ZMF Earpads for HD6xx Series Headphones

Thanks Zach for the loaner tour! My impressions were with both my HD600's and HD650's, both stock. Obviously six pads across two headphones is a lot to grapple with in ten days (over the Thanksgiving holiday no less) but I think I did an okay job sampling all the variables.

HD600s
Solid Lambskin:
I hadn't used my HD 600s much as of late, as they were coming off as too anemic to listen to much other than nigh-bassless old jazz -- so I was most excited to try this pairing, thinking that solid lambskin would best compliment the 600s, Lo and behold... it's not the utterly magic pairing I hoped it'd be. It does heighten overall bass resonance and relax the overall sound profile, without pushing things too far into warmpoo territory, but it also doesn't necessarily accentuate HD600s strongest suits -- to my mind, its midforwardness. It kind of rounds off the personality of the 600s, in my opinion, to something that's maybe a little more consumer-typical, but also just a bit... boring?

Suede Perf:
This pairing was likely the closest to stock. I do think these have an overall better soundstage, things are a bit more holographic than the sometimes-painfully 2D stock pads, The key difference between these and stock is it seems to me the Suede Perf also somewhat boosts the high end and midbass just a bit, while also keeping the mids nice and sweet. Overall an improvement over the old stock pads...

Perf Lambskin:
But god damn does this pairing take the cake. I don't know what it is but the perf lambskin pads turn the HD600s into a different pair of headphones altogether. For one thing, bass all from sub-to-mid is tightened up and boosted very pleasurably. Mids not only maintain their punch and sweetness but it seems almost enhanced, while also reducing their tendency towards being shouty, and treble is somehow both smoothed a bit yet brought into better relief, which even gives the impression of increased resolution. It's overall creamier, smoother, livelier, more detailed and resolving and transparent, sweeter... it's pretty amazing. You bet your ass I've already bought a pair of these.

HD650s
Solid Lambskin:
While I expected this to be a trainwreck of a pairing since the 650s are already a bit warm-leaning, that wasn't really the case. The ZMF pads in general seem to provide a bit more treble presence and that was felt here, as well, and while there is more bass it seemed to be localized mostly in the bloomy resonant subbass regions, as opposed to much of a midbass boost. I still don't particularly like this pairing as it resulted in something of a chamber effect, and the extra bass resonance didn't add much to the listening experience to my ears.

Suede Perf:
This is my favorite pairing with the 650s. It takes the overall profile of the 650s and adds a surprising amount more definition up top and turns the 650s into an actually really revealing pair of headphones, without any sensation of brightness or sibilance. (The 650s are deceptively revealing anyway, in my opinion, but this pushes that trait up into the highs also, as opposed to how stock, that only really applies in the mids.) I may actually get a pair of these for my 650s when their stock pads are dead, though I don't feel any rush to do so the way I did with the perf lambskin/600 combo.

Perf Lambskin:
To my ear, for some reason, this was actually closest to the stock sound of the 650s, while maintaining the trend of more top-end energy. For some reason that extra energy seemed more prevalent with the suede perfs... I think the perf lambskin keeps things a bit warmer, whereas the suede perf kind of brightens up the overall soundscape a bit, which nicely compliments their intrinsic wooliness.

Overall notes: I find these are a step up over stock in terms of comfort. The chamber provides more room for the ear, which means for me going from a bit of pressure on the upper helix of my ear to none at all. And ZMF's materials are, as ever, very comfortable on the skin for long stretches, and feel very robust and durable -- much more so than the stock Sennheiser pads.

I also came to find that I overall preferred wearing the pads backwards. When I initially installed the first pair I figured it'd be like other ZMF pads, with the seam on front, but with these the seam is supposed to go towards the back. The thick part being up front seemed odd, so I verified the seam was actually the 'back' of the pads and reversed them -- however for some reason I missed having the thicker portion of the pads towards the front of the Sennys. It seems the backwards-installation provides an uptick in comfort, and what I perceived to be an expanded sense of soundstage, and an ever-so-slight relaxation of the sound overall. I played around quite a bit with both orientations and universally preferred the pads backwards.

 

Seeing as how I scored a deal on HD650s for $75 with nasty pads and recently demoted all my planars to oblivion in search of a marbled HD600, I figured I'd try these pads.

