The AKG K-3003 is at least close to a landmark Universal IEM, in my view. Pricey, yes, but one of the first Universals to aspire to the heights that the best of the Custon IEM's aspire to. They are well built (though some may not like the idea of non-detachable cables) and attractive enough. But the real issue is, of course, the sound, so let's get right to it.
 
The first thing that hit me about the AKG's is that they invite comparison to full size phones in certain ways more that other IEM's. The combination of excellent coherency top to bottom, excellent but not hyped detail and resolution, low distortion, good dynamics and relative neutrality show up even good IEM's such as the Sony MDR-EX1000, Audio Technica CK-10, Ortofon EQ-7 and the like as pretenders. Let's take some of these features forward for further scrutiny.
 
Coherency 
 
These sound quite consistant as a solo instrument (piano, violin, guitar etc.) is played up and down the key/fret board. Lesser IEM's will tend to, worse case, sound uneven in amplitude or, less destructively, thin or fatten the harmonic envelope (this is where our ability to discern instruments of different model/construction comes from) under these conditions. A good example of this is the album The Virtuoso Guitar as played by Alirio Diaz on a Vangard recording. If the guitar doesn't sound like the same guitar through its range, the illusion of an expert musician playing his instrument is damaged. This coherency pays off even further during the Castelnuevo-Tedesco Guitar Concerto #1 off this album where the interplay between soloist and orchestra is preserved.
 
Detail
 
The high linearity (low distortion) of the 3003 allows one to hear deep into the lower levels of recordings without the masking effects of distortion products. This allows low level information to be heard in the mix of popular music or orchestral presentation. This allows things like the "humming along" Ivan Moravec provides in his VAI label Beethoven recordings (original on Connoisseur Society) or the various sonic manipulations on the Beatles "Strawberry Fields" to be heard clearly for what they are. This detail is not the "thrown in your face" detail of certain treble emphasized phones but is an organic part of the recording not obscured by transducer playback artifacts.
 
Dynamics
 
This is where the 3003 really excells over lesser IEM's. The combination of lack of low level artifacts and high (for IEM's) level linearity makes for a wide dynamic envelope. The Fritz Reiner RCA recording of "Isle of the Dead" (off "The Reiner Sound" album) is a great example of this. This recording starts very much hushed (as befits a piece called Isle of the Dead) but swells to quite loud crescendos. The AKG's can accomodate this without distortion (beyond the slight tape saturation on the highest peaks endemic to the otherwise excellent late '50 recording) or without compromising the soundfield by coagulating the instruments together, quite a feat for an IEM. Careful, don't listen too loud! The low distortion and high levels attainable can lead to this...
 
Relative Neutrality
 
I use this term because I am not sure what absolute neutrality would be. Neutral to the recording? Neutral to the original sound of the original performace? Neutral to some preconsceived idea how a phone "should" measure? Neutral to the your personal preference? Or some combination?
 
The AKG tends to be neutral to the recording, which tends to result in a somewhat front-of-the-hall perspective. Still neutral to the original performace, but some may like a bit of a more distant perspective as personal preference. One of my tests for the "gestalt" of the concert hall is the EMI recording of the Barbirolli Mahler 9 with the Berliner Philharmoniker. This is a good, but somewhat forward, recording of an excellent performance of this evocative piece. If the playback puts you into the hall without putting the forwardness "over the top", it's good playback. The 3003 does this, to be sure.
 
For further evaluation, let's go to the classics. I personally use Iggy and the Stooges "Search and Destroy". This is a recording made with the VU meters pegged, as it should be! An IEM that can deliver the swagger, threat and excitement of this is doing it justice and the AKG does it justice, in my view. A particular favorite group of mine is the sound world of The Legendary Pink Dots. The combination of the Silverman's swirling keyboards and Edward Ka-Spel's wispy lyrics and vocals (inside joke) make for music that can take you to some less-visited places inside. The fact that I can be sitting on the train on the way home from work and still escape to the Dots' world is as good a recommendation as I can give.
 
Bottom line. Between AKG, Final Audio Design and various of the custom designers the IEM has been brought into higher levels of performance than ever before. Here in the States, one has to give credit to Ultimate Ears and JH Audio for pioneering the idea that custom IEM's can aspire to greatness and that audiophiles would respond to the performance by paying the price. And now we can thank AKG and Final Audio Design for believing that those of us who don't want customs would also pay for high performance.
 
Some will balk at the 5 star rating for value. The K3003 are indeed not cheap, but I know of no way currently to get equivalent performance in a universal IEM at a lesser price. To me, that's priceless.
 

When it comes to portable audio, it just doesn't get much more portable than an IEM and a Ipod/Zune/Sansa etc. Even tethered to one of the small battery-powered headphone amps, we are talking about something that fits in a coat pocket. And if, like me, you commute 2 - 3 hours a day, anything that amuses during this "dead time" is a good thing.
 
