Brainwavz M1:  Mid-fi Saving Grace
 

 

 
 
SPECS:
http://www.yourbrainwavz.com/m1.html
 
WHERE TO BUY / COST:
 
http://www.mp4nation.net/brainwavz-m1-iem-earphones
$44.50 new
 
TEST TRACKS
 
California Girls by The Beach Boys found on Sounds of Summer - The Very Best of The Beach Boys – Track used to test the entire spectrum from bass, mids, to treble.
 
Propeller Seeds by Imogen Heap ( Instrumental ) – Track used to test soundstage and overall presentation of soundstage
 
River Flows in You by Yiruma ( Piano ) – Track utilized to see if the headphone / IEM represents piano in a realistic manor
 
Vivaldi Guitar and Lute found in the The Spanish Guitar Music Colección – Track used to hear the metallic sound of strings, echo of environment, and sound signature of the lute and Spanish guitar.
 
OVERVIEW
I have been listening to Brainwavz products for many years and find the M1 and M2 wonderful entry-level IEM’s.  The M1 in particular is especially outstanding both in sound quality and fit.  It is aesthetically pleasing, easy to insert, and provides a fun sounding signature bound to suit the needs of many listeners.
 
AESTHETICS
The M1 and M2 fit similarly, but the M1 has a smaller body which makes it easier to insert and hides the bulk of the IEM inside the ear.  Brainwavz continues their trend of supplying myriad tips including some Comply foam tips with the accessories.  Unlike the M2 the M1 comes with a plastic cable clip to help remove any microphonics found in the cable.  Each earpiece is clearly labeled with an L for left and R for right, but they do lack any signs of extra strain relief like the M2.  The jack is terminated nicely and protrudes at an angle just over 90 degrees making it fit extremely well into a portable snugged into a protective case.
 
ACOUSTICS
Unamped: I tested the M1 using an iPod touch 5^th Gen as I use it as my primary travel music companion.  The M1 remains a wonderful IEM for on the go music musts.  They are bassy and fun without being obnoxiously so.  The typical upfront sound found in almost all of the Brainwavz products I have heard to date remains intact.  The treble is nicely rolled off to not bear down on treble sensitive listeners.  The M1 is just a super fun IEM to listen to and anything I tossed at it sounded great on an unamped portable.
Amped:  Amped the M1 became noticeably bassier and better controlled.  The signature can be easily dialed in and grooves nicely with funk, smooth jazz, and some moderately paced rock.  Some tracks become too boomy with the M1 heard in Vivaldi’s Guitar and Lute track listed above.  A quick turn down of the volume knob mellows the bass and the M1 instills another fantastic listen.
 
CONCLUSION
The M1 is a favorite of mine and perhaps my new low-cost mid-fi IEM.  The sound is just awesome for such a small single dynamic driver.  Bass lovers will not be disappointed, but the M1 is not boomy enough to scare away the more delicate listener.  The accessories are complete and very well thought out making the travel case and tip choices considerate critical listeners who remain on the go.  The cable is well made and although it lacks the sometimes excessive strain reliefs of the M2 it is still constructed of fine materials.  The M1 is very small which makes it ideal for smaller to medium sized ears.  Those who have larger ears may want to move up to the M2 due to possible fit issues, but larger Comply tips are available that should accommodate almost all listeners.  Back to my listening and I hope you all enjoy this collaborative hobby that is hi-fi!

Brainwavz HM5 Earpads
 

 

 
 
 
 
 
 
 
CHOICES
Velour
Pleather
 
COLORS
- Pleather pads come in Black, Dark Red, Red, Brown, White

- Velour pads available in Black and Red
 
Cost:  $8.50 USD each
 
Big thanks to Brainwavz for loaning a pair of both the pleather and velour pads for this review.
 
What headphones do they fit?
Brainwavz HM5
Shure SRH440
Audio Technica ATH-M50
 
OVERVIEW
If, like me, you started off years ago with a headphone like the ATH-M50 and after some serious use realized that the earpads are no longer in their ideal condition, then these HM5 replacement pads from Brainwavz are for you.  They fit beautifully onto the earcups of the ATH-M50 and with a little effort they fall into place.  Having a great fit is a must to achieve the same seal and comfort as the stock pads.  These replacements pads do just that!
 
AESTHETICS
The pads come in four colors: Black, Dark Red, Red ( seen here ), Brown, and White.  The colors are fantastic, the stitching is also very well done with no signs of quality control issues.  As seen in the pictures the pads are a bit larger than the stock ATH-M50 pads providing more ear room and a softer feel around the outer ear.  The HM5 pads are also thicker which will be a great change for those of you wanting more depth in the earpads.  For travel I recommend the pleather pads to provide a better seal and block out some of the noise.
 

 
 
The velour pads come in the black and red.  They also provide you with a little more comfort than the pleather pads by removing some of the heat build-up from around the ear.  The velour pads are an excellent choice for long listening sessions.
 
ACOUSTICS
 
The Pleather Pads
The thicker pads change the sonics slightly, but not enough to distract from the overall sound signature of the ATM-M50.  The bass is the obvious region of the spectrum affected.  It is slightly thinner and less punchy perhaps due to both the seal around the ear and the proximity of the driver to the ear.  A slight compression of the replacement pads while listening reveals that the bass can be enhanced with little effort.  This indicates that the acoustic seal is not the same as the original pads.  I found them more than adequate and suspect with a little age the bass will fall more in line with the original pads.
 
The Velour Pads
Many great headphones like the beyerdynamic DT 990, Sennheiser HD 650, and even the AKG K712 Pro utilize velour pads.  Velour typically provides an open seal around the ear which if coupled with an open driver resonator design provides a more airy presentation.  It allows the air to couple to the ear differently than a sealed / leather earpad.  You should expect more treble and less boom in the bass.  The HM5 velour pads follow this expectation perfectly.  These pads work wonders if you are sensitive to bass or pressure build up.
 
CONCLUSION
If you are looking for a colorful replacement pad for the HM5, ATH-M50(x), or even the SHR440 the HM5 replacement pads from Brainwavz are an excellent choice.  They are well made, very comfortable, and do not add any unforeseen acoustic problems.  The leather pads seal and provide more bass than their velour counterparts.  The velour pads are more comfortable for hot listening sessions or where more treble focus is desired.  Both remain a simple and inexpensive way to tune the listening experience.
 
LINKS
Brainwavz HM5 Replacement Pads
http://www.yourbrainwavz.com/HM5padsthick.html
 
SRH440 with HM5 pads
http://www.head-fi.org/t/741698/new-brainwavz-hm5-pads-different-colours-velour-leather
 

The 2014 Brainwavz S5:  A Single Dynamic Driver IEM
 

 
Specifications Found here:  
 
www.yourbrainwavz.com/s5.html
 

 
No measurements for the S5 were available at the time of this review.
 
Initial testing on an iPod touch ( 3rd Gen ) no EQ

 
The idea with the iPod is to ensure that the S5 is easily driven and controlled by a portable player.  The S5 having high sensitivity and low impedance is easily driven to very loud levels with a portable and the drivers were nicely controlled although the bass becomes boomy at times.  The S5 sound does improve with amping.  I also noticed that the S5 does sounds more laid back with a portable compared to my home rig.
 
Full review conducted on my home rig:
 
Sources:  PC playing 256kbps AAC or better files, Internal DVD player, iPod Touch 3rd Gen.
DAC:  Grace Design m903 ( 24 bit mode )
AMP:  HeadRoom BUDA in single ended mode
Interconnects:  Kimber PBJ RCA and Seismic Audio Balanced patch cables
 
TEST TRACKS
The Beach Boys:  Surfin’ USA
Chick Corea:  Three Ghouls, Part 1
Karsh Kale: Longing
Maroon 5:  Won’t Go Home Without You:
Michael Jacskon: Wanna Be Startin’ Somethin’
Patricia Barber:  Dansons la Gigue
They Might Be Giants:  Spiraling Shape
 
ACCESSORIES

 

 
 
FIRST IMPRESSIONS
I will compare the Brainwavz M2 and S5 throughout this review.
My history with Brainwavz goes back to the M1 and M2 days.  I am intimately involved with listening to the M2 as it remains my budget IEM of choice.  Glancing at the spec differences between the M2 and the S5 there are a few noteworthy tidbits.  First the frequency response is reported to be wider on the S5 going from 18 Hz – 25 kHz whereas the M2 spans 20 Hz – 20 kHz.  Typically when I see a manufacturer change the specs like this it points me to the fact they are purposely altering the spec because the sound is obviously different than their other models  The S5 holds true to this fact.  In bass sounds extended and the image becomes more up-front under amped conditions.  The impedance and sensitivity are lower, but the M5 reaches ear-blistering loudness on my portables so there are no worries with using either IEM.
 
You can fiddle around with impedance calculations here:
 
http://www.apexhifi.com/specs.html
 
Read more about impedance here:
 
http://www.head-fi.org/t/607282/headphone-amp-impedance-questions-find-the-answers-here
 
The different between the M2, my go to affordable IEM, is significant. 

