Sound analysis.

I usually subject everything to a burn in, regardless if it’s a pair of headphones/iems or a DAP or a DAC. Here, with a dynamic driver and multiple crossover components, I put W900 through 150 hours of burn in to collect my initial sound impression. In the last few months, I probably put another 100hrs of listening time, but haven’t noticed too much of a drastic change beyond the initial burn in. Also, please keep in mind, the sound analysis was done using a stock NA cable which gives W900 a little smoother and less revealing sound characteristic.

I find W900 to have a balanced and a resolving signature with a neutral-smooth and very natural tonality. Before burn in I felt bass was a lot more enhanced, and it took close to 100hrs for it to calm down, though impact is still noticeable. What stands out for me here is the accuracy of the timbre, especially with non-synthesized acoustic instruments where the quality and the quantity of low end plays an important role. It’s not the most analytical or with the highest level of detail retrieval IEM, but it’s among the top neutral-smooth IEMs I have tested when it comes to resolution. Also, despite a hybrid 9way design, it’s still a very coherently-tuned IEM, thanks to it’s TruXross 4way crossover where I don’t hear overlaps or disjoint gaps across FR.

Starting with a bass, it has a very good low end extension, with a textured sub-bass rumble that doesn’t overwhelm but has enough weight to build a solid foundation under an articulate mid-bass punch. The impact of the punch is a little elevated but not to the point where it would push the signature into L-shaped territory. The punch will cut through the mix, but it will not destruct you from paying attention to other parts of FR. The bass is well controlled, no spillage into lower mids, and typical of dynamic driver it’s not too fast or too slow, with a medium speed attack and slightly relaxed decay.

Lower mids are neutral and very clean, they add to the body of the sound without coloring it. Upper mids are very resolving, neutral, natural, smooth, and with a perfect balance without any bright or warm coloring. Both male and female vocals sound very natural. Also, the mids level is nicely balanced with lows and highs.

Treble is also rather neutral, but at the same time detailed and with an extension beyond the horizon, like it has no boundaries. There is some airiness and just enough of crunch to give it good definition, but both airiness and crunch are in a very moderate dose, which gives treble extension a very natural tonality.

W900 has lots of clarity and details, but not as much airiness which also reflects in sound being not very layered or having an extreme separation. It’s clear and detailed at the top but also smooth and natural, not congested, just lacking the airiness layer between the sounds. It does improve when you start switching cables, especially with 1960 4wire which noticeably improves technical performance of W900. It’s a rather expensive cable, but has the best pair up with W900. For other cable recommendations, please refer to the Cable section of the review.

Soundstage is very wide, and with above average depth which puts you in front of the stage, being not too close or too far out, just wrapping around you. To my pleasant surprise, soundstage held its width even with some of my lower res sources.

Soundstage width helps a lot with imaging and positioning where you have a convincing placement of instruments and vocals, and relatively accurate positioning of all the sounds. Neutral tuning sometimes can make sound a little congested where it’s hard to pin-point every instrument, but it wasn’t the case with W900.

I found the source variation to have a small impact on the sound quality of W900. When you are dealing with a more revealing analytical IEM tuning it could affect source pair up, but with a more neutral tuning and balanced resolving signature, W900 was not as picky which means that you can enjoy high resolution sound even from your smartphone.

Comparison.

Comparison was done using W900 with a stock SPC cable. Other IEM cables are noted below. DX200 w/AMP1 was used as a source, only 3.5mm HO, and I also used adapter for IEMs with balanced terminated cables. In every comparison, I volume matched iems by ear.

W900 vs Vega (spc litz) – both have a very similar expanded soundstage width/depth. Sub-bass extension and rumble is also very similar, though a little less intense in W900. Mid-bass punch is stronger in Vega. Lower mids in W900 are a little more neutral, while Vega has a bit fuller body. Upper mids is where you starting to hear more difference where W900 is more natural, smoother, organic, while Vega is brighter and a little harsher in comparison. The same goes for treble, W900 treble is smoother, extends further, while Vega’s treble is brighter and crisper in comparison. Due to these differences, W900 sounds more balanced and smoother in comparison.

W900 vs U12 w/M15 (ref8) – both have a very similar soundstage width, but W900 has more depth. Mid-bass punch is very similar between these as well, but W900 has a deeper sub-bass extension with more rumble. Lower mids are quite similar, with fuller neutral body, and the same goes for upper mids being smooth, organic, resolving, but not as revealing. The only difference, due to soundstage depth, W900 vocals are a little more out of your head while U12 vocals sound closer and more intimate. Treble is close as well, but W900 has more sparkle and better extension.

W900 vs SEM9 (thor ii+) – W900 soundstage is a little wider, while both have the same depth. Also, W900 has deeper and higher quantity sub-bass rumble and stronger mid-bass punch. Lower mids are nearly identical and so does the upper mids, a strikingly similar tonality, though W900 is a touch smoother. The same with a treble, very similar sparkle and definition, even extension, but W900 is just a little smoother. Keep in mind, I’m testing W900 with its stock spc cable vs SEM9 with pure silver Thor II+, but in this comparison the difference is only down to the bass.

W900 vs W80 (ref8) – W900 soundstage is a little wider, while both have the same depth. With bass, W900 sub-bass is deeper and has more rumble, while both have a very similar mid-bass punch. Also, lower mids are quite similar as well, but W80 mids are a little smoother and a touch warmer while W900 is more neutral and more resolving. With treble, W900 has more sparkle and slightly better extension, while W80 is a little smoother, though both have a similar definition.

