Introduction

Westone Audio is a pioneer in the in-ear monitors market, having worked on both universal- and custom-fit IEMs for over four decades now. The brand has especially made a name for itself when it comes to live performers on stage and shows using Westone IEMs which then led to their fans and other up-and-coming musicians deciding to follow suit. Westone tends to use balanced armature drivers across its product line as evident by our coverage of its recently launched MACH series which comprised of eight IEMs walking a thin line between consumer and professional use. With the newer AM Pro X series though there's no confusion given these are directly targeting performers and recording artists. That's why I have deliberately added professional in the title of this article so people are not confused about the intended market.


Unlike the MACH series, Westone has only three entries in the AM Pro X lineup—AM Pro X10, AM Pro X20, and AM Pro X30. These are differentiated by the number of balanced armature drivers inside with the most expensive AM Pro X30 using three BA drivers. This also happens to be the subject of today's quick look and the preview photo above confirms the use of a similar shell that was on the MACH series, which promises to be extremely comfortable in use. What makes this a professional set is a feature Westone calls the passive StageSense filter system which can be thought of as analogous to ambient mode in a Bluetooth wireless set. Essentially, this deliberately feeds in some of the external sound to the ear canal so you can be aware of environmental cues, take a break when no music is being played but still be able to listen to others around etc. Westone says this feature has been extremely popular with its traditional users and sees potential in a "work from home" environment for a whole new customer base too. Thanks to Westone, via Hifiheadphones in the UK, for providing a review sample to TechPowerUp, as we begin our coverage with a look at the product specifications in the table below.

Packaging and Accessories

Westone goes for a simple packaging design on the AM Pro X30 with the brand logo and product name on the front along with a large render of the IEMs showing off how they look with the StageSense filter system integrated. The driver setup as well as other salient features are also seen here and on the back where product specs make a showing too. I also appreciated the list of items inside so you know exactly what to expect. The outer sleeve slides off to reveal a white inner cardboard box adorned with more Westone logos. This box opens from the bottom and we see a thick foam sheet protecting not only the IEMs in their individual compartments but also the carry/storage case. Underneath is paperwork including a user manual as well as a branded cleaning cloth.


The carry/storage case is the exact same as on the less expensive MACH series of Westone IEMs and what it calls the "Mini Monitor Vault II." This is a custom designed crush-proof and watertight hard case in a translucent red color and the plastic construction feels sturdy enough. The smaller size makes this case easier to travel with and it retains the water- and air-proof design too with O-rings and a pressure-relief built into it. The inside is lined to help prevent scratches to the IEMs and the cable, and the various ear tips were found inside here along with a cleaning brush. Westone provides five sets each of silicone and foam tips—the fifth silicone set is pre-installed on the IEMs—that are relatively long compared to what you usually find on IEMs and seem intended for a deeper seal in the ear canals. The equivalent sized silicone and foam tips have the same bore color to them, so we now know the black bore silicone tips are the ones that come already installed.


The AM Pro X30 IEMs ship pre-assembled with the cable and one set of ear tips as previously seen, thus making it easy to get going straight away. A closer examination of everything individually necessitates separating them which is simple enough given Westone uses the excellent Estron T2 connectors here. This is a lower profile and stronger push-fit style connection similar to the more common MMCX and you simply pull out the cable on each side with a steady force.

Closer Look

The cable that ships with the Westone AM Pro X30 is the Linum G2 SuperBaX which costs ~$150 by itself. This starts with a right-angled 3.5 mm TRS single-ended connector from your sources and uses 168 strands of silver-plated copper conductor in a quad-twist configuration. The cable is non-microphonic and is longer than usual to further facilitate use on stage or in recording rooms where the source might be further away. There is Westone-branded plastic hardware for the divider and cable cinch following which we see pre-formed ear hooks which are unfortunately not great to work with. These are too stiff and will likely necessitate some shaping under pressure to properly fit around your ears and remain in place, unlike how they may end up being out of the box. We then find the aforementioned Estron T2 connector plugs which are quick-disconnect connectors that also come gold plated for oxidation resistance as does the 3.5 mm connector. These plugs are rated for 10,000 insertions minimum and are designed to be easily inserted and removed with IP67 dust and spill resistance. There are color-coordinated rings and markings on the housings to help indicate the left (black) and right (red) channels.