I'd largely agree with futbutts up top, except I ended up with the suede on the HD600 for the sweeter timbre at the expense of that bass fill (custom cans mod incoming). And I really love the HD650 with the perforated lambskin. HD600 for work during the day, HD650 for gaming and lay down nights. I can't understate how fun the 650 are now, whereas I hated the 6XX for years, but putting the 600s on is like having a clear cup of water lol

For an all in-one type headphone, the HD600 with perf lambskin is the move. It ever so slightly stretches the ambiance of the room. My issue with it was it changed the mids a bit too far into feeling sunken, affected timbre slightly on live stuff mainly. But it also made the shrieky snap of the 600 a lot more noticeable.
Whereas I find the HD650 with suede a little too sleepy still, very stock sounding, but improved everything. The lambskin just made that sleepy sound a lot more dynamic with the added midbass fill, but that shriekyness that the 600 didn't need, really elevated the resolution these 650s have. They're maybe not as smooth, as the suedes, but smooth and visceral enough to be enjoyable. I just can't use them for work, I notice the slight coloration. Some of this is easy to tell listening to Helena Deland on Apple music, but also live stuff.

For big eared people like me, fear not, no driver is being touched. Even brand new 600 pads just barely glazed the driver. Comfort A+ on the suede, A on the lambskin, Build quality B- they don't seem to enjoy much roll swapping with the frequent bracket stretching. I'm done swapping until they wear out.

 

I've been listening to my 600s and 650s with the ZMF pads for about a year now. I had been listening with the Perf Suede on the 600s and the Perf Lamb on the 650s, but I just switched them around. The Perf Lamb on the 600s are really excellent. My daily drivers are 800Ss with the ZMF lamb pads on them. The Perf Lamb on the 600s had renewed my interest in them. Thanks, @futbutts , this is a nice tweak.

 

Pardon the bother, but I'm curious to hear how close those Perf Lambskins get to stock-but-very-worn-out pads tonality on the HD600, if anyone's able to make a direct comparison? I'm unsure from reading the impressions here exactly how pancaked the stock pads in the comparisons are, haha.

The pads I'm running with are maybe seven or eight years old at the moment and they're starting disintegrate in earnest (scary pics of their current condition here). Still usable but... yeah they're none too nice to look at, and more annoyingly my ears keep snagging where the outer velour's pulled away from the inner foam, which is now very much exposed, whenever I take the headphones off.

Mostly I'm hoping that the more restrictive pads might emulate the proximity effect you get with very broken-in pads (the voicing of the HD600 with new pads is decidedly not to my liking). Not particularly interested in improving bass extension cuz the quality isn't necessarily up to snuff, but hey I'll take it if it also keeps the more sedate upper midrange and smoother treble response.

 

I picked up a pair of the perforated suede pads for my 6XX. Not sure why I put this off for so long, but I'm genuinely impressed. I've never been big on the 6XX and mainly kept it around as a reference for comparisons. Honestly, I've spent more time with the 58X and enjoyed it more overall. The ZMF pads on the 6XX have actually put it back into the rotation for me. It's brighter - maybe "crisper" is a better word - but in a way that actually plays really nicely with the MMB2 + Piety stack instead of bringing out the harshness that this combo can exhibit. It also rectifies about 90% of the dreaded three-blob effect of the 6XX. It finally feels like a headphone with character instead of The Most Headphone Headphone that Ever Headphoned. Recordings that have a good sense of space (think ECM chamber music acoustics) work really nicely with it.

The pads _are_ a bit smaller and if they were any more constrained they wouldn't work for my ears. But they aren't more constrained, they do work, and I'm a fan. I haven't tried them on the 58X yet but I'll give that a try at some point. I suspect they won't fit that headphone quite as well and the lambskin options might be better. I've deliberately avoided reading most of the loaner impressions here so others may have tried that combo already, but I'd prefer to go in cold and then see how my impressions stack up.

 

For me on 2017 HD 6XX with Custom Cans mod (using 'bored' foam), perf suede > perf lambskin.

Out of WHAMMY via Soekris dac1321 with 4x upsampling from PlayPcmWin, the perf lamb give a roughness to the upper mids. The suedes seem to smooth this over, and also seem better balanced tonally from mids into treble, the latter being more elevated than with the lambs. The roughness with the lambs is also there from MCTH, less noticeable from Vali 2.

The slightly more subdued bass from the suedes vs the lambs is fine too, given the slight elevation and extension, and reduced distortion, of the bored-foam version of the mod vs stock there.

Concur with previous comments on improved lateral staging/imaging with both these pads vs stock.

Perf suedes will stay on.

 

There seems to be a consensus that vs the stock pads, either/both of the ZMF perforated pads seem to tighten up the HD 6-- bass. What follows is probably an over-interpretation of scruffy measurements, but at face value, it's interesting...