The S5 is noticeably bassier which at times becomes too boomy and during other tracks is fun.  The S5 also contains a clearer midrange, and a slightly more up-front image.  The S5 improves upon all aspects of the sound signature of the M2 except the loose bass and hint of sibilance in the upper midrange.  I had no trouble sticking with the S5 during my listening sessions as the M2 sounded too mute and laid-back from my home rig after listening to the S5.

 
LET’S TEST THIS THING
 
Check Corea’s Three Ghouls, Part 1:  This track tests quickness, realism, and treble.  It also tests how up-front sounding a headphone can be.  The speed and glistening treble were well reflected with the S5.  The track sounds quick, fun, and responsive to the cacophony of the Three Goals.  The splash of the cymbals was not as true to form and metallic as from a high-end headphone like the AKG K712 Pro, but certainly was not diminished like so many other IEM’s in this price point.
 
Karsh Kale’s Longing is a track I use for general imaging and engagement.  As Tyll will tell you sometimes how a headphone makes you feel tells a lot about the headphone itself.  The image of the S5 collapses during this track detracting from the space and echo.  The general presentation remains intact, but the spacious gravity is almost completely lost as the image becomes too up-front.
 
Maroon 5’s Won’t Go Home Without You is a track I typically use to test crossover issues with speakers and IEMs.  It also gives rise to issues with male vocals and too up-front sounding headphones.  This track reveals some blurring occurring in the S5 as well as slight sibilance.  I found the S5 fatiguing both with my portables and amped rig with this track.
 
Michael Jacskon’s Wanna Be Startin’ Somethin’ is a track that tests the up-front nature of headphones.  It also tests treble and vocals as with some headphones like the AH-D2000 and K701 can be harsh.  The treble was surprising soft and laid-back with this track.  I finished the entire track without fatigue.  The upper midrange became a little tizzy at times having a slight buzz sound blending in with the abundance of instrumentation, but nothing that sounded too far out of place for an IEM in this price point.
 
Patricia Barber’s Dansons la Gigue is an excellent track to test separation, bass, and female vocals.  A headphone like the Grado RS-1i struggles here as things become too one dimensional.  The bass blurs into the mids and further into the treble.  The bass sounds awesome with the S5 proving lush and full.  The detail remains clear enough to resolve the full spectrum showing only slight diminution in the upper treble.
 
The Beach Boys’ Surfin’ USA is a track I use to test how even a headphone may sound.  Much like using Pink Noise it reveals any glaring issues like a lack of midrange smoothness, imaging, and even quickness.   The S5 reveals the nice echo and general flow of the track.  However, I did notice a slight sibilance in the upper midrange heard on the letter “S” and when the words “Inside outside USA” were voiced.
 
They Might Be Giant’s Spiraling Shape is a track I use to test male vocals in detail and how the kick drum resonates.  I also use it to reveal the metallic splash of the crash cymbal.  Here the laid-back nature of the S5 becomes obvious.  The track is soft and nice to listen to without any obvious weakness, but no part of the track is especially clear nor exceptionally presented.  The splash of the cymbals is not metallic and the kick drum is a single tone making the S5 sounds unnatural.
 
FORM, FIT, FUNCTIONALITY
The cable of the S5 is flat rather than a twisted pair and the headphones are supposed to be installed into the ear and then the cable routed over the top of the ear.  The problems for me began with the flat cable having too much surface area and pulling the IEM out of ears at time in the recommended orientation.
The IEM can be worn in the cable-down configuration quite comfortably, but they protrude will passed the outer ear which may get attract some unwanted attention.  There is a lack of left/right labeling on the body and how they fit inside the outer ear when installed with the cable up is the only way that I could find which earpiece goes in which ear.  Not a big deal in most instances because we typically just want to listen to music in a general sense while on the move, but for more critical listening a simple red “R” and blue “L” would suffice.
 
The case is well designed and filled with myriad tips.  The addition of some Comply foam tips is a nice touch.  I found the bi-flange tips to be the best sealing and sounding tips.  Brainwavz also provides a slick ¼ inch adapter which easily clicks on and off of the 1/8^th inch standard jack plug at the end of the IEM.

The angle of the resonator, the part of the headphone inserting into the outer ear, was only comfortable or adequate with two of the abundance of tips.  The Comply foam tips simply collapsed into my ear canal and completely blocked out any sound coming from the driver making them an impossible combination with the S5.  This is something that the M2 does not suffer from and Comply foam tips are a huge improvement for that IEM.  The accessories cover a wide variety of tips and sizes so finding one that fits should not be an issue, but optimization may be difficult or impossible for some.

 
CONCLUSION
The S5 improves upon the sound signature over the M2 especially in the bass and presentation.  The treble extension remains in check without becoming fatiguing, but is not as extended as most balanced armature driver IEMs.  My biggest complement to the S5 is the up-front image and midrange clarity which Brainwavz keeps improving upon.

A big thanks to Headphone.com for loaning me the AKG K712 Pro and HD650 for this review.
 
A hearty thanks to Tyll Hertsens from Innerfidelity.com for loaning me a pair of AKG Q701 also used in this review.
 
Specs:
http://www.akg.com/K712+PRO-827.html?pid=1408&techspecs
 
Frequency Response Charts:
http://graphs.headphone.com/graphCompare.php?graphType=0&graphID[]=853&graphID[]=4163&scale=30
 
 
 
 
 
 
 
 
 
GEAR
Initial testing on an iPod touch ( 3rd Gen )
The idea with the iPod is to ensure that it can drive the headphone to loud listening levels and still remain under 100% volume.  The K712 Pro did that and sounded great through the iPod touch.
 
Full review conducted on my home rig:
Sources:  PC playing 256kbps AAC or better files, Internal DVD player, iPod Touch 3rd Gen.
DAC:  Grace Design m903 ( 24 bit mode )
AMP:  HeadRoom BUDA in single ended mode
Interconnects:  Kimber PBJ RCA and Seismic Audio Balanced patch cables
 
INITIAL TEST TRACKS
Check Corea:  Three Ghouls, Part 1
Karsh Kales:  Longing
Maroon 5: Won’t Go Home Without You
Michael Jacskon:  Wanna Be Startin’ Somethin’
Patricia Barber:  Dansons la Gigue
The Beach Boys:  Surfin’ USA
They Might Be Giants:  Spiraling Shape
 
FIRST IMPRESSIONS
A quick inspection reveals some much appreciated updates.  The headband no longer has bumps on the inside and is made of leather, the cable is detachable, and the earcups are extremely comfortable.  Many of the aspects appear to be "rehashed" from prior designed making many listeners skeptical or downright unhappy with the design choice.  For me it is more about judging a headphone on its own merits than knowing its history and making a preformed guess as to how they sound.  The design is solid from form, fit, and function.
 
From my iPod the test tracks were very involving and the improved bass was noticed.  I gave the K712 Pro an initial listen in my laser lab where things become quite noisy.  With my head deep inside the confines of my flow booth I had to set the volume to 70% which seemed pretty high for the advertised sensitivity and impedance.  Even on my home rig the BUDA remained on high gain and about set to 1/3 output.  That in mind they did sound quite good at this volume.  Things sounded great and the comfort improvements are huge in my book as I hardly noticed I was wearing headphones while working.
 
LET’S TEST THIS THING
Check Corea’s Three Ghouls, Part 1:  This track tests quickness, realism, and treble.  It also tests how up-front sounding a headphone can be.  The K712 Pro sounded full, quick, and perhaps a tad lean on the piano.  They lacked a little of the rough attack the headphones like the HD650 deliver with this track.  Then again the kick drum was much more realistic with the K712 Pro than the HD650.
Karsh Kale’s Longing is a track I use for general imaging and engagement.  As Tyll will tell you sometimes how a headphone makes you feel tells a lot about the headphone itself.  The separation and sense of space is just awesome with the K712 Pro.  From the bass to treble there is a very nice cohesion and fluidity making this track very enjoyable.  The K712 Pro sounds less tinny than the HD650 here and revealing to the sound image.
 
Maroon 5’s Won’t Go Home Without You:  This is a track I typically use to test crossover issues with speakers and IEMs.  It also gives rise to issues with male vocals and too up-front sounding headphones.  Most AKG K7xx headphones have some issues with up-front sounding drums and vocals.  I would say the K712 Pro is very similar sounding as the HD650 in this regard, but the airy bass on the K712 Pro is just awesome.  The K712 Pro is smoother than the HD650 on the vocals removing the edginess.
 
Michael Jacskon’s  Wanna Be Startin’ Somethin’:  Another track testing the up-front nature of headphones.  It also tests treble and vocals as with some headphones like the AH-D2000 and K701 can be harsh.  No doubt here even though the K712 Pro sounds nice with this track they are bright and up-front.  The HD650 removes the harshness at the cost of some realism in the bass guitar.  If you are an engineer looking to find issues with treble these are good headphones for that.  As for home listening the treble may find itself EQed down a bit.  Dropping 315Hz, 400Hz, as well as 3150Hz and 6kHz tamed the K712 Pro a bit.  No surprises here as this is what I typically view the sound signature of most AKG headphones.
 
