InnerFidelity April 2014 Update

Headphone Measurements
As usual I've updated the AllGraphs.pdf of course, and added the cans to the measurement datasheets page. I've also linked to the measurement sheets in the headphone name preceding the paragraphs below. New additions include:

  • Second AKG K812 - A bit of old news as it's mentioned in the AKG K812 review, but I've updated the allgraphs.pdf and measurement page with the second set of measurements for this headphone. Measurements were consistent with the previously measured K812.
  • Revised Shure SE846 - One of the Shure engineers emailed me with concerns that the filters were improperly installed for one of the measurements. I did find this to be the case and remeasured the SE846 with white filters, blue filters, and black filters. I found them a bit hard sounding for my taste.
  • Polk Buckle and Hinge - Albeit a bit old school, both these headphones are pretty good looking and comfortable. The sound on both was fairly even, but overly warm and slow unfortunately.
  • Sennheiser HD8 DJ, HD7 DJ, and HD6 DJ - These were a bit of a head-scratcher. They're far from neutral, but they might be a good match for working DJs. The bass is powerful and tight, and the treble is very non-fatiguing due to a big notch out of a region centered at 6kHz. Sennheiser claims these cans were voice by working pro DJs. My problem is that I'm not a DJ so I really don't know how to evaluate this EQ for the intended use; I can say, however, that they aren't neutral enough for audiophile listeners to use for listening pleasure. I'll also note that the HD6 DJ is supposedly designed for studio use while mixing, but with a frequency response not that dissimilar to the HD8 DJ and HD7 DJ I have to question if it's really a good headphone for that application.


    The above plot compares the three headphone's compensated frequency response. While there are some differences, the overall character is quite similar for all three cans, and quite far from neutral. Sorry, don't think I can review these cans in the context of DJs, and don't think they're worth reviewing for audiophiles.

  • Philips TX1 and TX2 - I don't think these are available in the U.S. yet. Both models are low cost (well under $100 is my understanding) dynamic driver IEMs, and both measure quite well. I'll be shipping them off to ljokerl shortly for his consideration, but after a quick listen I was quite impress with these.
  • Audio Technica ATH-AD2000X and ATH-A1000X - I must admit that mounting Audio Technica headphones with the "winged" headband pads is quite a challenge. These headphones—and others in the AT line with this type of headband—do not have a earcup mechanism to tilt the earpads up and down. Coupled with the fact that my Head Acoustics measurement head is a little smaller than a normal male head, and I find myself really struggling to get a good measurement. I think I did accomplish it, and measurements (especially the uncompensated FR plots) look pretty stable. I'm left with the feeling, however, that AT should take a fresh look at this headband design and do a little update to help them fit more reliably. I found both a little to thin and tizzy sounding.
  • Audio Technica ATH-M50x - Yes! Here's a perfect example of taking a good headphone, giving it a little love, and re-issuing the model with some nice sonic improvements. Overall FR has been given a slightly warm tilt, and a good bit of the stridence (the one serious problem with the M50) has been reduced. This is a good headphone made even better in this refresh...yupper, it'll be reviewed soon.
  • Phiaton Chord MS530 - Well waddaya know, I think I like this headphone. The Chord MS530 is an on-ear, Bluetooth headset with noise canceling, that will also run passively on the wire. I've only measured it passively so far, and due to the design of the flat pads and the stiffer than normal ears on my measurement head I had quite a difficult time. They're a little mid-fi sounding—uneven and just a tad hard—but the overall balance and listening experience is pretty good. The reason I like them is mostly about how convenient they are, and how quickly they pair up with other devices. The supra-aural style may not lend itself to long-wearing comfort, but it does make them quite easy to don and doff. Just a solid general-purpose headset for every day use, it seems to me. Review sometime soon.
  • SOL Republic Master Tracks XC - Having been disappointed with previous SOL Republic headphones I didn't hold out much hope for these new cans. Lo and behold, I think they're quite a bit better than previous offerings by SOL. Response up to 2kHz is pretty darned good...unfortunately above that thing start going down hill. There's a significant notch at 5.5kHz, and the mid- and upper-treble are about 5dB too rolled-off. Very happy to see SOL moving in this direction and hope they keep working on it. Not good enough for a review though.
  • Additional headphones measured without comment - Skullcandy Crusher (review here); Fidue A63 and A81; Westone W10 and W40; Dunu DN900; and Meze 11 Deco