W900 vs Andromeda (spc litz) – both have a very similar expanded soundstage width/depth, maybe with Andro having a touch more depth. Also, sub-bass rumble is quite similar, though mid-bass punch is a little stronger in W900. Andro’s lower mids are a little leaner while W900 is more neutral, and upper mids in W900 are smoother, more organic, while Andro is brighter, more upfront, and a harsher in comparison. Anro’s treble is also brighter and crisper while W900 is smoother and more even.

W900 vs K10UA (spc) – W900 soundstage is a little wider, while depth is the same. W900 has a deeper sub-bass extension with a little more rumble, and a stronger mid-bass punch, while K10UA bass is a little too polite in comparison. K10UA lower mids are leaner while W900 has more body in comparison. Upper mids is where you will find the most polarizing difference will W900 being smoother and more organic, while K10UA upper mids being more upfront, a lot brighter and more analytical and a bit harsher in comparison. K10UA treble is also crisper and more revealing, while W900 is smoother and more extended.

W900 vs UERR (ofc cable) – W900 soundstage is a little wider, while depth is very similar. W900 sub-bass goes deeper and mid-bass has more impact, and overall bass has more quantity in comparison to a more neutral UERR. UERR lower mids are a little thinner and upper mids are a little brighter while W900 upper mids sound a little warmer and more organic in comparison. W900 treble is smoother and more extended, while UERR is crisper and with more sparkle.

W900 vs Zeus XRA (1960 2wire) – Both have a very similar width, with Zeus having a little more depth. Zeus bass is very neutral, so in comparison W900 will have noticeable more sub-bass and mid-bass. Also, Zeus lower mids are a lot more neutral in comparison to a fuller body W900, and W900 upper mids are smoother and more organic in comparison to more resolving Zeus upper mids. With treble, Zeus has more sparkle and airiness, but W900 is more neutral and feels more extended.

W900 vs A91 Sirius (stock SPC) – W900 soundstage is a little wider, while both have a similar depth. W900 goes deeper with more sub-bass rumble, where in comparison A91 sounds a lot leaner. The same with mid-bass, W900 has a little more impact. A91 lower mids are more neutral while W900 has more body, and upper mids are a little brighter and slightly leaner in A91 where in comparison the upper mids of W900 have more body and more organic, and have a little better retrieval of details. Also, W900 treble has more sparkles and better extension.

Pair up.

Here is how W900 w/stock cable pairs up with different sources.

DX200 – very spacious sound, great soundstage expansion; smooth detailed tonality with a deep sub-bass rumble, well controlled tight mid-bass punch, smooth resolving organic mids, well defined extended treble.

LPG – excellent soundstage expansion, in both width and depth; smooth detailed tonality, a little more revealing, deep sub-bass rumble, powerful mid-bass punch, a little stronger than DX200, smooth resolving natural mids, a little more layered in comparison to DX200, well defined extended treble.

Opus#2 – very spacious sound, great soundstage expansion, smooth detailed tonality, deep sub-bass rumble, well controlled tight mid-bass punch, smooth resolving organic mids, excellent treble extension. I heard some similarities here in comparison to DX200 pair up, but I felt that upper mids in #2 were a little more forward.

X7 w/AM3 – spacious expanded sound, a little more revealing tonality with a softer bass, but you still get a deep sub-bass extension, and a nice mid-bass punch, though not as strong. Mids are a little brighter and slightly thinner. Treble is crisp and extended.

X5iii – very spacious sound, great expansion in both width/depth. Deep sub-bass rumble with a nice mid- bass punch. Mids are smooth, detailed, natural, slightly more forward. Treble is well defined, clear, and with a nice extension.

i5 – very spacious sound, great soundstage expansion. Deep sub-bass rumble with a nice tight mid-bass punch. Mids are smooth, detailed, layered, a little more revealing and slightly more forward. Treble is well defined, clear, extended.

AK120ii – great soundstage expansion, smooth detailed tonality; sub-bass goes deep but has a touch less rumble in comparison to other DAPs, and mid-bass punch is a little softer. Mids are smooth and detailed, not super resolving, and treble is well defined and with great extension.

Plenue M2 – very spacious expanded soundstage, deep sub-bass rumble, decent mid-bass impact, smooth detailed mids, well defined and extended treble. I was surprised how well it paired up without a help from JetEffects.

Note 4 – nice expanded soundstage, for sure above the average width/depth; deep sub-bass extension and nice rumble, punchy mid-bass, smooth detailed natural mids, well defined extended treble. Surprisingly good pair up with my smartphone, though not on the same level of resolution as other portable DAPs.

Overall, it paired up great with every source.

Conclusion.

With so many IEMs I have access to for review and comparison purposes, it’s physically impossible to dedicate time to all of them since I don’t spend hours every day listening to music. But I do have a handful of favorites in my constant rotation and W900 made the list from day one! As a matter of fact, I spent so much time featuring them in all my reviews while testing with other sources or comparing to other iems, that it felt like I have already reviewed W900. Not an excuse, but I’m glad I was finally able to finish the review and now can share it with all my readers.

AAW was always leading the way with flagship hybrid designs, and this 9-way hybrid is no exception. But it’s not just about throwing in together a bunch of drivers and calling it a flagship hybrid. AAW crafted a design with a very coherent sound tuning, delivering an accurate (to my ears) and a natural timbre of instruments, very smooth, very resolving, and with a great extension in both lower and upper regions of FR. If you are looking for a flagship IEM with more bass impact or with more analytical sound, there are other choices out there to suite your needs. But if you want a balanced tuned IEM with a resolving signature, expanded soundstage, great isolation, easy pair up with different sources, and a neutral-smooth natural tonality – W900 fits the bill just right!