Patricia Barber’s  Dansons la Gigue:  A great tack to test separation, bass, and female vocals.  A headphone like the Grado RS-1i struggles here as things become too one dimensional.  The bass blurs into the mids and further into the treble.   The richness of the guitar sounds spectacular with the K712 Pro.  It is possibly the best sounding dynamic headphone in this regard.  The HD650 begins to blur the guitar into the mids and there is a strange blurring of the vocals with the HD650 that I simply do not hear with the K712 Pro.  The K712 Pro is definitely a soft jazz headphone.
 
The Beach Boys’ Surfin’ USA is a track I use to test how even a headphone may sound.  Much like using Pink Noise it reveals any glaring issues like a lack of midrange smoothness, imaging, and even quickness.    The AKG K712 Pro removed the excess hiss on the letter “s” heard on the HD650.  Again here it was more about what headphone signature works well with the given track.  I liked the K712 Pro more as it sounded less colored and perhaps even laid back to that signature of the HD650.
 
They Might Be Giant’s Spiraling Shape is a track I use to test male vocals in detail, how the kick drum resonates, as well as test the metallic splash of the crash cymbal.  Here the HD650 sounded really colored compared to the AKG K712 Pro.  The Pro sounds much more even from the kick drum through the vocals.  The HD650 blurs the vocals into the bass.
 
If your music collection or production work consists more of acoustic guitar, drum, and vocals the K712 Pro scores excellently and would be my preference over the HD650.  For music like hard rock the Pro may wield a bit too much bite and up-front sounding midrange compared to the HD650.  As with many AKG headphones this will diminish slightly over time.
 
CONCLUSION
The AKG K712 Pro is a headphone that sounds very good and speaker-like.  The added bass is actually very impressive on particular tracks like Dream by Kroke.  Bass not found in the other AKG headphones that I have heard.  It is a headphone I find myself listening to over the HD650 at times because with certain tracks is sounds more full and pleasant.   In the end it is really about preference, but rest assured the AKG K712 Pro is an excellent and amazing sounding headphone.
 
At $499 I cannot help but feel that this headphone is on the expensive side.  In some areas it improves upon the sound of the HD650, but in other areas it remains hard to listen to due to the peaks at 2kHz, 7kHz, and 8kHz.  The build quality is really good and the headphone will look great with any home or production setup.  As others have mentioned if the price drops to $350 I think others including myself would be all over the K712 Pro, but at $499 you start looking at the Q701 and Momentum.  It definitely looks like AKG is targeting the somewhat lean $399 - $499 market, but I would like to see this headphone around $299-$399.
 
I also want to comment on the fit.  The K712 Pro is very comfortable and can be worn for hours without fatigue on the outer ear or top of the head.  The earcups rest a bit low on my head making me wish I could further adjust the headband.  The somewhat common issue with the elastic on the auto adjusting headband may wear out like their other headphones, but keeping good care of your cans should prevent that from happening.
 
My brief experience with the K712 Pro has been a good one and with more listening I imagine it will only improve.

FURTHER TESTING / ENJOYMENT
As with many headphones the more you listen to them the better they sound.  This is definitely true of the K712 Pro.  Listening to Photonic Phonic by Magic Sound Fabric via my iPod is extremely enjoyable.  The clarity, sense of space, and generous bass groove is very inviting.
 
Listening to Go Daddy-O by Big Bad Voodoo Daddy shows how quick the K712 Pro.  The cymbals are super quick and the horns are tame.  Again here the bass is something in balance rather than lacking.  These are quick!
 
John Williams' Christmans at Hogwarts is another pleasure.  The entire orchestra is in balance and the sense of space with the K712 Pro is very pleasing.
 
Mo' Horizon's Foto Viva is outstanding.  The engaging groove heard on the K712 Pro is very fun.
 
Pink Floyd's Goodbye Blue Sky is another track showing off the midrange and clarity of the K712 Pro.  The guitar is extremely realistic and the vocals are not lost.
 
Cello song by The Books sounds amazing.  The sense of space and the idiosyncrasies heard in the background are quite clear.
 
Daft Punk's Solar Sailer is a testament to how low this headphone can go.  There is some serious open rumble in this track and the K712 Pro is not shy to deliver.
 
I updated the overall rating from a 3.5 to a solid 4 because in many respects the K712 Pro is much more speaker-like than the HD650.
 
Vs. AKG Q701 and HD650
There is no doubt that there is something amiss with the Q701's midrange.  Piano, vocals, and the overall presence of the midrange on the K712 Pro is much more natural sounding.  The Q701 vocals, heard on Maroon 5's Won't Go Home Without You sound like they are coming through a mic that is coloring the midrange.  It simply does not sound natural at all.  Going from the Q701 to the K712 Pro is pleasing and reduces the listening fatigue from the Q701.  The bass boost on the K712 Pro is very much improved over the Q701.  The bass guitar is loud and clear instead of very recessed with the Q701.
 
On tracks like Patricia Barber's Dansons la Gigue the difference is subtle.  The vocals and bass are a bit more pronounces on the K712 Pro, but both sound very good. 
 
With Slaid Cleaves' Beautiful Thing the Q701 comes off as slightly harsher, but the K712 Pro smooths out the vocals just a touch more than desired.
 
Listening to They Might Be Giants' Spiraling shapes shows other similarities, but the Q701 has more obvious treble in vocals.  The echo in the vocals is easier to make out perhaps hidden slightly in the bass of the K712 Pro.
 
I decided to conduct a blind test using The Beach Boys' Surfin' USA.  Although it was pretty difficult to pin down which I preferred right away with a little time it became apparent that the K712 Pro had my preferred midrange.
 
The bass is really where I started to focus once the midrange differences were established.  Juno Reactor's God is God gave rise to some clear differences.  On my stereo system with a nicely tuned sub this track has some serious rumble.  Some headphones cannot reproduce the low end rumble this track delivers.  The Q701 sounded good here, but on the lean side.  The K712 Pro immediately produced better bass reproduction and rumble.  Listeners should know that the HD650 also bested the Q701 in the bass department.  If anything the HD650 has better resolution on this track than both.
 
This made me move onto Mike Clark's T's Boogaloo where the bass is a little more obvious and detailed.  Some of the air was missing on the HD650 in the very beginning.  The air is back using the Q701, but the slight thump the K712 Pro deliver is missing.  I have to believe that the emphasized bass is intentional in this track as almost every jazz / soul song I have ever heard in person has a slightly emphasized bass guitar.  It sounds more live with the K712 Pro.
 
The thunder in Dream Theater's A Nightmare To Remember has more body with the K712 Pro compared to the Q701.  The HD650 was much closer to the K712 Pro here and either suits this track well.
 
Vs. the Denon AH-D2000
The AH-D2000 is an excellent closed headphone and possibly the best I have listened to so far.  On tracks like Kate Havnevik's So:Lo the Denon is simply too boomy with bass bleeding all over the balance of the rest of the track.  This occurs again in Glenn Zervas' A Thousand Shades of White.  The low notes from the guitar are boomy on the Denon, but with the K712 Pro there is a very welcome balance to the sound.  At higher volumes ( just above long term levels ) Final Fantasy's None of You Will Ever See a Penny reveals a blury midrange image on the Denon while the K712 Pro has a slight brightness common with the K701 and Q701.  Something that a healthy -4dB EQ from 2kHz to 6kHz tames nicely.

The airy nature of the K712 Pro lends itself to tracks like MC 900 ft Jesus' Gracías Pepé whereas the Denon is lost and enclosed.

On Bluetech's Enter the Lovely the Denon added a slight coloring of the midrange sounding a bit tinny.  The AKG K712 Pro adds a nice digital rising edge to the beats heard at 2:58 unlike the Denon which feels decayed.  A fun track with both headphones, but the AKG K712 Pro is definitely the more neutral sounding.

My goal here is to compliment the bassy and somewhat fun sounding Denon with a more technically correct headphone like the K712 Pro.  Leave the thumping and enclosed tracks to the Denon and add air and crisp treble with the AKG.
 

Vs. the HE-500
Frequency Charts
http://graphs.headphone.com/graphCompare.php?graphType=0&graphID[]=4163&graphID[]=3241&scale=30
 
Pink Noise Test
Source:  Ayre Acoustic’s Irrational, But Efficacious CD
Compression: None
 
The AKG sounds peaky in the sub-bass and treble while the HE-500 is much more even across the entire frequency range.
 
Brown Noise Test
The AKG again has a peak in the sub-bass while the HE-500 is darker sounding which is what I would expect from the Brown downward slope in the frequency response.
 
