same as his new one (-9 dB).

The new EQ has more bass than I would ideally want

Oratory's new EQ format includes broad shelf/peak filters covering different frequency ranges to adjust to preference, as is clearly displayed on his new HE4XX pdf:

Screenshot_20210305-180416_Acrobat for Samsung.png
 

Jimbob54

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Then set the preamp of his original EQ profile to the same as his new one (-9 dB).



Oratory's new EQ format includes broad shelf/peak filters covering different frequency ranges to adjust to preference, as is clearly displayed on his new HE4XX pdf:

View attachment 116388

On the former, good idea, not sure why I didn't think of that. On the latter, yes. I much prefer expressing there is a range one can use. Though if course that's always been the case for any EQ.

I'm fairly sure the main difference between new and old here though is the 6db extra treble from 8k onwards in the "old" due to the high shelf. As to which is "right", I know not.
 

Robbo99999

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Well, I have set up the "new" EQ . Im not sure how he squares the 2 EQs. Latest is a couple of db more bass in the very bottom end and taking out the 6db high shelf has the overall effect of knocking all the 8k plus down by 6db or more - so very different presentations . The fact the pre amp reduction has increased a couple of dB makes a quick A/B switch pretty impossible. Im not sure how I can compare the 2. They are decent headphones with either EQ or stock but they never wow me. The new EQ has more bass than I would ideally want, as does the old and I still struggle to engage in the music with them .
I didn't like his previous EQ because of that large High Shelf Boost that was left north of 10kHz, so I used to use my own EQ based on his measurement, however I like his new EQ better than my own EQ, so I'm using his latest EQ now. And as bobbooo points out his latest EQ has some broad range customisation filters that you can tweak the curve to your own enjoyment - it's quite clever how he's been able to work those customisation filters into the EQ whilst still only using 10 EQ filter bands. I've not felt the need to tweak his customisation filters yet though, I'm just using his EQ at stock so-to-speak. If I was gonna mess with one of the bands it would be Band 5 which he lists as Upper Mid Accuracy/Shoutiness....I think this is one area where the Harman Curve might differ from my own HRTF, but not significantly so I haven't played with that variable yet.
 

Jimbob54

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I didn't like his previous EQ because of that large High Shelf Boost that was left north of 10kHz, so I used to use my own EQ based on his measurement, however I like his new EQ better than my own EQ, so I'm using his latest EQ now. And as bobbooo points out his latest EQ has some broad range customisation filters that you can tweak the curve to your own enjoyment - it's quite clever how he's been able to work those customisation filters into the EQ whilst still only using 10 EQ filter bands. I've not felt the need to tweak his customisation filters yet though, I'm just using his EQ at stock so-to-speak. If I was gonna mess with one of the bands it would be Band 5 which he lists as Upper Mid Accuracy/Shoutiness....I think this is one area where the Harman Curve might differ from my own HRTF, but not significantly so I haven't played with that variable yet.

Stick a 6db , Q0.7 8khz high shelf on his new EQ, set both EQ to -9db pre amp and tell me you can hear a difference apart from maybe a touch more low end on the new one when you quick A/B.

I think he changed his mind about the high shelf and re-jigged the rest of the filters to make it essentially the same apart from that high treble boost and a bit more at the very bottom.

All EQ profiles have always had the ability to tweak for preference , he is just articulating what the impact is now , I dont believe he is designing them to be more customisable.

EDIT- oh, and stick a 2dB high shelf as above to new and I prefer new to old, but without the extra treble, new EQ sounds a bit dull.
 
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Robbo99999

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Stick a 6db , Q0.7 8khz high shelf on his new EQ, set both EQ to -9db pre amp and tell me you can hear a difference apart from maybe a touch more low end on the new one when you quick A/B.

I think he changed his mind about the high shelf and re-jigged the rest of the filters to make it essentially the same apart from that high treble boost and a bit more at the very bottom.

All EQ profiles have always had the ability to tweak for preference , he is just articulating what the impact is now , I dont believe he is designing them to be more customisable.

EDIT- oh, and stick a 2dB high shelf as above to new and I prefer new to old, but without the extra treble, new EQ sounds a bit dull.
His EQ wasn't customisable in the same way before, there are more specifically designed customisation filters on his new EQ (EDIT: having looked at his old EQ just now he does have some very similar filters that are close to the same as the customisation filters he uses in his new EQ, but the High Shelf filter he used on his last EQ wasn't really customisable because it kicked in way to low down in the frequency range, and I also think the Q Factors and Frequencies he's chosen for his customisation filters this time are a bit more optimal for their intended usage albeit quite similar). The measurement is also slightly different than he used before, I haven't compared as accurately as overlaying the new measurement vs old measurement, but for sure he has at least smoothed the measurement (or maybe even measured a few more headsets and averaged them). It's alright, I won't do the tests you're suggesting, I'm not that interested in it, I prefer his new EQ.
 
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Ruben

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This is a review and detailed measurements of the Hifiman HE400i planar magnetic headphone. I purchased this back in 2017 mainly to test headphone amplifiers. The latest version which I am told is different costs US $185 from Amazon including Prime shipping.