Recent years have seen an explosion of new IEM's upping the ante in sound quality (and price). So I bought a representitive sampling of units to see just what level of quality is attainable. The first round was between Westone 3, ER-4P and a Shure unit (whose number I forget). The Shure won this battle, but I wasn't really thrilled with any of them. Then the Shure broke...
 
So round two pitted the IE-8, CK-10 and eQ-7. I just couldn't get past the IE-8 quite ample mid bass and found the CK-10 good sounding but fiddly to use, so the eQ-7 became the phone of choice. It was good, but uninspiring. Still, a solid all-around performer. Then in a moment of insanity, I bought a pair of Final Audio 1601 SS. The FAD's threw everything into confusion. They were decidedly not uncolored with a subdued but expressive bass and a tres bumpy treble. But they showed the others the door dynamically, in terms of sound field and detail and in that hard to define sense of overall musical presentation. With all their flaws, they expressed the music in a way that made the rest sound so-so.
 
My thumbnail, unscientific, analysis was that there are certain things that tend to elude non-dynamic driver IEM's (except possibly the expensive and exotic units that employ large numbers of BA elements, which I have not heard). Being an audiophile, the FAD's areas of weaknesses still bugged me. The announcement of new FAD models was tempered by their employing BA drivers, but I had to give it a go. A pair of FI-BA-SB were ordered and actually did a decent job of bridging the gap with better dynamics and solidity than the other BA units, but a less idiosyncratic balance than the 1601's. Certainly a successful design, all things continued.
 
But hearing about the Sony EX-1000 with their large dynamic driver proved to be a temptation too strong to resist. Am I glad I didn't! The EX-1000 are not cheap, but they are still about 1/2 the price of the popular multiple BA customs, so not out of the question. They come nicely packed with a comprehensive assortment of tips, a shorter replacement cable and a nice leather carrying case. The magnesium driver housing is light but appears sturdy. There is a general sense of high quality and technology here with their 16mm drivers employing Neodymium magnets and Liquid Crystal Polymer Film diaphragms and their oxygen-free copper cables. I found them to be comfortable with the supplied ear-buds and easy to route for over ear cable routing. None of which assures the EX-1000 sonic worth, of course.
 
The first listening impression is of a vivid, clean sound. The bass, while not as strong as devoted "bass heads" may prefer, is noteworthy for it's sophistication and subjective lack of distortion. Treble is extended and generally smooth with an electrostatic-like clarity. Certainly it's not forgiving of bad recordings, but on the other hand, it doesn't invite bad recordings to sound worse than they are through uncontrolled treble resonances. The midrange is really excellent. Clean, yet lively and faithful to the unique texture and color of the individual instruments. The low level of self-noise and intermodulation products allows full detail to be available without being forcefully thrust at the listener. You can really hear this as Howard Hanson takes you through the instrumentation of his composition "Merry Mount" (The Composer and His Orchestra, Mercury). The extremes of dynamics here are also tracked quite well without much in the way of compression or information loss as things get busy. All this allows the impact and excitement of this music to come through to the listener.
 
Beethoven's Egmont Overture with Rene Leibowitz and The Royal Philharmonic Orchestra on an excellent Chesky release (originally a Kenneth Wilkenson recording) comes through both in it's quiet moments and it's riotous ending with it's natural timbres (mostly) intact. The sound-field is excellent for an IEM, second only to the aforementioned FAD 1610's. The news is also good with popular music. Lennon's "Strawberry Fields Forever" tricks and multitracks are there to be heard without fracturing the musical whole. Procol Harum's atmospheric "A Salty Dog" is very well served here as well. The percussive new age-y sound of Conrad Praetzel's "EnTrance" is evocative and enticing. For something a bit more hard edged, the vocal and guitar pyrotechnics of Iggy and the Stooges' "Funhouse" inspire excited air play-along (guitar, drum or vocal as you prefer), just as you would hope. Uh-huh!
 
Obviously, I like the EX-1000 (you think?). They are the best overall IEM's I have owned or heard (remember, I have no experience with the custom multi-BA units. Someday...) and aren't disgraced by the Sennheiser HD-800 or Sony CD-3000 (though they can't do some of the sound-field tricks of the large headphones). Few IEM's survive the comparison to good full-sized 'phones as well.
 
I used my Sansa Fuze, my Zune/iBasso combo and my home system with Dark Voice tube amp all to good effect. The better the signal fed, the better the results, but the EX-1000/Sansa Fuse system was very worthy for it's small size and the Sansa's cost effectiveness.
 
Now, if you are a confirmed bass-head or find any sense of sibilance anathema, these may not be the phones for you. But for me, while they are certainly not perfect (the treble could be smoother yet and the sound-field even more expansive, etc.) they are as good as I know in the here (hear?) and now in the non-custom multi-BA class. And I still think there is something to be said for large dynamic IEM drivers...
 
Kevin