Music Testing
 
Marcus Miller’s Gorée (Go-ray)
This is a great track for quickness heard in the cymbals.   It also tests for honkiness in the sax.
 
The HE-500 and K712 Pro both due quite well with this track.  The HE-500 adds some treble to the sound of the cymbals making them sound more metallic, but there is a blurring effect that keeps the cymbals from sounding their best.  The AKG K712 Pro is more up-front and reveals that harshness of some of the sax notes while the HE-500 smooths out the sax.  The sub-bass is more pronounced with the AKG K712 Pro, but the snap of bass string is lost with the HE-500.
 
Both headphones sound great with this track.  The HE-500 is more realistic with the cymbal splash while the AKG K712 Pro is more obvious with the sound of the bass guitar strings.
 
Dion’s Tarraplane Blues
This track tests male vocals, guitar, and the sound of decay within the drum machine.
 
The quick punch of the drum machine is swifter on the HE-500, but the AKG K712 Pro is just about as quick.  The vocals, being more up front on the K712, are more enjoyable and intimate compared to the HE-500.  Better matching the loudness brings the two headphones even closer together.  The sound of the drumstick hitting the side of the snare is more obvious on the HE-500, while obscured in the vocals on the AKG K712.
 
MC 900 ft Jesus’s Bill's Dream
A test track used to hear how real the drums sound and how much air is present.
 
The HE-500 sounds quicker on drums and less sub-bassy.  There is some treble extension on the K712 not heard on the HE-500 most noticeably on the pitter patter of the drum head and metal sound on the cymbals.   The HE-500 shades the cymbals and pushes the pitter patter of the drums too far back.
 
Mo´ Horizons’s Soho Vibes
A track that testing everything from bass to cymbals with emphasis on the midrange vibes.
 
This track has the clearest difference between the two headphone other than the pink noise.  The HE-500 hides the metal splash of the cymbals within the sound of the vibes.  There is also a ringing sensation on the vibes with the HE-500 not heard with the K712.  The echo from the drumstick hitting the side of the snare is more rounded and smooth with the K712 and square wave sounding with the HE-500.
 
Conclusions:
Both headphones are commendable.  The HE-500 flat throughout the frequency response, but at times square wave sounding with analog instruments and blurring treble into the midrange at times.  The sub-bass peak of the K712 is very obvious on many tracks, but often presents cymbals and vocals in a more pleasing way.  There are more signs of echoes and other positional cues on the K712 than the HE-500.
 
For the price the AKG K712 Pro does quite well against the more expensive HE-500.  The sub-bass is the main problem for the AKG while the HE-500 tends to hide detail and positioning cues.   The HE-500 begins to reveal these cues at volumes above which I am comfortable listening.
The HE-500 reminds me of the HD650 sans the added treble.  It is an easy going headphone while the AKG is more up-front.
 
Additional testing:
None of You Will Ever See a Penny by Final Fantasy reveals how the HE-500 hides the sound of the reverberation of the stringed instruments while the AKG presents a more hollow and lively sound.  The HE-500 sounding square wave in nature with no decay.
 

Vs. the modified Sennheiser HD800

Mod reference: http://www.innerfidelity.com/content/diy-modification-sennheiser-hd-800-anaxilus-mod

 

I borrowed this modified HD800 from Tyll and although he thinks the mod does not drastically change the sound of the HD800, he does admit that it plays a key roll in getting the most out of a pair of stock HD800 headphones.

 

To me the stock HD800 is a bit digital sounding, Tyll uses the term “steely”.  It sounds almost too quick and trebly at times.

 

Pink Noise

I use pink noise to find peaks or valleys in the frequency response.  If something stands out or becomes harsh in using pink noise chances are it will sound that way when listening to music.

 

The HD800 sounds very smooth below 500Hz, but there is a definite peak somewhere above 500Hz that my ear is picking up on as fatiguing.  Compared to the K712 Pro which sounds much more even in the treble, but the sub-bass component is prominent.  Here it seems is a flavor choice.

 

Using Quentin Dujardin’s track 1977 I shift my focus to music listening.  The K712 Pro is very musical, sweet sounding with the guitar plucks and the wisps of ambience which appear to be the artist breathing.  The treble is very nicely neutral and the location cues from the treble are very easy to home in on.  The guitar string sound is moved to the background with the K712 Pro and obscured compared to the HD800.  I hear more of the resonance of the guitar body rather than the pluck of the strings with the K712 Pro whereas the strings are much more focused with the HD800.  The HD800 is easier to listen to with this track.

 

Using Mike Murray’s Hello Market track I move onto dynamics.   The resolving power of the HD800 and soundstage is simply amazing with the HD800.  The separation of each instrument is lost with the K712 Pro and again we hear a blurring of the midrange.  I cannot help but think that the modded HD800 softens the entire frequency spectrum compared to the K712 Pro making it easier to listen to on this track.

 

Starting up Bluetech’s Enter the Lovely track reveals other differences.  The HD800 brings immediate focus on the ticking with some brightness felt.  I hear more resonance on the ticks with the K712 Pro.  The K712 Pro emphasizes the lower frequencies more than the HD800, while the HD800 is focused on the midrange.  The K712 Pro has a definite sub-bass emphasis compared to the HD800 giving it more body there, but it still sounds blurry compared to the HD800.

 

The last track I compared these headphones with is MC 900 ft Jesus’ Gracías Pepé.  The airiness of this track is lost using the HD800.  It sounds like the HD800 has more treble focus and smooths out the track by removing some of the harmonics in the midrange frequencies.  This track makes the two headphones sound surprisingly similar which is a good think for the much less expensive K712 Pro.  I have no preference on this track.  Again this is coming down to focus.  The HD800 focused on attack and treble separation while the K712 Pro is more midrange centered and revealing in airiness.

 

The HD800 appears to have fewer reflections in its resonance making it very revealing and resolving.  The K712 Pro is blurry by comparison.  The primary differences between these two headphones are the resolving power of the HD800, the sub-bass impact of the K712 Pro, and the blurring of the midrange on the K712 Pro.  If money were no object I would easily go for the HD800.  Everything from my reference collection I throw at it sounds amazing.  The K712 Pro does a great job, but compared to the HD800 one can hear the blurring.

 
HOW DOES ORCHESTRAL SOUND WITH THE K712 PRO?
Giuseppe Sinopoli and The New York Philharmonic's Pictures At an Exhibition sounds very full, realistic, and wonderful with the K712.  The reverberation of the brass, the kind thump of the bass, and even the horns are all in place.
 
Moving onto the Les Sylphides VIII: Valse by the Berliner Philharmoniker Herbert von Karajan is elegant, pleasing, and truly mastered by the K712.  The fullness of the track along with the minute idiosyncrasies heard are put to good use with the K712.
 
Leopold Stokowski and the original Decca recordings 1965-1972 of JS Bach's Prelude in E-Flat Minor is simply stunning with the K712 Pro.  Full, vibrant, and well balanced throughout this track is something that really drives emotion.  Nothing sounds out of place, but I feel that the strings are uneven sounding and unrealistic with this track.  I do think it is more the recording than how the K712 reveals the strings to be.  The Dialogue of the Wind and the Sea from this album is also worth a listen.  The imaging is spectacular and the low bass rumble is something not commonly heard with other headphones.
 
Alaine Fink and George Vosburgh's Intrada for Trumpet and Piano is quite mellow for such a vivid trumpet piece.  The imaging for the piano is also quite good and not lost among the trumpet's more in your face attitude.
 
Moving into a vocal recordings I started up Veronique Gens' Mass in B Minor, BWV 232: Laudamaus.  Again the detail and the hints of echo, the vibration of the strings, and the closeness of the vocals were all amazingly reproduced with the K712.
 
The English Suite No. 2 in A Minor, BWV 807: V.Bouree I/II by JS Bach from Menuetto Classics is about as close to a harpsichord as I have ever been.  I felt as if I was there when it was played.  The Suite for Violoncello Solo No. 1 in G Major, BWV 1007: I, Prelude by JS Bach is another extremely realistic piece on the K712.  This track is a must have for classical listeners!  The Complete Cello Suites from Klaus-Peter Hahn is really a bargain and well worth looking into if you want to round out your collection.
 
I think the K712 Pro is an excellent if not amazing headphone for classical listening.  It adds a sense of vibrance, life, and detail not heard in many other headphones.
 
WHICH DO I PREFER AND WHY?
I must say the K712 Pro holds its own.  It may be bassy on some tracks, but to me this is a good thing.  The pleasing midrange is extremely easy to listen to and discernibly more even than that of the Q701.  On some tracks the Q701 is more airy with a definite issue with the midrange.  The HD650 and K712 Pro trade off every other track I throw at them as to which I prefer, but on the occasional track the HD650 sounds strangely thin in the bass.  If you are looking for a more budget headphone the HD650 can often be found on sale making it truly enticing.  The K712 Pro offers better clarity and a less blurry image on the low end.  The Q701 has some issues with the midrange and slight lack of bass.
 
