Yes, only the parts that need to be addressed are targetted. With some headphones the differences are less subtle, with other headphones they appear small when the corrections are small (in the order of a few dB here and there)
It also has to do with adjustment of the brain. Those familiar with something like the Koss KSC75/PortaPro will know this effect. When you put them on they sound a little 'off' but quite quickly they sound good and after a short while longer they sound great. UNTIL you put something 'better' on your head. Then it is quite apparent the Koss isn't great. It is tonally a bit 'off' lacks bass extension etc. Yet, when you only listen to it for a while it is great.
Your brain also adjusts to other headphones and after a while you don't hear the flaws that much any more until you hear it without a flaw.
Sound with less flaws (it will always remain flawed) is easier to adjust to and when you listen for a while to that and switch the filter off again the flaws become more obvious than the other way around.
Another effect is that when (as in most cases) subbass extension is improved and a peak is lowered it doesn't always stand out immediatly in a lot of music. It becomes more obvious when you hear a glorious subbass on a level you always wanted to hear it but was always more subdued. The same is true for a peak at a high frequency for instance. That peak may only be bothersome in some recordings. That may last only shortly and we forget, concentrating on what is playing currently. After a while, when corrected, you do not notice it any more so aren't bothered... a more pleasant experience. Switch the filter off and there it is again. More annoying as you now know it doesn't have to sound that way.
In other headphones where overblown midbass is present (say MDR-1A) switching the filter on and off is VERY obvious. When you are used to that sound and kind-off like it then switching it on may appear to sound a bit thin. When you listen to it for a while and get used to it switching the filter off again makes it sound very bloated and dark. That difference is bigger and more annoying than the other way around.
For sure, I can't listen to a HD650, T50RP, DT1350, MDR1A, HD800 any more without a filter. Reason is once you have heard a 'better' presentation it is harder to live with those colorations.
use your EARS to enjoy MUSIC .... NOT as an analyzer
My experiences are similar. With the HE-560 module I initially had to check if the filtering was turned on because I really couldn't detect any discernible differences. It was only when the sub-bass kicked in on the track I was listening to and I had a holy smokes (may not be the exact word I used) moment that the the penny dropped. And then when I switched the module back off all of a sudden a whole raft of previously unnoticed little nuances start to reveal themselves and I could appreciate things better.
Which brings me on to the HE-560 and those impressions that I promised.
Really for me the HE-560 does more right than any other headphone I've owned so when I approached Frans regarding the possibility of a module I did so with a mixture of hope and trepidation. Not because I don't trust Frans' judgement but I was concerned that even sympathetic 'enhancements' might result in the headphone losing some of its character. Sometimes its those little imperfections and quirks that give a headphone its charm.
To my ears in stock form the 560 is quite a neutral and linear sounding headphone with very good treble and bass extension. Detail is excellent as is timbre. However, whilst capable of very deep bass and excellent bass quality with many recordings the quantity is lacking and it feels like the bass has gone awol. Then with other recordings, sadly too few, it suddenly rears its head and can be surprisingly powerful.
That aside the only other real complaints I have is that it sometimes has a tendency to sound a touch thin and the upper mids (or lower treble) can sound a bit peaky and grating.
After a few PMs to make sure we were on the same wavelength Frans set about making a module for me. Please note the production module may differ very slightly from mine (Frans may confirm) but I think mine has been set as follows:
+5dB added to sub bass and +2 or 3dB to the low bass
+ 1 dB at 2kHz
- 5dB at circa 5kHz (tames quite a large peak)
+ 1dB at 15kHz
Using the module the bass quantity is close to perfect to my ears. Recordings that previously sounded good don't feel like they have become overpowered but those that were a bit anaemic now have satisfying bass quantity. The bass now sounds more palpable and has great sub bass rumble. Very moreish.
The increased bass quantity also seems to have the knock on effect of influencing the wider sound too as the thinness I mentioned is no longer evident and music has much greater body / fullness to it now and seems more 'rounded' (3 dimensional) in nature. It's strange because although the width doesn't appreciably change, when I switch off the module the HE-560 now sounds really small by comparison.
Having addressed the 5kHz peak instruments that sounded a bit too sharp or shouty now seem considerably tamed but not so much that they feel neutered.