Upcoming Reviews
Been working on a review of the Audeze LCD-X, a headphone I like and will review, but I've learned of some interesting changes to both the LCD-2 and LCD-3 and need to remeasure the most current versions before finishing and posting up the review. As mentioned above the Shure SRH1540, Audio Technica ATH-M50x, and Phiaton Chord MS530 are all in the works. Additionally I've got one of the new Bottlehead Crackheadphone kits in house and have measured the Monoprice 8323 prior to modification. Really looking forward to doing another kit from Doc B.

In an effort to get familiar with some of the more expensive streaming speakers out there, I've managed to wrangle up the Bluesound Pulse (and a few other Bluesound products); Cambridge Audio Minx Air 200, and Philips Fidelio Sound Spheres. The Sound Sphere's are amazing for the price...they'll get a review at some point. Michael Lavorgna over at Audiostream has done in-depth reviews of the Bluesound stuff (Vault, Node, Power Node and Duo) and I found myself in agreement with his observations so I'm not sure if I'll be doing a full review. My motive for getting the loaner gear was to get some experience with full-home streaming systems and to begin to get a feel for how "personal audio" products fit into that paradigm. I'm sure I'll post up some comments relative to that at some point. The Cambridge Minx was okay—good bass, but a little lacking in the top octave—but its BMR (balanced mode radiator) drivers did indeed provide wide dispersion of high frequencies delivering quite good speech intelligibility off-axis. Probably not going to review it due to treble response slightly lacking.

T.H.E. Show Newport
If you live in Southern California, you might be interested in checking out T.H.E. Show Newport May 30-June 1. I'll be attending and holding one of the panel discussions. Very much looking forward to seeing all my SoCal headphone friends. Hope to see you there.

Hope you're enjoying the beginning of spring...still snowing at night here in Montana. Argh. C'mon spring!

ashutoshp's picture

Measurements please. I am waiting with my salivary glands in overdrive.

Tyll Hertsens's picture

I have contacted Val and the new cans are on the way.

mikeaj's picture

I guess they weren't kidding about well under $100. I'm seeing sellers on eBay (new) for ~$30 and ~$40 respectively. Similar kind of tuning as the Fidelio S1 and S2 it seems, but with even more bass (probably too far, but eh).

Just because this page is traditionally a place for bugging Tyll with requests (never catch a break, huh? good luck), any plans to get in the new crop of planar magnetics? This month or relatively soon, Oppo PM-1 should be available, and same for HiFiMAN's refresh of HE-400i and HE-560.

Tyll Hertsens's picture

I'm used to it. The Oppos are in shipment, and I'm sure I'll have no problem getting the new HiFiMAN cans. I too am very excited to here this new generation of planar magnetics.

PierPaoloG's picture

Hi Tyll,


this is Pier Paolo from Rome, Italy.


I have a HiFiMAN HE-6 very well driven by a self made headphones amplifier. (better than any othe ampli I have ever heard, included loudspeakers ones, in driving the HE-6 and the orthos in general.)


Now, I would buy also an AUDEZE to enjoy that liquid experience. I have heard, in my system, the LCD-3 and I have loved it. I have heard the LCD-X in a different setup and I have liked it also a lot.

So, because I can't compare them side by side I need someone to help me in choosing the right one. I think that the X is more linear and detailed, more transparent and also les coloured in the midrandge, when compared to the X, but the X has less Bass extension, and I love 3's bass.


I think that you are testing the X and I know you love the 3, so: can you help me?


Thank You

wnmnkh's picture

Is Oppo PM-1 coming to your way? cool

BaTou069's picture

Hello Tyll,


you measured the Shure SE846 with the different filters, but all you say about them is I that you "found them a bit hard sounding for my taste"

What do you mean by this? Maybe you could upload a review :)



maciux's picture

Hi Tyll


It's odd and interesting, because according to Audio-Technica's descriptions the x-series headphones are the same sonically as predecessors. I'm wainting for review. Have you heard ATH-M40x? My favorite from x-series, also a little warm and bass accentuated, but flatter and lighter sounding than M50x.

wongwarren's picture

I own the M50 and have heard the M50x. I wouldn't say they're the same sonically. There's a very slight bass boost according to my brief experience with them at the headphone store.

ashutoshp's picture

I agree with wongwarren and Tyll that there are differences, which is not surprising as Audio-Technica seems to have changed the structure/composition of the foam on the ear cup as well as the ear-cup itself. Tyll's measurements also indicate better responses overall from the M50x and who knows, they may have made changes to the drivers as well but why rock the boat. 