Need a track to figure which you prefer?  Try Medeski, Martin & Wood's Chubb Sub.  The bass is ever so slightly blurry with the HD650.  The slight harshness of the Q701 also blurs the low end.
 
All three are excellent headphones and this test really brings it home how great each is in their own right.  To me the K712 Pro does what the others strive for only better.
 
IS IT JUST THE PADS THAT CHANGE THE SOUND?
I tested the Q701 and K712 Pro without pads.  I simply left off the pads of each and did immediate swap testing.  My BUDA continuously drives both headphones during this test.  It looks like the drivers are the same, but the resonator is different.  The Q701 has a noticeably different and somewhat tinny sounding midrange compared to the K712 Pro.  Both sound much closer to one another than I initially thought would be the case suggesting that there is no doubt benefit to the new pads.  To my ears the change in sound is more than just the pads, but the pads make the biggest difference.  With the K712 Pro pads on the Q701 there is more meat to the bass, but the mids did not sound quite right.
 
The AKG K712 Pro still sounds its best with the K712 Pro pads, but if you want a poor-mans version of the K712 Pro adding these pads to existing Q701 / K701 will get you very close.
 
I did this testing with Marcus Miller's Redemption and Mo' Horizons' Foto Viva.  It took me these tracks to start hearing the differences.  I think initially I had the Q701 pads installed incorrectly as it sounded worse.  I installed the pads on the Q701 with the thicker side facing back and the Q701 returned to its former glory.  Again it came down to how much meat was on the low end and something in the mid range on the Q701 is tinny in comparison, but it is close.
 
A FEW OTHER TRACKS OF NOTE
Emiliana Torrini's Ha-Ha ( Vocals )
Santiago Vazquez's Azul Sangre ( Neutrality and soundstage )
The Doobie Brothers's A Brighter Day ( Quickness on drums, bass guitar )
Thelonious Monk's Rhythm-A-Ning ( Speed, Jazz )
 
2016 Update
After much debate I decided to include a long-term listening update. The primary idea behind this is to give a brief review of the AKG K712 Pro after owning it for years. The score of this entire review has been adjusted due to this update.
 
Due to the rather weak adjustment system on the K712 Pro the fit comfort score has been lowered. Several users including myself find that the earcups rest too low on the ears not only making it uncomfortable, but the sound suffers too.
 
The price seems high considering it is a tuning of the K701(2). It would have been an excellent choice to add a few more dB of bass to separate it from the other K7yy line of headphones.
 
With planars like the HiFiMAN HE-400s and HE-400i within the price point of the K712 Pro it is hard to recommend. These planars sound more coherent, have larger drivers, are more comfortable, and deliver deep linear bass.

Fischer Audio FA-003
Recommend: NO
Price: $180
 
I would like to thank Tyll Hertsens for lending me his pair of FA-003 headphones for this review.
　
Initial Impressions:
If you take a look at the charts you cannot help think that they will sound a little like the Audio Technica M50. The wavy midrange jump and the peaky impulse response had me worried.
 
Looks:
At first glance I was not sure if they were headphones or earmuffs for cold winter trecks. Once I placed them onto my noggin I could tell there was some serious engineering here. Things were well made and nothing was an immediately obvious weak point.
 
Fit:
The FA-003 is one of the more comfortable headphones I have worn. They look and feel big, but once they are on they melt away.
 
Comfort:
They were amazingly comfortable sans a bit of pinch that I knew could be relieved with some stretching over a tissue box for a week. The headband is really comfortable, but the strength of the hinges feels a bit weaker than the M50.
 
Design:
The earphones appear to be well made from synthetic materials. The ear cups are plastic with some nice looking metallic veneer. The headband adjusts easily and the cable is detachable which is a huge plus in my book.
 
Sound:
The sound is definitely dark with an audible midrange attenuation. I heard this easily while listening to John Williams' Double Trouble. It sounded clear and neutral until I switched to my AH-D2000's and realized there is a big dip in the midrange of the FA-003. The soundstage is wider than the Creative Aurvana Live and the highs were crisp, be it slightly rolled off.
 
Bass:
The bass was deep and not as boomy as other dynamic driver headphones. It extends quite well but using Collective Soul's "Forgiveness" gave me a sense of attenuation in the low end. There was some audible roll off in the bass. The bass was no where near as deep or impactful as the AH-D2000 or M50.
 
Mids:
The mids were fun. They were airy and extremely enjoyable with percussion. The slight echo that is common listening to drums was easily heard and enjoyed. Due to some dips in the midrange many tracks were not as wide as the AH-D2000. I especially heard this on Yoshida Brothers' Aiya.
 
Highs:
Much like the midrange the highs suffered from some extreme dipping and roll off. Coleman Hawkins & Duke Ellington' Wanderlust was lifeless sans the saxophone. I will admit that the sax and trumpet sound very pleasing through the FA-003.
 
Imaging:
The image was big, but not very. Using Buddy Miller & Julie Miller' Long Time, which is my favorite test track for imaging and soundstage, sounded too laid back and muffled.
　
Conclusions:
I think the FA-003 is a super comfortable headphone and perhaps with a few EQ tweaks could be much better sounding. For me the M50 was a far better headphone and did better with both soundstage and the high end.  There is a lot that the FA-003 has going for it.  The comfort is outstanding, the design is well thought out, and the comparative cost to some alternates is very reasonable.  For me, however, there are some issues with the sound out of these cans that are extremely apparent while A/B testing with other cans within its price point.

Sony MDR-EX600 Review
Recommend: No
Price: $199
 
I borrowed a pair of these from Tyll for review. These are the MDR-EX600 which are commonly faked on ebay.
 
I must admit that the charts are actually quite impressive. They are very flat from 5Hz up to 1200Hz and have some nice peaks in the treble.
 
Looks:
The case is very nice but a tad large. I would end up placing the earphones in my pocket due to the size of container they come in. The way the earphones wrap around to fit inside the case is a bit ridiculous. It really could not be any more inconvenient. The earphones themselves look and feel nice and the cable is just long enough for portable devices.
 
Fit:
It took me a while to get just the right fit. I press them in then wrap them around my ears making it a bit odd to get angled into my ear canal properly. Non of the included tips worked well. I installed a pair of T-400's I had laying around which worked a ton better. Due to the sheer bulk of the driver housing they feel like they would pop out of my ears if I move much, but after exercising with them they stayed in place just fine. Keep in mind this was with T-400's not the default tips.
　
Comfort:
There were no comfort issues once I got them into my ear canals, but I was a little uncomfortable wrapping them around my ears and trying to figure out how to make them fit correctly. They are really bulky and take some getting used to while they are in your ears.
　
Design:
The earphones tested had a crack in them already along the post where the cord first plugs into the earphone. The cord is not microphonic at all. The cord is terminated into a 1/8" plug at 90 degrees and fits nicely into my iPod touch that has a plastic hard case on it. Not all cords fit this well. The cord is very thin passed the ear pieces and I imagine it splitting at th plug end after a few tangles.
　
Sound:
With any of the default tips the sound was mediocre at best. Once the T-400's were in and the fit adjusted the sound was really nice.
　
Bass:
The bass was deep and not as boomy as other dynamic driver earphones. It extends quite well and using Collective Soul's "Forgiveness" gave me a taste of good extension. There was some audible roll off in the bass, but it was certainly clean and deep.
　
Mids:
The mids were pleasant with a slight tilt down toward the treble which made some tracks a little tinny. I found this so listening to the Heartless Bastards "Pass and Fail". I also picked up on some sibilance in the mids using the "Forgiveness" test track once again. Perhaps due to the driver position I found I had to turn up my iPod quite a bit to get a high quality sound out of the EX600, but at that point I could only listen for a few minutes before having to turn it down.
　
Highs:
highs were not as swift as I like. They were more extended than my M2's, but still a tad bland and lifeless. In Coleman Hawkins & Duke Ellington's "Wanderlust" the high hat was just a tad too much rolled off for me. The snare felt a bit dim too.
　
Imaging:
The image was better than a lot of other IEM's, but fell behind my M2's. I did appreciate the airy sound the EX600 could bring to tracks like "Plenty More" by the Squirrel Nut Zippers. The image of Buddy and Julie Miller's "Long Time" was a bit flat and really did not impress me like the M2 can.
　
Tracks that sounded really amazing through the EX600:
"I Will Never Be Untrue" by The Doors
"Summer" by Great Big Sea
"Yellow Submarine" by the Beatles
　
Tracks that sounded too full or loud with the EX600:
"I'm Not Your Toy" by La Roux
"Rock This Town" by The Brian Setzer Orchestra
"Sideways" by The Birthday Massacre
 
Conclusions:
Although the Sony MDR-EX600 is a great sounding IEM it lacks the sound stage and design qualities of the M2. I found the EX600 much like the HD-650 in that it takes higher volumes to bring out a pure sound, but at that point my ears started to hurt. At the $199 price point there are many other great IEM's including the M2, UE700, and HiFiMan RE262. Even the Fischer Audio DBA-02 will give the EX600 trouble.
　
I will admit that if the cord was a bit more beefy, the cracking issue addressed, and Comply T-400 tips included with the EX600 they would be a perfect fit into my IEM library.  With Comply T-400 tips I recommend these over the Monster TurbinePro Copper.