There also seems a greater sense of balance and cohesion to the sound now.
All in all I'm very happy with the changes that have been introduced and I really don't think I could go back to using the HE-560 without the filter or some form of equalisation now. I think tunkejazz is spot because although the changes are often sublte it is almost like switching from one headphone to another.
I agree Mark, you don't want the 'soul' sucked out of the headphone and as Frans says, some adapt better than others. I think you found that with the dt990 which you felt lost its character.
The effects really are subtle until you turn it off!! For me, the Senn hd650 sounds terrific once filtered, but mediocre when not filtered. It's not until you've heard it that you appreciate what the previous 'unidentified' problems were with your headphone. Suddenly, the problematic areas become very noticeable.
The Kameleon got me searching for something better than the hd650 since I can now hear its problems far too easily!!
'Soul' is a good word for it Ian. Both the HD650 and HE-560 retain their soul when filtered so you get the best of both worlds. More of the same only better. As I said to Frans a while back changes are subtle but profound.
For me personally the filtered DT990 might just have been too much of a departure from stock form but then again it's a headphone that probably needed a lot more knocking into shape than some!! Don't get me wrong it sounded great and if I hadn't had a module for the HD650 I'd have greatly appreciated having the option of flitting between the two different sounds; one flat the other fun. But when you have both it's clear that filtered HD650 > filtered DT990. No shame in that as the HD650 + module is a formidable pairing.
I have a set of HiFiMan HE500. This is my main headphone. Can anyone here tell me what their experience with the module change sounds like for this particular headphone? The only change I've made is the HiFiMan pad change (I can't remember what they're called - the pads are part velour and part pleather and slightly angled compared to stock).
My other set is a pair of HD650. I bought them used in 2010, so I'm thinking they're the older 'black' version.
I'm running iMac -> USB -> Schiit Wyrd -> Bifrost Multibit -> G1217 Polaris. I was thrilled with the DAC upgrade but I've noticed that my HE-500 have always lacked a certain 'engagement' factor. The HD650 are even worse regarding the 'engagement', but in a different way. This is most noticeable when I switch to the Phillips X2 that I got for my girlfriend for Christmas.
She runs iMac -> Schiit Modi 2 Uber -> Magni 1 (original - she' inherited' mine when I got the Polaris).
The X2 have issues, most notably some bass/midbass/mid bleed and grainy treble. But good lord do they make rock music sound amazing! The HE-500 are clearly better headphones with very fast transitions and no real bass/mid bleed. They just seem a tad thin.
Sadly, you don't offer an X2 module.
I'm tempted to buy a Kameleon with PSU and at least the HE-500 module, and maybe the black HD650 module. Is an X2 module a future possibility? I'd get the PSU standalone version because:
A: My girlfriend could use it if you ever make an X2 module. B: I can keep the Kameleon if I ever get a different, non-G1217 amp.
Thoughts? I'm most interested in hearing what sorts of changes there are to the HE-500. then changes to the black HD650, and finally the prospects of an X2 module.
The HE500 will gain some clarity, some would say you move a few rows to the front in a concert hall. Bass will basically be the same level but because the clarity improves you could also say the bass/mids become slightly less 'warm'. The treble quality will improve as the peak (you hear as 'detail' in cymbals etc.) will be lowered where the frequencies around it that are boosted will compensate as they are more present. The effect will be very similar as those who have the HE560 and LCD2 as the filter basically is very similar.
It's not so much the screen colour (black or silver) what most believe is the culprit but more of a question how stiff the pads are. When you have new pads on them you need the 'silver' HD650 module. This only slightly changes the sound... you will notice more 'body' and rumble and it will be just slightly more 'clear'.
You can also clearly see though the back of the HD650 which one you have.
You can test how 'soft' the pads are by pulling them off the HD650 and ly them them on a table. Then put something on it which weighs approx 1kg and see how much the pads compress. Here (in the HD650 section) you can see the differences.
The X2 has more bass and is slightly less 'warm' sounding and has more upper treble than X1 so could try to extrapolate based on comparisons here and there (Tyll's as well as others) and compare the differences to what I measured in the X1 here..
use your EARS to enjoy MUSIC .... NOT as an analyzer