Look at SonicSenseProAudio's youtube channel ( They have a relative audio comparison of the ATH-M50 vs M50x. I suggest streaming at 1080p and if applicable, flatten any equalizer on your gear. There is indeed a subtle difference. Disclaimer: while they will sound different on youtube than your 'phone, remember its a relative and not an absolute comparison.   


maciux's picture

Ok, thx. Good to know :) Haven't heard previous version, so I'm waiting for Innerfidelity review.

wongwarren's picture

In any case, I can't wait to see what Tyll has to say about the refresh and if it will displace the original's spot on the Wall. Might consider if Tyll thinks it's worthy of the Wall even though I have the original.

imackler's picture

Cannot wait, Tyll, for the review. I fear it will be too bassy for me, but there is so much that seems so right about them. 

Jazz Casual's picture

Hi Tyll, I don't recall you commenting upon the TH900 when you posted the measurements but I'd appreciate your thoughts. If they are overwhelmingly negative and you are reluctant to post them publicly, please feel free to PM me. Thanks. 

Lumos's picture

Heya Tyll

I would like to ask if you planning to rewiew AKG K612 and K712? Some people suggest that K712 is poor man's HD800 do you agree? 

Also interested in K612, which seems to solve some of a problems its predecessor was suffering.

I will greatly appreciate your opinion


Three Toes of Fury's picture

Too weird....i recently snagged a pair of Sol Republic Master Tracks Studio XC and really like them.    I jumped onto innerfidelity and found only a review of the on-ear tracks.   I was planning on letting you know that the Master Tracks (over ear) might be worth a listen...turns out you were already ahead of me...nice!  

Also your data (which i need to get better at reading and interpreting!)  may explain a weird phenomenon with these cans...alot of songs sound pretty great but every so often i come across one that sounds flat...maybe it ties in with the mid/upper trebble roll off you mention?

Thanks dude...keep the great reviews, data, and headphone/amp knowledge flowing!

Peace .n. Living in Stereo,




ultrabike's picture

Very interested in how they perform in general (proly Tyll usual review rig), and how they pair specifically w the Bottlehead Crack.

Crackheadphone Kit Linky

Hekeli's picture

So what's your take on HD8 vs M-100? That's a comparo that looks very suitable.

Several people have preferred HD8. Sadly I haven't heard M-100 myself, but HD8 is one of the best "basshead delight" cans I've heard yet. Zero fatiguing highs, isolation looks better than M-100, even the bass boost starts lower (<200hz) than M-100 which was your complaint.

Nice to see my measurements were pretty spot on.

Mintroo's picture


As an owner of the SE535 based partially on your recommendation and now an owner of the SE846 I am surprised you did not like them. The 846 to me cures the treble roll off of the 535 and adds an incredible bass response.  My I ask what filer did you use when listening?

JRAudio's picture

Same with me. I have had the SE535. Even it was good, I still needed to EQ in Bass and Treble a bit, to fit my taste. But now with SE846. I have had fear, that the bass would be too strong, but this I can adjust very easily with the seal of the ear tip and with the treble, I installed the "brighter" on, and after "break in" in 2 days, I am very happy with this IEM. The isolation is great, and I enjoy the sound every week, when I am sitting in a train to travel 2 x 1.5 hour every week, or when I sit in air plain. This is the best (non custom) IEM that I ever had. I am totally satiesfied and would / can recommend it to every friend who is asking me for a good IEM. As a side node, I use it with my iPhone 5. I do not want to carry any second device with me when causal traveling, but when I sit down in the train, I really like to listen to music with the IEM and it is really a pleasure for me to do this.


DrForBin's picture


really sad to learn that these are so not neutral, i had high hopes for a flat studio monitor at this price point.

i, too, would like your take on the K712's.


wongwarren's picture

Wrong post.