AKG K3003 Impressions
Setup:
Nokia N8 digital USB > WAV > Leckerton UHA6S in my signature. UE IERM on hand for comparison with a touch of ES5. Didn't have time to reference the ES5 as much as the IERM. After spending about 3-4 days playing with the various filters and tips, I settled on using the treble filter as I believe Averagejoe did as well. While the reference filter was more forgiving I felt that was exactly my problem with it. Compared to my Reference Monitors, using the reference filter on the K3003 knocked them down a peg compared to the transparency and resolving power of my UE IERM. I ran the reference filter for a few days and was pleased that more of my recordings became more enjoyable. I was also less pleased that they became more similar sounding despite the differences I know exist on my tracks. I then switched to the treble filter which leaned out the hair above neutral bass a bit and brought up the clarity, separation and detail. Doing this required me to use the stock tips which helped to control the treble peaks inherent in the signature compared to using my typical wide bored silicon flanges. While I tried running those double flanges w/ larger bores on the reference filter to let the phone breathe more, the reference filter was still too constrictive to take advantage. As for the bass filter, um....just don't do it. It's utter crap and wrecks the phone IMHO. AKG would have done better to just include a $30 bass-head IEM instead of the filter. I tend to be severe in my criticisms but the bass filter is god awful.
General listening:
I'm noticing the K3003 is more coherent than AKG's last attempt at a hybrid w/ the K340 headphone which had much more drastic coherence issues. I don't notice the difference between drivers on the K3003 so much by looking for it (once you dial in the tip synergy) but the difference seems to pull me out of the music more often than my other phones. It may even add a bit of brain fatigue for me, sort of like staring at a monitor too long when you're brain is more aware of the screen flicker compared to what your eyes see. You don't hear it so much as your brain knows it's there and is working to process it. Background blackness is on par, maybe slightly behind the RM. For detail and resolution, more of my worse recordings sound better and closer to my reference recordings which indicates less transparency and dynamics than the RM. Acoustic music is just great actually with slower, less complex stuff on the AKGs. Processed pop, rock and some vocal issues are sometimes too hot to handle for me.
Specific listening:
Limp Bizkit-Take A Look Around
Drums seem more fun, perhaps a bit emphasized in comparison to the RM. Some would consider this more 'natural' perhaps in timbre. Cymbals, guitar crunch, vocals giving me too much bite for long term listening. Nothing as blatantly obvious as the EX1000 spike that would occasional stab my ears but still noticeable enough to pull me out of the music and make me start thinking about the phones. Bass has a slightly accentuated character but is fun. I'd consider it a hair over neutral but less than the GR07 which I find slightly more over neutral by comaparison. A bit more bass bloat/boom and more sub bass from 50hz down than the RM. Sound is too aggressive at certain treble peaks for me. Snares, male vocals and sibilance are a bit on the harsh side. Crash is vicious towards the end when everything gets busy. There's a congested cymbal attack on my senses from 1:26-2:03 that the RM separates better. 4:15 is just painful and pretty much smeared. I don't think I'd recommended these for modern pop recordings unless you roll the reference filter and appropriate tips to tame it. In this instance, I don't find the K3003 so much revealing but rather accentuating the worst parts of this recording.
Johann Rosenmuller-Sinfonia prima
Strings are lovely and rendered well along with the Harpsichord and Oboes. With the IERM, I can hear people using their music stands more clearly. K3003 delivers more natural timbre perhaps when using the double flange and treble filter but that colors the low end by adding some reverb/decay characteristics. At least you can have the option of doing this. Both do well but I'd give the K3003 a euphonic advantage here. I find and prefer the ES5 to both however in delivering a more natural sound I'd be accustomed to live with these instruments.
The B52s-Roam, early recording uncompressed/non remastered
K3003 has more body and sounds fuller which means it's colored because it is a thinner recording. Easier to enjoy though. UERM does better to change character from recording to recording. With the ES5, even though it has more low end presence and punch/impact than either, it still renders it as being a drier recording which is more accurate than the K3003.
The Unthanks-Because He Was A Bonnie Lad
I can hear more piano resonances from the metal housing or something inside causing them to jumble and reinforce themselves. This is disturbing and neither the UERM or ES5 exhibit this behavior. I'll leave it at that, very odd.
Summary:
The K3003 is a relatively superb universal but trying to bring it up to the performance level of my UERM accentuates some inherent issues in my experience. Another review mentioned the K3003 flirting at times with becoming too hot or problematic and then pulling back just before it became an issue. I'd concur with this impression using the reference filters. Unfortunately, I decided the treble filter with stock tips would be needed for me to hear a similar level of dynamics and resolution when compared to my customs. This makes the peaks of the K3003 troublesome and potentially fatiguing over the long run. Not so much an immediate attack on the senses but more of a test of aural endurance. None of these issues are found on my UERM or ES5 and they yield equivalent or better low level detail. I can hear hiss from the tracks, not the source or amp but from the master. More precise imaging and better separation are where I can appreciate another advantage over the K3003 during my time with them versus the ES5 and RMs respectively. The ES5 is less accurate and precise in sound stage type imaging, but insanely realistic in how it renders the holographic imaging of an actual instrument. I consider this a second type of imaging. K3003 is a tad wide and flatter/linear in width but I get less sense of precise placement. The RMs let you hear sibilance from the tracks in question because they are in the mix but it's not fatigue inducing or painful. The ES5 is never fatiguing by comparison, it just wants to drench your soul in rich, textured mids without offending you in the upper registers. In comparison to the AKGs, guitar, cymbals, rides, high hats, are all more distinguishable and music is not as smeared using some of my test tracks. Trade that more 'natural' bass roundness and decay character and sub bass extension for greater bass clarity some might find less natural and that's how the UERM low end compares yet is still well rounded and present. The ES5 still renders all the detail despite having more low end and keeps more separation than the K3003. With respect to coherence, I tend to be quite sensitive especially with triple driver BA's. The UERM is the only triple driver I've ever kept and the best implementation of 3 balanced armatures I've heard but still not perfect, just not offensive. I prefer the dual driver B2/DBAs and the amazingly coherent five driver ES5. Don't ask me why the triples bother me by comparison. Even dual driver dynamics bother me like the DDM. Single drivers are obviously oblivious to coherence issues. With the K3003 there were some occasions I could tell the woofer sound from the armatures in both speed and tonality but it wasn't terrible compared to other such hybrid attempts and would likely go unnoticed by most listeners.
Pros-one of the best if not the best universal performance around. Universal nature and filters allow for tip selection to be tailored/tuned to the listeners preferences. Case is a beautiful sleek design and so are the phones. 'Natural' bass timbre if you are accustomed to the sound of a dynamic driver as a reference.
Cons-price/performance ratio not as good as the UERM/ES5 IMHO. Case can't fully close with the phones actually inside! Who does that?! Some select treble peaks may or may not bother the listener. Lack of fully integrated signature if you notice such things.