The HE400i is quite light and fits quite well on my head:

View attachment 100131

The stock cord is removable which is nice. As is though, it is stiff, rather short and comes with that odd right angle 3.5mm headphone jack. Seems like they assumed people would be using this in a portable application. For my desktop use all of these are aggravations. I have to use a 1/4 inch adapter with it and the right angle cord gets in the way of my controls. The short cord has also pulled the headphone off my head in more than one occasion.

Here is a zoomed picture of the cup with no informational value:

View attachment 100132

The measurements you are about to see are made using a standardized Gras 45C. I searched for any and all measurements I could find online. Alas while a number of them are close to mine, none are using the exact fixture down to coupler and pinna. As you will see, I have confirmed the approximate accuracy of the measurements using Equalization and listening tests. Ultimately headphone measurements are less exact than speakers above a few kilohertz so keep that in mind as you read these tests.

I have calibrated my headphone fixture with 94 dBSPL test tones and decided that I use the same for headphone measurements. However, instead of using 1 kHz tone I have opted for 425 Hz. This seems to better match research data.

I have also made a lot of progress in building a better test suite for the measurements. More updates and changes will be coming but I am starting to feel good about this set.

Hifiman HE400i (2016) Measurements
There is nothing more important than frequency response of the headphone as each is seemingly different and that difference leaves a very distinct character:

View attachment 100133

The ASR preference curve is in sold dashed blue. The red and green are each channel. Matching is pretty good. What is not good is cheating us out of a lot of energy in the all important region of 1 to 3 kHz. Why oh why? This is a common theme among many headphones it seems.

As is usual, bass energy is lower than our target although not as bad as some others I have tested.

What is unusual is all the kinks and noise in the graph. Transfer function of the headphone must be changing in complex ways to create these. Indeed looking at the distortion curve shows us some of this:

View attachment 100136

Someone post that the HE400i is one of the lowest distortion headphones out there. I sure hope not given the above performance! Here is the same data but shown as absolute distortion level rather than percentage:

View attachment 100141

I have picked the 40 dB as my tentative threshold level. As we see bass distortion is quite good but we have peaking around 400 Hz and 1.5 kHz.

Oh, in case some of you have trouble reading the frequency response chart and want a more "speaker like" frequency response, here it is:
View attachment 100138

I use this graph for equalization. Be careful in the troughs toward the end. Do not try to boost those as they are likely cancellations due to reflections inside the cups. We can see this in the group delay graph:

View attachment 100139

Notice how the frequency response errors between 200 and 300 Hz are repeated here.

I made quick fixture to measure impedance (better one to come soon when I get the precision resistors I ordered):

View attachment 100142

Note that the above display is highly zoomed. Otherwise it would look like a flat line which planar magnetic drivers are known for. As zoomed, the peaks are dependent on how the headphone is mounted. On my head they were lower in frequency than on the fixture.

Hifiman HE400i Headphone Listening Tests
As is, the headphone has a rather "open" sound but nowhere near the spatial effects that the Sennheiser HD800S had. The sound is compressed around a grouping close to my ears. Tonality seems rather dull and closed in. So comes out the EQ tools:

View attachment 100145

Wow, what a difference this made. The sound is now impressive with fantastic dynamics and very clean bass. Detail is improved substantially. On my "speaker killer" tracks without EQ, I could hardly hear the deep notes. With EQ on they came to live without the overall tonality sound like "too much bass." Note how I am lifting the frequencies below 50 Hz or so. It is a bit like adding a subwoofer, not boosting the lows in your speaker. With EQ, I now get deep bass performance that simply does not exist in any bookshelf speaker.

Tracks like Artillery Infected Mushroom sound so much more live with EQ that you can't help but want to bob your head and band on the desk in unison!


Then we swing to the other extreme with Kristin Asbjørnsen's wonderful track, Rain, oh Lord:


As for the distortions we saw in the graphs, I could tell you that I hear them but I am not sure at all. The highs sound a bit shrill at moderate levels. Turning the levels up accentuates this. But this could just be me not trying to EQ above 8 kHz. A shelving filter may help there.

Conclusions
This review was prompted by a member suggesting that the Hifiman HE400i can present that interesting spatial quality that the Sennheiser HD800S. Alas, that is not the case. Maybe there is a hint of that but not more. The frequency response of HE400i shows more bass response which is good but also less energy in the important 1 to 3 kHz region. EQ therefore is mandatory to restore proper balance, resolution, deep bass and detail. Once there, this is a new headphone, producing a very enjoyable experience.

Until I did this test and developed the EQ that you saw, I rarely used the HE400i But now, I am actually anxious to listen to it more! I can't get over how "high fi" it sounds with equalization! :)

I will give the HE400i a pass without equalization. With EQ, I am happy to give the Hifiman HE400i a recommendation.

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As always, questions, comments, recommendations, etc. are welcome.

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Hi, I love your review and thanks for this eq settings that share. I'm from Romania, have 43 age old and I love good music. I brought yesterday a pair of Hifiman 400i 2020 and his sound is more more better with your eq implemented. I paired the headphone with îmi micro idsd Black label via laptop and Fiio q1 Mark 3 via Android. For laptop I use Jriver and for Android Uapp.
 
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