[sennsay]

Yes it's a measurement flaw. And no, it's not a measurement flaw.
You sure are having fun tinkering with equipment. I've done a lot that too with my stereo.

I'm pretty new to headphones but this is what I understand so far:

Putting a driver in a small enclosed space over your ear will create an acoustic coupling to your ear canal.
Everybody has different ear canal and outer ear so no measurement rig will measure exactly what you hear. The MiniDSP EARS are made of silicone with a straight tube ear canal. Your ears are not. A professional rig will resemble a human are much better. You will hear small suckout around 10k or so with most headphones and a peak somewhere else in the treble (for me around 6k). Then there is the Fletcher-Munson curve... An equal loudness sine sweep (through loudspeakers) will sound like this to us (yes I inverted the graph on purpose otherwise will represent our ear's sensitivity)
See a dip around 10k?

Anyway watch this video:
Notice the measurements he shows in the first 30 second all have a dip around 10k.
You need to "see through" the peaks and dips in the HF and know which target response you like.
I like flat below 1k and Harman above that. So that is what my graphs use.
It may in effect be better to show raw measurements so you can see if the response is close to your preferred target.
Here's a raw measurement of my 540RefII's final tuning with my target response curve:

Well, I've been 'tinkering' for 50 years Rebuilding, restoring, building kits, setting up Linn Sondeks (back in the day, I owned two of them and set up others) plus many other turntables up until only a couple of years ago, anything from some valve (tube) gear to vintage amps and the occasional CD player. I love it all.
It's pretty much back to basics now, no room for a workshop at this current place where I'm recovering from a health crisis, so simplicity it is for me here (with my partner). Headphones only now, whether it's with the Magni 3+/Frankie combo, the Schiit multibit DAC or with the small but excellent Corda 2Move portable amp (with or without it's built in DAC) which I can use very occasionally with the Sony WM-D3 Pro Walkman, which was fully refurbished a couple of years back. The No 1 HD540 Ref1s have been with me as a constant for 34 years now, even when packed in their box for short periods while I moved around. The only extra tinkering I've done more recently was pull a Yamaha K-220 cassette deck out of the local tip's electronics dumpster. It had no lid, a few small knobs missing and needed new belts. I cleaned it up, replaced the belts, lubed it and it runs perfectly! Stable (it has two motors) and excellent sound quality even for a modest deck .. in fact I've heard much worse from more expensive decks. I run it every now and then to keep the lube moving and the belts supple.
I hear you about the top end of your graphs, I get it Thank you.
I have discovered that the original steel cable knocked a couple of dB off the signal strength though, I have to turn the amp up a couple of notches to get the same or similar level when using the Mogami cable. Extra resistance? I haven't measured them, I just raise or lower the volume to compensate.

 

[BEYER]

Yes! I have the felt tuning rings. They came with my set when I received them and I have them installed in my pair at all times.



My OEM hybrid pads (the white faced pads) are still like-new. They were likely stored in a climate controlled environment and had next to zero use, judging by the color of the fabric still being white and not faded. Like I said, the foam is still like-new, so I am not inclined to rip the pads open to replace it. I don’t use these pads though as I’ve found them to be detrimental to the sound in many ways. My two favorite pads for the 540 Reference and Reference Gold headphones are easily the OEM velour pads, and the Wang pleather pads. I use the Wang pads on my 600 ohm 540 Reference all the time. I keep the OEM velours on my 540 Gold.

Hi can you tell me the thickness of both felt discs and inner diameter of the second disc ? Thanks

 

[nexgen]

I would like to share with my current best earpads config on my HD540 Ref II. I have tested about 10 differents sets of earpads from pleather , velour, gybrid to real leather. The best result I got from pleather 105mm earpads purchased here :
https://www.aliexpress.com/item/1005004771283958.html

Clear, detailed, lively, biggest soundstage with good tonality balance from bass to highs. Felt rings brings more tightened, squeezed, less airy sound so I removed them in that combination. I must admit I use silver plated balanced cable to Gustard A20h DAC/AMP. Sound is very open, smooth without harshness still with heavy but not bloated to mids bass. IMHO much better HP than HD600 or HD650 which I also have at home and did comparisions between them. HD540 Ref II are my one of fav open Sennheisers all time and one of most beloved dynamic HP just after HD560 Ovations which are a bit more refined

 

[sennsay]

I would like to share with my current best earpads config on my HD540 Ref II. I have tested about 10 differents sets of earpads from pleather , velour, gybrid to real leather. The best result I got from pleather 105mm earpads purchased here :
https://www.aliexpress.com/item/1005004771283958.html

Clear, detailed, lively, biggest soundstage with good tonality balance from bass to highs. Felt rings brings more tightened, squeezed, less airy sound so I removed them in that combination. I must admit I use silver plated balanced cable to Gustard A20h DAC/AMP. Sound is very open, smooth without harshness still with heavy but not bloated to mids bass. IMHO much better HP than HD600 or HD650 which I also have at home and did comparisions between them. HD540 Ref II are my one of fav open Sennheisers all time and one of most beloved dynamic HP just after HD560 Ovations which are a bit more refined

Well done and thanks for that. Personally, I would like to know what the other pads in your comparison actually were. Did you use wang_yifei pleathers, f'instance? I use similar pads to your chosen set on a pair of HD430s and although they're good, they do squash image height a bit, as I am used to height, depth and space on the HD540 Ref1s. Not that I am making a comparison here with your chosen set, just that they are of a similar construction. Cheers.

