Headphone filter rolling

Reaching out to those on the forum into headphones…
I have been getting into headphones this year, and learning a lot with respect to home audio…
One of the things I have learnt is that the best sounding in terms of musical and emotional feel means they have a contoured frequency response, often approximating to the Harman curve…

That is all well and good, and coupled that we all hear things, or more accurately focus on different elements in the audio and music.

Now we therefore find every headphone can be tweaked to match the listener… for max musical / emotional involvement.

One can use expensive analogue parametric equalisers, or luckily using digital filtering it’s a lot easier and cheaper to do with optimum SQ.

Now I have been experimenting with different amps and headphones… right now I am listening to a Chord Dave… and I am not sure it’s the best for driving magnetic planars such as Meze Empyreans but dynamics it seems to work perfectly such as Utopias and HD650s.

Right now I really think the DAVE drives the 650s perfectly… it sounds so natural with out any distracting artefacts… but I have rolled a filter to adjust the sound to how I like, no doubt to years of listening to ATC standmounts, using the Roon integration with my NDX2.

The filter looks like this…

This only works well with DAVE and the HD650s… but works wonderfully across genres, albeit some 30Hz slam on the open backed dynamics is muted, but is tuneful… you can follow the tuning on some EDM bass drum… fantastic… albeit the slam is there on mag planars…or closed backed dynamics, but perhaps not quite as resolved. But now 650 sounds like a headphone many times it’s price… it really scales tremendously well.

Has anyone else got similar experiences rolling filters for specific headphones?

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Not tried anything with headphones, as I only use for travel, not particularly high quality ones - though i am contemplating buying some headphones for sociable hifi listening at times in the future (would have to be closed back to do that).

I have oft thought that DSP appropriately applied makes a lot of sense, given that speakers/rooms - and indeed headphones - in practice are often far from perfect, while also we may all have different preferences for sound. An additional function could be ‘loudness’ compensation for low level listening. Having a digital crossover with some spare DSP capacity I do apply a little, though actually to even out some peaks and minor dips in response - but aiming for as flat a response as possible, though not dead level, factoring in a gentle upward slope toward the bass end, mimicking what I understand is a natural room response. I have never tried tweaking in a more dramatic manner.

What do you use to apply the DSP filtering?

Hi I use Roon… to eq the sound.
Yes room response has a slight declining treble from around 2k and slight bass boost from 150 Hz down, so ideally you don’t usually want to eq against that.

With headphones things get really interesting, as the headphone response is usually mapped to the Harman curve (For music) and want to eq in association with that to suit how you like to have audio presented.

Real audio for humans is far from flat…if you want it to sound natural and not artificial.

Real music indeed is, but if (big IF!) it has been recorded neutrally, then playing back through a system that is neutral - i.e. flat in this context - should produce the sound that was in the studio. Unfortunately most things are less than perfect…

Yes indeed… music is mastered using monitors or headphones, and you can indeed sometimes tell whether it was a treble or bass strong mastering system or the preference of the mastering engineer.
So electronically I guess it’s best to keep things flat, until you want to modify the sound to suit for a specific headphone response, or speaker room interaction… unless of course you are listening with same headphones or near field monitors that were used to master.

I’ve tried filters specifically created for certain headphones from AutoEq he collates a bunch all using diffferent measurements etc. But not bothered with my own, generally quite happy as they are and seldom use even these. They took the whole fun out of my Meze 99’s as they are not meant to be flat, it’s what makes them a fun listen.

Now I use the RME DAC as my main headphone listening and it has its own inbuilt EQ and has a selection of filters like the Chord DACs, I mean to get round to using these instead of Roons at some point.

Funny you should mention loudness compensation, my RME has this and it’s fantastic for low level listening. Its one of the DACs many strong points as their implementation is very good. It also manages it based on the listening level so adjusts it as you go up in volume. You can set the parameters as to what range it works in or just use their default, which is perfect anyway.

Hi, yes I was only with a very resolving DAC/amp did I discover the benefit of optimising to suit my hearing. Apparently there are some weird things that go on with hearing such as masking and that can vary from person to person… our ears and specifically our auditory canals are quite unique.

I think this phenomenon is more common than some perhaps realise. You often read about somebody finding x more detailed than y, when actually it’s the same signal with an ever so slightly different FR… the details are present and the same in both.

For what it’s worth, and I am not familiar with your DAC, but the Chord filters are for warm or neutral, and intermodulation distortion filtering. These are very different to optimising for our hearing response in my experience.