First, here's frequency response of my HD6XX (which have the Custom Cans mod with the bored foam insert) with stock, perf lamb, and perf suede pads, measured on a flat-plate coupler with no compensation. SPLs for the ZMF pad measurements were set at 90 dB @ 1 kHz; for the stock pad measurement, SPL was dropped a few dB so that it was similar to the ZMFs through the mid-bass (you'll see why after):

Edit: perf suede is orange, not blue!



Relatively, these particular stock pads (not too worn) give more bass and about the same level of upper mids thru treble as the ZMF perf suedes - which themselves give slightly less bass and more treble than the ZMF perf lambs (I trust neither my measurements nor my old ears beyond ~12k).

On its own the Custom Cans mod improves the bass tactility of the Senns, possibly because - with the bored & lighter foam inserts, at least - 3rd harmonic distortion is reduced relative to 2nd. In my distortion measurements with the different pads, I don't see any significant differences through the big ambient noise spikes I always get, but the picture is different when looking at spectrograms. Stock pads first, then lambs, then suedes:







Below ~300 Hz, decay time (Y-axis) is significantly longer in the stock-pad measurement. (If you're wondering why the X-axis doesn't go below 100 Hz, it's because there's a tradeoff between the time window and the frequency resolution of the measurement, and what the windowing algorithm does to the result, so whatever combination is chosen, results become the less reliable the lower the frequency).

My speculation on seeing this result is that vs the stock pads, the ZMF perforated pads reduce resonance or reverberation at bass frequencies, and this might be the reason for the perceived bass 'tightening'. But please note the disclaimer in the first paragraph

 

Don't mean to necro a thread, but I received the suede pads last week for my HD650s and have some thoughts.

Comfort/Build

• Comfort is good. I would say clamp force is slightly increased vs. my relatively new stock pads. I feel my right ear touching the inside of the cup more than with stock, but it's not bad. I don't like the way material feels on my head as much as stock, but then again I've always been a big velour fan.
• Installation was as easy as stock. I like how the attachment rings can be detached from the pads themselves.
• Material and build feels good. You could tell me these were stock pads from a big manufacturer and I'd believe you, but I guess that should be expected from Zach.

Sound

• The overall sound is noticeably darker than stock. There is a distinct loss of energy in the ear gain region and into the rest of the treble. Given that the HD650 isn't a particularly bright headphone to begin with, this results in a noticeable decrease in detail, especially for music that relies on a lot of distortion or guitars, like heavy metal.
• Soundstage is definitely improved vs. stock. DMS's description of it as being "five blob" is probably accurate. Width is especially more pronounced. These have a noticeable "hifiman dip" around 2k that helps with this, though even after EQing it out there is still an overall improvement in the presentation, so it's not the only thing causing the change. The fundamental design of the pad is probably doing some work.
• Vocals feel more distant and have less body than stock. EQing out the aforementioned dip helps with this significantly.
• Vocals can also sound a bit boxy. EQing around 500hz can alleviate this.
• Bass feels tighter. I usually EQ the mid bass down a bit around 140hz, but it's not as needed here.

After looking at different measurements, I noticed that none of them seemed to completely reflect what I actually hear. Someone over at ASR of all places actually pointed out that Capra had measured the pads along with stock ones, and it really reflects what I hear:



Don't worry too much about absolute values here, or compare them to other rigs. Focus on the delta from his stock measurement to the suede. This is how I hear these pads, though I think the peak at 5k isn't as bad as it looks. I have a feeling that my sense of the bass being tighter may be down to the decrease in sub bass shown here, but of course that could be run-to-run variance.

Overall, I can recommend the pads, but with the caveat that they need to be EQ'd to more closely match the stock pads' tonality if you don't like the darker tuning they provide. The improvement in soundstage is impressive, but I'd love to see Zach revise these a bit to try and claw back some of the tonality changes.

 

Do note that the brighter tuning of stock pads go away as they become compressed pretty damn quickly. Meanwhile I've had my lambskin perfs for a couple years now that have not. Otherwise ditto on the soundstage improvements: spacing the driver out and angling them a bit more does a lot

 

Oh yeah for sure. If you EQ the ZMF pads back to stock, you'll get to experience that sound for a lot longer than with the stock pads.

 

Or if you want to be a purist and make it brighter through physics (and more open sounding as well), get HD600s. I can vouch for the HD600+ZMF lambskin perf combo

 

Only counts as being a purist if it's the marble version.