 

[sennsay]

Well, I visited AliExpress and bought a single set of the 105mm pleather pads as described above. At the 'introductory' offer of just 77c per pair and you are only allowed to buy one set. Hmm. I would have bought several pairs but that option is out. Now I have to wait 11 days for them to be even shipped, let alone the loooong wait until apparently November some time for them to arrive. I'd rather have paid more for a faster service, but even the speedier post wasn't an option either. Ah well, hopefully I haven't moved home by then! Whether they will work well with the HD540s remains to be seen, as my No1 Ref 1s do not have the upper mid/lower treble peak of the HD540 IIs, and are very smooth through the mids and top end with the Mogami cable.

 

[nexgen]

Well done and thanks for that. Personally, I would like to know what the other pads in your comparison actually were. Did you use wang_yifei pleathers, f'instance? I use similar pads to your chosen set on a pair of HD430s and although they're good, they do squash image height a bit, as I am used to height, depth and space on the HD540 Ref1s. Not that I am making a comparison here with your chosen set, just that they are of a similar construction. Cheers.

Thanks. IMHO they have best soundstage size in all dimensions from these what I have. Other sets of earpads I have grouped as pairs but in one big bad and I do not describe where I got them. Some have arrived with purchased headphones from second hand so hard to identify. Sorry. From wang_yifei if I good remember I got only real leather earpads for HiFiMAN Edition Xv2 and they were very good but not better then much cheaper from Aliexpress when I bought for Edition Xv1.

Well, I visited AliExpress and bought a single set of the 105mm pleather pads as described above. At the 'introductory' offer of just 77c per pair and you are only allowed to buy one set. Hmm. I would have bought several pairs but that option is out. Now I have to wait 11 days for them to be even shipped, let alone the loooong wait until apparently November some time for them to arrive. I'd rather have paid more for a faster service, but even the speedier post wasn't an option either. Ah well, hopefully I haven't moved home by then! Whether they will work well with the HD540s remains to be seen, as my No1 Ref 1s do not have the upper mid/lower treble peak of the HD540 IIs, and are very smooth through the mids and top end with the Mogami cable.

Ohh that is propably because of destination. I can buy more than 1 pcs and for 1 there is faster shipping option (about two weeks to delivery) for additional 0,53USD.

 

[IgorUA]

Thanks for the link! Bought 100mm for £0.59. Do you think they will be the same?

 

[arnobartels]

Bought some too. They look cool. If they arrive I'll post some measurements.

In the mean time my best pads are still the HD250 Velours ( https://www.ebay.com/itm/254669296151 ) with some damping for the highs. I now use a double ply of toilet paper instead of the cotton disk I posted before.

The cotton attenuates the deep bass too much. With the cotton I needed to EQ the bass. With the 2 ply toilet paper I can live without EQ. There's a bit of a peak at 6k that I can't get rid of but so far I don't feel I need to correct for that with EQ.



Toilet Paper:

Cotton disk:

 

[sennsay]

That 6kHz peak is the natural response of the HD540IIs, as part of the natural tuning. It can only become 'eased' though not eliminated with the Mogami cable (and no doubt some others) that I used when I had a set for a while, as previously mentioned, and the changing of cloth or paper filters as you are doing. The stock steel cable highlights the peak as far as listening goes and that in itself is not necessarily a 'bad' thing, as I use the stock cable more often than not with my No 2 HD540 Ref1s, despite the midrange grain that comes with it. Some music just comes alive a little more, depending on the output modules I have in the FrankenDAC. It reminds me of the sheer joy I had for so many years with my stock HD540 Ref1s where nothing else (HD650s included) could come close to them.

 

[arnobartels]

I use the stock cable with my Ref II but it turns out it's not steel. It's copper as indicated on the box:

 

[arnobartels]

I would love to use angled pads with these phones to enhance the staging. Can't find any in velour though. Something in sheep's skin would be the ultimate luxury version for me but I'm afraid it will not sound as good as velour.

Anybody know of some angled pads that will fit?

 

[sennsay]

Yes, I understand that, it's more to do with the braiding around the copper, a term just used by some of us old hands to describe the original stock cable. It's still peaky and grainy.

 

[sennsay]

I use the stock cable with my Ref II but it turns out it's not steel. It's copper as indicated on the box:

See reply above.

 

[arnobartels]

Of course with some sheepskin angled pads a luxury cable is a must. And a nice wooden box to finish it off...

The 6k peak does actually almost disappear with the cotton damping rings. The 2-ply toilet paper gradually rolls off the higher frequencies from 200Hz upwards producing a down sloping frequency response with a more pronounced 6k peak and a less smooth treble. The bass roll-off actually stays the same. The 2-ply toilet paper sounds warmer with good bass. Good if you don't want to use EQ.

The cotton rings sound (and measure) more neutral. The mid and highs are flat now so the bass is relatively a bit softer. However with a little EQ of +3.5 dB at 35Hz with a Q of 1.0 the bass is even deeper than with the toilet paper and the mids and highs are near perfect. Actually as good, if not better, than the HD600.

Here's the HD 540 RefII with HD250 velour pads and cotton rings measured (without EQ!!!) on my MiniDSP (bottom traces) and the HD600 as measured by Crinacle (top traces). I derived my correction for the MiniDSP from measurements with other MiniDSP units found on the internet, so give or take some unit to unit variation in the MiniDSP and error in my correction, my guess is the drivers of the HD540 and HD600 are nearly identical.

And here I added 3.5dB at 35Hz with Q=1:

Needless to say this actually sounds shockingly good!

Cotton make-up removal disk (big ones) with well compressed outer layer work best:

Cut to size (diameter 52mm, hole size 16mm):

 

[BEYER]

@arnobartels
How do you hold those cotton discs in place?