But it is interesting how a couple of dB boost or cut at a certain spot around the mids can have a massive difference to the feel of a set of ‘phones and their apparent detail resolution.

The RME is a very resolving DAC and works well with the Focal Elears I use with it but I know I can get it better with tweaking eq just not got there yet. The filters I mentioned are not related to EQ they just DAC filters, SD Fast, SD Slow, Fast, Slow, NoS, etc. I just use the default SD Fast as I honestly cant hear much difference between them they are so subtle.

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Hi Simon, I haven’t tried it yet, but this guy does good YouTube headphone reviews with and without EQ, and puts the settings that he has found work best into the show notes of the review: https://www.youtube.com/channel/UCt44wdefZzrhNDYYAyEy3Xg
He did one this week trying different ear pads with the Focals, and the EQ that he found was best with them. His opinion is that no headphone has a perfect frequency response, but by tweaking these settings, you can get rid of most of the nasties, and apply a more pleasing effect. Hope that is useful, cheers.

To be properly effective, ‘loudness’ compensation should not just be an on or off, but should increase as average sound level of a recording is decreased, which would be different for different amp/speaker/room or amp/headphone combinations. It should not be difficult these days for DSP software to be designed to set up semi-automatically in-room using a measuring microphone, to thereafter by controlled by a link to volume control setting - I wonder if anyone will?

Hi, I use the library on github under AutoEq… but only as a guide… I adjust to suit.
Yes headphones exaggerate the imperfections in current transducer technology and design. None are perfect, and our ears react differently when critically listening…

You know when you get it right, because a voice in a mix can sound like it’s somebody standing behind or beside you… and it freaks you out… especially if not a familiar recording.

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Such a result would be far from perfect certainly for mid and trebles… you would need to have a head shaped microphone with ears and microphones in ears to provide a better approximation for critical listening in a room.

You see some lower end consumer solutions emulate this by requiring the mic to be rotated in large circles moving around the room, and the response being averaged. (Sonos and LG do this for example)

It works very well as it is adapting to the volume levels you listen to. I was sceptical before using it but now won’t listen without it.

The practical way to do it is averaging multiple measurements in the area occupied by ears in the desired (or optimum) listening position. Dirac Live used to indicate multiple positions to use for room equalisation purposes. There is a clever motorised mic that apparently can do the equivalent, though presumably not affordable for normal domestic use!

It would be trickier to do oneself with headphones than with speakers…

Yep, the advantage of headphones is that you do not need to measure the room response… you tune for your ear response.

Yep, you need the shape of your head and ears as well to be accurate, and indeed there are jigs that do this… at least so I have seen referenced in engineering papers… for me an approximation is better, and a normal room response needs to be approximated as moving a few cms could change the response in mid and treble frequencies if attempting to be too accurate.

Yes indeed - as anyone can tell if they move their head slightly when affected frequencies are playing. I find it rather incredulous when people talk about positioning speakers to better than 1 cm - unless they use a brace for their head! One key advantage of headphone must be their very repeatable positioning, and immune to head movements. Against that, a key disadvantage to me would be not feeling the bass through clothing and seat, only hearing. Maybe the answer is both headphones and speakers, for different types of listening - and with easily switchable DSP that may be realistic to do.

Well with bass slam (technically called infrasound with frequencies below around 20 Hz) then with headphones capable you do feel that on your skull as it is mostly non audible… so similar experience.
Clearly if you want to feel the sub bass pressure wave hit your chest for example, then indeed headphones can’t provide that (nor can many speakers…) … you might want to try haptic transducers in your chair to provide a greater sub bass experience :grinning:

But seriously, one thing I have learned is that in many domestic listening environments, quality headphones and amps are the way I have found of providing good deep tuneful bass and sub bass slam.
The downside, is that seemingly much music is not mastered to be reproduced accurately down there so can sound a little odd or unexpected sometimes… so I have found a sub bass shelf filter (akin to to the phono rumble filter) can be useful say with magnetic planar ‘phones.
But listen to many classical orchestral pieces, and that added bandwidth is often truly welcome.
With headphones it is nice to hear the full bodied resonances of the bass string section of the orchestra for example without any blooming or resonance from your speaker / room coupling … and it it sounds rather striking… as it makes you realise how often this is not reproduced properly in home audio.

Many years ago a friend put a large speaker cone in the base of an easy chair, effectively turning it into a sub. It wasn’t strictly HiFi, but it was fun.