Creative Aurvana Live

Cost: $60 US
Recommended: YES

Compared against my Audio Technica ATH-M50's

Looks: Simply designed with no extra flair sans some reflective ear cups. Each ear cup is clearly labeled for left and right. Leather ear pads, a slim headband, and 3ft rubber insulated cord finish off the Aurvana Live

Construction:
The cord is nice and durable and the stereo connector is small enough to fit into my ipod ( with plastic cover ). The cord is Y-terminated into the ear cups and is not removable. Both ear cups swivel using two small screws per side which is nice, but I would still use some Loctite to ensure not losing the screws. The headband is slim and not uncomfortable.

Isolation:
For being circumaural they really could isolate better. I can hear the fan on my computer 2 ft away whereas on my M50's dampened the fan sound much better.

Comfort:
I have relatively small ears and the ear cups did touch the sides of my ears a tad making the Aurvana Live a bit uncomfortable. The headband is also minutely uncomfortable from being very slim, but it was not as bad as most Grado headphones or those evil bumps on the Q701 headband. After a little adjusting the Auvana Live remained quite comfortable.

---

Sound

Bass: Tested using Weird Al's "Pancreas", Yoshida Brothers' "Oh My Love", and Collective Soul's "Forgiveness"

The bass on the Aurvana Live is really impressive. It goes quite deep and has some kick to it. It was a bit more up front that the M50 and went a bit deeper. It was not out of place boomy and sounded good for a closed can.

Mids: Tested using Yoshida Brothers' " Tsugaru Junku" and "Aiya" as well as Michael Jackson's "Wanna Be Startin' Something"

The mids were well represented. Due to a clear lack in imaging the mids were not spectacular, but they were not amiss. In Michael Jackson's "Wanna Be Startin' Something" everything sounded nice and even from the bass through the mids. Vocals were not washed out as with other cans of this type. Things started to taper off toward the treble compared to the M50 which was bright using the Michael Jackson test track.

Treble: Tested using Coleman Hawkins & Duke Ellington's "Wanderlust"

There treble is where the Aurvana Live starts to roll off. It is not terribly bad, just a tad colored on the high end. Where the trumpet should have been a tad piercing was a smoothness and perhaps kindness. I did like it, but noticed it being a tad rolled off for my tastes. Due to this roll off music typically lacked a kind of airiness that is found in more spacious and bright headphones. The high hat was almost completely diminished with the Aurvana Live.

Imaging: Tested using Juno Reactor's " Conga Fury" and Great Big Sea's "Little Beggarman"

The Aurvana Live did not image tremendously well. The bongo drums in "Conga Fury" were somewhat level sounding with the rest of the image and lacked the space that the M50 provides. It was not too far behind the M50, but certainly lacked the sort of airiness you can find in tracks like this with higher end headphones like the DT990.

Amping: Tested using an m903 fed via USB uncompressed audio at volume level 58

The Aurvana Live amped became a little tinny sounding to my ears. I only heard this on some tracks with my iPod, but amped I certainly hear more often.

Amped Bass: The bass tightened up and was a tad loud to my ears compared to the rest of the spectrum. It was not super boomy and out of place, just high pressure.

Amped Mids: The mids become super clear and crisp. They were more serious and real.

Amped Treble: Amped the treble nearly matched the M50's. The high hat was more present

Amped Imaging: The image certainly improved a bunch, and tracked with the improvement heard in the M50's. In fact it gained a little on the M50 once the Aurvana Live was amped. Ani DiFranco' "Cradle & All" sounded much wider. Buddy Miller & Julie Miller's "Long Time" remained too single plane for my taste, but it did with the M50 as well.

Drums and the entire mid range to treble were so much quicker out of the m903 than the iPod. "Wanderlust" was just amazing. The snare was quick and a little in your face. The imaging on the sax gave a tad bit of air not found through the iPod.

Amped Jazz: I tested Patricia Barber "Postmodern Blues" through the Aurvana Live because jazz is hard for some cans to do. Grado SR-80's for example lack the vocal clarity and separation for really fine sounding jazz. The test track sounded nice and the vocals were clear and pleasant. I could hear the bass all the way up to the chimes.

Amped Electronic: I ran with Karsh Kales "Home" because I am very familiar with the track as well as it lacking boomy and out of place bass. The Aurvana Live lacked a little quickness in the mid range that my D2000 and DT990 have, but it was certainly not bad. Again the bass pressure was a bit much for my ears, but to some it may be just fine.

Amped Hard Rock: I decided to listen to Trantric's "I'll Stay Down" for this test. It is a nice quick song full of bass, mids, vocals, and treble. Other than a slight lack of air the test track sounded really nice from the Aurvana Live.

Conclusion:
At $60 the Aurvana Live! is an amazing headphone. It is designed well and sounds great. Other than the lack of excellent imaging and crisp and well extended highs they are an amazing headphone. They sound a bit more fun amped than my M50's.

[size=10pt]Too many people first starting out in the $100 category for headphones choose the 280 as a starting point.  Without directly A/B comparing the 280 pro against other headphones at this price point is you are going to leave yourself room for much improvement.  The isolation is about all that is beneficial from this headphone.  The durability is unanimously horrid and sound quality is hugely dependant upon how to fit your head and seal around your ears.[/size]
 
[size=10pt]If you are looking at these for you first choice in "quality" headphones I would listen to the Audio Technica ATH-M50's before making your final decision.  If you like In-Ear type headphones try the Brainwavz M2.[/size]
 
[size=10pt]One interesting fact about these headphones is that the outermost part of the shell is too thin which appears to dampen the sound a bit.[/size]
[size=10pt]http://www.youtube.com/watch?v=uHkb4bhdnRA[/size]

I have been looking for a headphone that mates well with my Grace m903 which tends to sound a tad bright. My HD-650's just did not cut it. I tried a pile of expensive headphones and the only one that I thought sounded amazing was a pair of LCD-2's. Being outside of my price range I searched for something as close to that sound as possible. After listening to many headphones I settled on the AH-D2000 for two main reasons:
 
1.) An employee at headroom has two pairs of them. One for work and one for home.
 
2.) The AH-D2000 sounded as close to the LCD-2 as any other headphone.
 
Once I received them and plugged them into my m903 I realized what a synergy they created.
 
Build: Amazing, light, and high-quality ear pads
 
Bass: One of the best bass ranges I have heard period. Better than HD-650, HD-800, ATH-M50, as well as T5 and T1.
 
Mids: Excellent and well balanced. Nothing was missing or out of place
 
Highs: Not bright at all and the cymbals as well as bells are amazing
 
Cord: As Dave Rat noticed when he received his pair: "one of the best headphone cords I have ever seen" and I certainly agree. The cord is braided and thick enough to survive wear and tear, but not too thick to hinder its manipulation and placement.
 
Impedance: 25 Ohm so every amp out there can drive them whether that are constant current or constant voltage. This is a very flat impedance vs frequency so no region of the audible spectrum is dampened. This is the primary problem with the HD-650.
 
Sensitivity: 106dB which allows you to listen at moderate levels and not feel as though you have to turn up your amp just to get the sound you want.

  May Your Next Set be the LCD-2
 
If you slap two enormous earcups onto a thin headband you start to approach just how large the LCD-2's are. After all not every phone out there gives you greater than "6 square inches of active driver space". The picture really does not tell the whole story.
 
I was a little hesitant to try them when Tyll Hertsens handed them to me. I really was a bit shy of such a ridiculously sized phone. So I started with some HE 6's ended up being a beast to drive. At a mere 83.5 dB sensitivity it is no wonder why you have to turn your amp up to 70% volume to start to get the full sound of the HE 6. I quickly moved onto some T5's which were easier to drive, but still had that recessed soundstage that I cannot stand. It is bad enough to have headphones project the sound back into your head which really does not simulate real hearing phenomena, but to have it exaggerated is just unacceptable. In went the HD-800's and boy was the comfort and build quality felt. They were awesome to wear, just lifeless to listen to. Their deeply laid back imaging, their impedance dominated low end, they just leave you unimpressed.
 
Perhaps these colossal headphones should be tested, I thought while staring at the LCD-2's handed to me earlier.  In they went. Their size quickly diminished as the smooth and immediate bass began to oscillate my eardrums. The mids were crystal clear, and the highs were nicely rolled off. The bass was an abyss.
 
The harder I drove them the better the highs became. The detail on La Roux - [La Roux CD1 #07] Cover My Eyes was simply awe-inspiring. The soundstage in Michael Jackson - [The Essential Michael Jackson CD1 #06] Ben (Single Version) was outstanding. I could here the distant cymbals which put my head in the middle of the studio. When Patricia Barber - [Verse CD1 #04] Pieces was playing the kick bass was airy and deep.
 
