Personal Favourites (Updated)
I've been asked quite a number of times as to what I liked best. Thought I'd throw down some IEMs that I enjoy a fair bit. Keep in mind that this is my personal opinion and this list can and will change over time. Some of the factors that help evaluate are "timbre", "tonal balance", "transient response/clarity" and "technicalities". The order is not a ranking.
1. Sony IER-M9
For me, the IER-M9 proves itself to be the king of imaging. The M9's strongest asset is how it handles spatial cues - it's able to correctly portray a sense of a "3D" soundstage where I can accurately tell and gauge the distance between instruments. In addition, the M9 has a great deal of balance in its frequency response. I don't feel that any set of frequencies overwhelm each other. The music sounds very balanced and I hear everything. It also has great extension on both ends - providing deep subbass rumble and very well extended highs. Notes are always well separated from each other and the M9 simply refuses to congest no matter what tracks are thrown at it.
The biggest weakness of the M9 would be its slight lack of dynamics. I wouldn't go as far as to say it sounds dead or like a wall of sound. I think it's just that the lower treble is very much tamed which leads it to sound more relaxed. Personally its never sharp, harsh or sibilant. I would even go as far as to say that the M9's transients are a tad blunted, especially with its woofers.
A problem I find with the M9's woofer is that it sounds "slow" next to a typical BA bass setup. The woofer does not sound traditionally BA and instead has a more bodied decay. However the attack is a bit flabby/bloomy which makes the woofer sound a bit lazy and slow sounding. Outside of that, the M9 naturally lands in my list as the strongest contender with spatial cues and soundstage.
2. Etymotic ER2 Series
When the brand "Etymotic" is mentioned, some would associate the brand with terms such as "clinical" and "sterile". I personally think this holds true for the ER3 and ER4 series. The tuning on the 3 and 4 lacks warmth and exhibit what I refer to as "BA timbre". I find that BA lacks that natural body and decay of DDs and instead can sound grainier and leaner. However when it comes to the ER2, I think that Etymotic has done a great job to change this preconception. The DDs used in the ER2 have a very smooth and pleasing response, as if it was rid of any peaks. The ER2 has a much more natural timbre (and tone) to my ears with its elevated bass response and depth in the sound.
I've had chats and discussions with some audio friends of mine regarding what defines resolution. Some claim that ER4 still offers better "resolution" over the smoother ER2. Some say that the grain in the ER3/4 is texture and is what defines resolution. Yada yada. For me, the ER2 is able to reproduce transients as clean, if not cleaner than the ER4. It does so in a smooth, very natural way. Take for example, the resonance in the low keys of the piano. The ER2 presents those lines/resonances in a bodied expression whereas ER4 has greater emphasis on the initial attack. Which type of presentation is better is up to the individual to decide. I think resolution is quite an all-encompassing term. It's a mixture of factors such as transient response and timbre imo.
If not, the ER2 is not as bright in the 8-10k region which makes it a more relaxing and laid back listen. Makes the ER4 sound a bit peaky, heh. I do also feel that ER2 extends much better in the mid to upper treble region where it does cymbal decay very nicely. I do think that if the ER2 had more brightness in the 8-10k region like the ER4, it would be a very very good curve.
Last point about the ER2 is that the driver packs some serious speed. It doesn't sound congested despite the typical "etymotic soundstage". Everything layers properly as it should. I think it's the fastest DD I've heard to date in an IEM. Overall, just a very good IEM. XR or SE...I think I would suggest most to spring for SE as XR can be a bit too dark sounding with its bass boost. SE has better overall balance but XR's clean subbass lift helps the bass to roar.
I do think it can be a bit ridiculous to put the ER2 next to all the top dogs - but hey this is just a list of personal favourites. The ER2 excels in the areas it is supposed to. Which is why I like it.
3. qdc 8SL/Gemini
The reason why I didn't include the Anole VX is because the VX has a further lift in the lower-mid treble region which makes it a bit harsh and aggressive to listen to in an extended period of time. 8SL/Gemini strikes a better balance in the FR for me. Both of them offer a great soundstage, fantastic level of separation/layering, cleanly reproduced transients free of smearing and great extension on both ends. The 8SH has a further lift in the 1-2k region but I find that this lift made vocals a bit too shrill and unnatural sounding since 8SH's vocals are not as warm too. If not, the 8SL/Gemini sports decent bass - has the speed and attack to make it an engaging listen.
However in certain tracks, the bass of the 8SL/Gemini can sound a tad hollow and "BA-like". If not I feel that the both are very well tuned with solid technicalities and decent enough tonal balance.
4. Shure KSE1200/1500
A friend once shared an analogy with me - "hearing the KSE is like putting on your glasses in the morning". I think this holds true. The KSE is a detail monster - it sounds like 4K resolution where you're coming from 1080p. It's just so damn clear (PLEASE USE FOAM TIPS btw). It captures every resonance, every naunce in the track. It's cliche to say, but I do hear things I've never heard before with the KSE. The resolution and detail it provides is simply outstanding and sits at the very top in that category. Add that with it's crazy speed and it also never congests. Just so damn fast. It does have a small-ish soundstage but it won't matter because the music is flashing past by in HD.
The KSE's weakness would be it's tonal balance. Has this peak at 2k which makes vocals sound a bit unnatural. It does put electric guitars forward in the mix though. Other than that, I find the bass well extended (if it isn't well extended then the fit is definitely a bit off) and has a lift to provide some warmth. Treble has that great sizzling decay with immense speed and clarity.
5. InEar Prophile 8
Sterile and clinical sounding. Some say it lacks dynamics but imo its fine in that aspect. The PP8 is one of those IEMs that does spatial cues and imaging well. Just sounds boring due to its lack of warmth in its tonal tonal balance. Another weakness would be its lack of treble extension in the top end. If not, the entire FR is well balanced like the M9.
6. FiR M3 Universal
Perhaps the biggest "?" in this list. I say so halfheartedly because I have no idea if the customs will end up sounding remotely like the Universal. The universal has a very straightforward, bass boosted + neutral type of signature with a good emphasis on tonal accuracy in the midrange. Treble is well extended, reminding me a bit of the cymbal decay in the M9. Lower treble is perhaps a bit dipped to prevent fatigue.
Why I also label it as a "?" is because I think it can sound great if the amount of bass is toned down. One of the problems with FiR's DD is that I find the size of the image of the bass is much bigger than the mid and highs. If FiR can tone down on the bass and focus on improving the tightness in the DD, I would love this a lot.