PROS:
The sound quality is outstanding and the best among the auditioned headphones mentioned in this review. The soundstage is immense. The sonic clarity is one of a kind. The price even at $945 US is fantastic. The bass is the best I have found in a headphone that was not over emphasized. The mids were true and blissful. The design is pleasing and you know there are some expensive elements to the headphone. The cable is well constructed and replaceable.
 
CONS:
The sheer weight and size of these headphones place them dangerously close to being full sized speakers. The highs can seem a touch too rolled off and the same goes for vocals.  The clamping force combined with their weight made them a bit uncomfortable especially on the cheekbones.
 
This is the first set of headphones that made me truly suspect what I was hearing was the way the music truly was. 
 
Testing:
Foobar2000
m903 fed via USB
Volume set to 57
261kbps bitrate files
 
Update August 2012
It as found in late 2011 and early 2012 that both the LCD-2 Rev 2 and LCD-3 had some driver issues.  Tyll Hertsens worked on measuring it and many of us heard the issue.  It is a combination of blurring and lack of treble response that is the issue.  In August of 2012 Tyll gave me a set of LCD-2 Rev 2 and LCD-3 that were very recently manufactured.  The LCD-2 Rev 2 has some blurring, but the performance was a definite improvement over my older LCD-2 Rev 1.  The LCD-3 was again an improvement over the LCD-2 Rev 2 with hardly any noticeably blurring.  The LCD-3 tested in August 2012 sounds amazing and easily remains my favorite headphone to date.

Philips SBC HP910 Headphone

The head-fi ratings are based on the amplified sound.

Let me mention that the frequency response range is from 5 Hz up to 32k Hz meaning the bass is much more extended than one may initially expect.

Straight out of the box you notice that care and thought went into the design and functionality of the headphone. The box is well organized and the headphones come with a 1/8 to 1/4 inch adapter. The earcups are soft blue felt and the headband auto-sizes to your noggin. They fit tremendously well and are never too tight. The earcups are large enough for very large ears and nicely sized for someone with small ears. When you wear them you hardly feel them on your ears or on your head. The headphones themselves feel a tad on the cheap side in that they are so light. The plastic feels hollow but so far they have lived up to the test of time. I really enjoy their fit and moderate detail. I have had these over a year now and really enjoy them. Here is why.

Provided are two reviews. The first of which is what the headphones sound like unamped and the second is what they sound like amped via Grace Design m903.

Detail:
Unamped all of the frequencies are adequately represented. The bass is rolled off, the mids shine true, and the highs bright.

Amped the frequencies level out tremendously. The bass is deep and impactful. It reminds me of a pair of SR-80's I had with over 500 hours on them. The bass is just a joyous addition to your listening experience.

Soundstage:
Unamped the soundstage is a bit low and one dimensional. It will bore you.

Amped the soundstage greatly opens up and the depth of the sound field becomes deep, rich, and full of life. To really let them shine listen to Buddy Miller & Julie Miller - [Written In Chalk CD1 #05] Long Time. This will show you how wide the soundstage can be.

Distortion:
This is not a movie or video game headphone. With these two types of media the headphones seem to crackle a bit. It was subtle, but there. I was unimpressed by the ease of distortion found in these cans from these two sources. With music on the other hand I had no problems. Even listening to The Dead Weather - [Sea Of Cowards CD1 #10] Jawbreaker did not distort.

Impedance is a tricky thing. It is not only the resistive component of the headphone, but a combination of other factors as well. Sensitivity, impedance, and the performance of the headphone frequency response curve as a function of impedance play a huge roll in the headphones reaction to amplification. When I went from the output of my computer's audio headphone output I was somewhat displeased with the HP910's frequency response. Once I amped them up a bit with my m903 the sound was just short of life changing. The bass grew in magnitude a hundred fold. The highs were mellow but nice. The mids were right between which is where they should be.

I recommend trying Grado's SR-80i and Audio Technica's ATH-M50 if you are looking to use these unamped. If you plan on running the HP910 through a nice amp then by all means take a purchase a pair. I can almost guarantee no disappointments. Sure they are not going to rumble your head senseless with overwhelming bass. The bass will still surprise you especially in combination with the other aspects of the audio response.

Here are the numbers both unamped and amped.

UNAMPED:
Bass Extension 4
Bass Impact 2
Bass Quality 2
Mids Quality 6
Highs Quality 6
Soundstage 5
Detail 6
Portability 4
Isolation N/A
Comfort 9
Durability 5
Improvement with Amplification 8

AMPED:
Unamped:
Bass Extension 7
Bass Impact 6
Bass Quality 6
Mids Quality 6
Highs Quality 6
Soundstage 5
Detail 6
Portability 3
Isolation N/A
Comfort 9
Durability 5
Improvement with Amplification N/A

-- 2015 Edit --
Lowered the score from 4-starst to 3.5 because of its technical flaws, bright sound, and colored signature

--2019 Edit --
Lowered the score from 3.5 stars to 3 due to definite lack of bass extension and poor fit system.

What is it?
The Grace Design m903 reference headphone amp / DAC is a device that is typically used in audio production / audiophile setups to take one audio source and give life to some other audio device. In my case I let it drive my HD-650 headphones with stock cable.
 
Here are a few things to note prior to reading any further. My headphones have been fully burned in for over 150 hours which is standard for Sennheiser products so the audio response from your setup may differ from mine.
 
What is inside the m903 anyway?
Courtesy of Michael Grace
DAC:  PCM1798 ( lower power usage, a tad more noisy than the 1792/1794 )
Current to Voltage:  THAT1570
High Pass Filter:  OPA1612
The DAC power supply and line out are separate from the head amp power supplies
The input clocking is the same as the m902
Volume Control: Cirrus CS3318
The CS3318 has 7dB less noise than the PGA4311
 
Measurements
http://en.goldenears.net/11864
http://www.innerfidelity.com/images/AllAmpsJuly2013.pdf
 
Value:
 
For $1795 US you receive quite a package. You get a headphone amp, a speaker pre-amp, and DAC. The connectors are quite fantastic making the m903 one of the more favorable mid-range audio devices due to sheer versatility. The headphone amp / DAC is comparable to my Ultra Desktop Amp /DAC which is in the same price range.
 
Audio Quality:
As the mantra of great sounding music tells us one first starts with a decent source. I ran audio from Foobar2000 straight into the DAC via USB. 44.1 kHz Sample Rate and 160kbs Bit Rate. With a good transfer one can achieve nice audio from the mp3 format. I compared the m903 to the Ultra Desktop running nearly instantaneous A/B tests with all of the same cables, headphones, music files, and closely matched volume levels.
 
Soundstage:
The soundstage presented by the m903 is awesome and only slightly reduce in comparison to the Ultra Desktop. The mids and highs on the m903 are swift, immediate, and enjoyable. The soundstage can go from left/right, up/down, and the many combinations with ease. The audio presentation was anything but one dimensional.
Tested: Buddy Miller & Julie Miller - [Written In Chalk CD1 #05] Long Time
 
Bass Impact:
This is the only place I thought the m903 fell behind compared to the Ultra Desktop. The grace has decent enough impact, but it really had a little trouble driving my HD-650's into perfection. The Ultra Desktop does a great job at that. I did get close with the tested track.
Tested: Sean Jones - [Kaleidoscope CD1 #05] So Wonderful
 
Bass:
The bass is adequately represented and is especially so if your source contains it. Remember that the m903 is pure and true so you need a great track with pure bass in it to hear what it can really do.
Tested: Karsh Kale - [Realize #03] Tour Guide
 
Mids:
No questions here the mids were as strong if not slightly stronger that the Ultra Desktop. They were also a bit more up-front which for me was slightly fatiguing over long listening sessions. The mids were beautiful and articulate.
Tested: Ella Fitzgerald - [Verve Unmixed CD1 #07] Wait Till You See Her
 
Highs:
Another easy test for the m903. Even with my HD-650's I could here detailed and very quick highs. No problems with the highs that I could hear.
Tested: Michael Jackson - [The Essential Michael Jackson CD1 #16] Billie Jean (Single Version)
 
Quality and Design:
The box itself is not too heavy nor too light. It comes with well thought out exterior design and button layout. The back panel is well constructed and the source selector is bomber. The only gripe I had here was the feel of the volume control. It wiggles up and down easily. I would love to see / feel the Music Hall 25.2 volume knob on this bad boy. The knob grips are a bit weak as well. I found no major Quality Control issues and the 5 year warranty is simply awesome. The box it came in was very nice and there is a plastic pressure sleeve in the box to minimize shipping damage. The packaging was minimalistic much like the Ultra Desktop.  The feet that come with the unit can be tightened down far enough the start to dig into the bottom of the chassis.  I had to use some felt, an o-ring would also work, to keep the two metal surfaces from touching.  This also allows the unit to be better balanced on all fours.  Some have complained on the m902 that it will not rest level.  Mine had a similar issue until I used the felt and was able to control the tightness of each setscrew enabling me to level the unit.
 
Overall:
I give the Grace m903 an 87%. It is a very nice amp / DAC with a ton of connectivity which is why I really like it. On the other hand it runs quite hot and has a few minor issues which drops it down a peg.
 
Deciding Factors:
If you want an articulate and great sounding device with DAC and you do not mind sacrificing 5-10% of your bass range ( keep in mind you gain the mid/highs ) as well as a device that has many inputs / outputs then the m903 is for you. If it is your price point give it a try. I would test it with some ATH-M50's and be prepared to put a smile on your face.
 
If you are looking for slightly more bold sound including that nice bass impact then perhaps the Grace is not for you. In my opinion, which leans generally toward the Ultra Desktop side, the m903 is awesome. It is no wonder why Headroom has both on their site. It says a lot when a company that builds something that competes directly with the m903 carries both products.
 
Other Tested Tracks:
Garbage - [Absolute Garbage [Disc 2] CD2 #04] Breaking Up The Girl [Timo Maas Remix]
Nitin Sawhney - [London Undersound CD1 #15] Last Train To Midnight (featuring Aruba Red)
Ani DiFranco - [Canon (Essential Collection) CD1 #06] Cradle & All
Emiliana Torrini - [Me And Armini CD1 #06] Big Jumps
 
Preamp Testing:
I ran the audio from my Philips Magnavox CDC 735 5 disc Changer into the preamp be it m903 or Ultra Desktop and then into the TEAC_AG10D. I spent most of my A/B testing listening to the Solillaquists Of Sound - [2009] No More Heroes which is a decent hip hop album that I do bass and treble extension testing with.
 
After hours of listening between the Ultra Desktop, m903, and my TEAC's amp stage I decided the following factors were the primary difference that could be heard.
1.) The m903 was well extended in the bass. It had nice crisp mids to highs and did not introduce any audible noise into the system.
2.) The Ultra Desktop was slightly more boomy and seemed to wash out the mids a bit. The audio quality was still very closely matched to the m903.
3.) The standalone TEAC did well against these two much more expensive units. The TEAC certainly sounded different with the bass slightly rolled off and some audible damping throughout the spectrum. I was surprised at the TEAC's ability to hold its own against both the Ultra Desktop and m903.
During these tests I did discover that if you have nice monitor speakers in your living room and they are resting against the floor you may notice a drastic damping effect in the bass range. As I lowered my listening level closer to the floor the bass was much more extended and pleasant. I imagine this was due to the largest of the speakers on my Polk monitors was on the bottom and the bass sound wave was quickly absorbed into the floor. If you have speakers sitting on the floor and would like to hear a more complete sound I recommend lifting the speakers to the 3-4 foot level. You may be surprised at what you hear.
 
In comparison to the Teac's amp stages the m903 was not leaps and bounds better. I still noticed the best improvement using the m903 as an amp / DAC for my PC as I enjoyed it the most there. It gave me the most choice in sound preference. If the sound was too harsh and shallow I would go to my HD-650's. If the sound was not bassy enough I could plug in some Grados or my ATH-M50's and the balance returned.
 
Balanced Outputs with Headphones:
Ok, I know you are thinking it or have at some point; "Can I use the Balanced Outputs from my m903 and run them into headphones with a balanced cable terinated with TRS?" The answer is of course YES, but the m903 is not designed to drive balanced headphones.  How does the sound a/b to a stereo headphone output on the m903?
The output from the m903 Balanced Outputs ( L2 ) seen on the back panel will be more spacious and mellow. The mids and highs on the HD-650's I tested with were mellow and the bass was tighter. To me it turned my HD-650's into a nice mellow Grado SR-80. For some this is a bad thing comparing the price points, but to others this may give optionality. The solution to rolling off the mids and highs with the HD-650 is here!
 
Eben Grace had a few things to say about the intended use for the balanced outputs from the m903.
 
"You can run your headphones from those rear panel balanced outs, but
that's not really what they were intended for - they are really line
outputs for connecting to a power amp or powered monitors. It's not going
to hurt anything, but really the headphone outputs on the front panel are
much better suited (output power and impedance) to drive your 650's."

I tested the following tracks using direct a/b comparison going from balanced to stereo. All of the gear in between and the music was all the same even the headphone cable. I used a XLR to stereo adapter and of course XLR to TRS for the balanced testing.
 
Emiliana Torrini - [Me And Armini CD1 #02] Me And Armini
The difference between balanced and stereo was subtle, but noticeable. When the stereo out was tested the sound was clear, extended well into each side of the frequency spectrum, and articulate. With balanced outputs the sound was clean, slightly reduce on the high end, and emphasized on the low. The soundstage was a bit more colored and less harsh.
 
Karsh Kale - [Realize #08] Saajana
I actually preferred the stereo output rather than the balanced output on this track. The stereo appropriately rolled off the highs just enough and kept the soundstage intact. The balanced outputs seemed to cut too much off of the highs and mellow the mids a bit too much for my tastes.
 
Weird Al Yankovic - [Straight Outta Lynwood Disc 1 #02] Pancreas
The same held true with this track as it did with Karsh Kale. The mids were a little more in your face with stereo and the balanced made them mellow. I felt that the bass was actually tighter with the stereo output.
 
Ani DiFranco - [Canon (Essential Collection) CD1 #11] Gravel
In stereo this track is amazing with the HD-650. I would be surprised if the balanced output sounded better. The sound was not worse in balanced mode. It sounded a bit more "live" and the soundstage expanded pleasantly. If you wanted a more up front experience you could go stereo here. If you wanted a long listening session that was bit more colored and bass emphasized then go balanced.
 
Balanced vs Stereo:
In the end with an HD-650 I preferred the stereo output most of the time. It was a bit harsh at louder volume and I found myself turning the output down. With balanced outputs it was easier and less fatiguing at the same output level.
 
Should I go balanced?
I would say if you are considering balanced headphones, cables, outputs, amps, etc and you have not heard the difference for yourself I say no. The differences may be disappointing. If you have an extensive array of headphones, amps, and grow tired of your favorite cans becoming to fatiguing over time then balanced may be a good, somewhat expensive, way to achieve this. If you are out there and have connected the balanced outs from your m903 to some nice monitor speakers and would like to include your review of that particular setup here please send me your review and I would be glad to post it. I do not have self-powered monitors to test this nor will I be receiving any in the near future. Perhaps this is where the sound differences become obvious and more importantly useful, be it for fun or technical reason.
 
What do I really think?
I think that the m903 is an amazing piece of equipment.  Although it is brighter than the Ultra Desktop Amp/DAC it has just as much fun powering the top tier of headphones.  Personally I feel a wonderful balance with a dark headphone like the AH-D2000 or the DT990 with the m903.  These headphones would otherwise be perhaps too bassy.  The thoughtful technology found within and performace out of the m903 is just outstanding.  I think Grace Design prides themselves on their masterful m903 and that says a lot from a company that makes some really high end gear.  I find the customer service there top notch and honest.
 
2013 Update:  Driving a Balanced Headphone Amp and m903 Amp Measurements
In late 2012 I acquired a balanced headphone amp.  I chose the Balanced Ultra Desktop amp ( BUDA ) from HeadRoom as I am already familiar with the Ultra Desktop Amp sound.  The reason for the implementation of the BUDA was to help improve upon the low end reproduction on the m903.  I ran extensive tests going between some Kimber Kable PBJ RCA connectors and some inexpensive, but high quality, Seismic Audio XLR to TRS patch cables.  Both the Grace m903 and BUDA are capable of handling balanced and unbalanced signals.  To my ears the only difference between the balanced and unbalanced modes was a 6db increase in sound level in balanced mode.  Audibly the signals appeared identical which makes a ton of sense when you look at how each is utilized.
 
Due to the lack of low end on the m903 I suggest using it as a DAC more than a headphone amplifier.  Even the JDS Labs 02+ODAC Combo sounds just as good as the m903 at nominal listening levels as far as the amp is concerned.  Tyll Hertsens over at Innerfidelity.com measured the Grace m903's amp performance and I have provided a link to that below.
 
http://www.innerfidelity.com/images/AllAmpGraphs.pdf
 
Page 14
 
Compared directly against headphone amps like the beyerdynamic A1 or JDS O2 there is room for some obvious improvement.  Both the A1 and O2 show better linearity seen in their SIMPTE IMD charts.  Both amps have significantly less roll of both in the bass and treble than the m903.
 
2015 Update
The m903 sound particularly great with the HiFiMAN HE-400i. Note: the pads on my pair of HE-400i's have been flipped so the thickest part of the pad closest to my face, not back of my head, which smooths out the up-front nature of this headphone.
 
2016 Update
Dropped the overall score to 4 stars due to its cost and loss in performance compared to less expensive two-piece kits.