The Westone AM Pro X Series follows the trend of other Westone IEMs in being designed for long and comfortable use, hence the trademark Westone horizontal oval shape that is tiny and tucks in easily inside the concha. We have a clear resin shell this time compared to the opaque plastic on the MACH series and the AM Pro X30 has a green insert as part of the StageSense filter system to help differentiate it from the AM Pro X10 (red) and AM Pro X20 (blue) visually. There's no bling here as with most recently launched consumer IEMs, with the face plate effectively being the Westone branding on the opening that is part of the StageSense feature allowing some ambient sound through the green colored insert into the ear canal. This is different from the actual drivers which you can see through the transparent shell and also feeds into the ears. There is a filter on the top to prevent contaminants entering the opening there with the actual nozzle being long and thin for a deeper fit. There are L/R markings on the inside to help identify the left and right channels, respectively.


Fitting the different ear tips is simple enough given the nozzle is on the thinner side, and so you can slide the ear tip bore over the nozzle without much struggle. At the same time, these specific tips were chosen for the AM Pro X Series to where they are not loose and give you a few different options when it comes to not only the flange size but also the flange length and ear tip material itself. Seen above is the pre-installed silicone tip and a foam tip, all in size M presumably, to give you a better idea of how they look on these IEMs. Keep in mind that both ear canals don't need to have the best seal with the same size or set, so try the different options provided since third-party tips may not work out as well for this more unusual design. Regardless of which tips you pick, the next step is to re-connect the cable by carefully identifying the matching channels and orienting the cable around your ears.

Fit and Audio Performance

Here we see the right channel of the Westone AM Pro X30 installed in an anthropomorphic pinna with the pre-installed silicone ear tip used. I have average-sized ears, and the ear mold above represents my own experiences well enough as a proxy. Size M silicone tips are my go-to for testing, since foam tips are not included by some brands. The Linum SuperBaX is the most frustrating part here as the pre-formed ear hooks can be annoying to re-shape and keep in place around the ears. You may well need to have the cable cinch secure the cable in place in use for a while before it starts to retain memory. I also wish Westone had gone with angled housings on the cable to allow for a more natural positioning behind the ears though. On the other hand, the IEMs themselves are easily among the most comfortable earphones I have ever used and this includes CIEMs molded to my ears. Westone is leveraging its decades of experience here in producing a tested design which fits sideways to fit most users and there is some wiggle room too. Those with narrower ears may still want to test this first but overall I'll give Westone the benefit of the doubt when it comes to securing a comfortable and isolating fit with these UIEMs. The all-resin build also helps keep things light and they seem sturdy enough to handle daily wear and tear too. As for the drivers inside, Westone does not provide any information about the actual units aside from saying the three balanced armatures used here are in a 3-way passive cross-over. This means one each of the drivers handles the lows, mids, and highs with the larger subwoofer no doubt catering to the bass. The AM Pro X30, as expected of pro IEMs, has a relatively higher impedance of 56 Ω for better signal-to-noise ratio from clean sources and yet remains extremely easy to drive given the rated sensitivity of 124 dB/mW—you will be fine with a decent dongle itself, let alone a more powerful portable DAC/amp.


Testing was done similar to all other IEMs, such as the Westone MACH series. Seen above is the measured frequency response for both channels of the AM Pro X30 plotted against my preference target and can be inspected further here. Note that the tuning of IEMs doesn't have to actually match my target as much as that being there to indicate what I personally like. As long as the tonality makes sense and is well-executed, I can certainly appreciate something trying different from the norm. This is also why I have a compensated average frequency response relative to a less subjective target wherein deviations from this are also easier to see. First up, we see an excellent channel balance between the two sides of this set. Keeping in mind that this is a randomly picked review sample, this is good to see and yet expected from a product targeting professionals foremost. Next, and this is where things get interesting, we see Westone is going for a warm-neutral sound—or at least trying to anyway.

I will admit that I am not necessarily part of the target audience here but it does seem clear that the pro market for IEMs has been stubborn in tuning for years now. The consumer side has seen so much growth that you can now get differently tuned IEMs to appeal to various preferences without paying a lot for it. The pro side, on the other hand, seems content to try and give a flat line and let you fill the blanks. This can work well when the baseline works well enough and the set is extremely receptive to EQ. But it can also be seen as someone just content in using its brand name to put out more gear that quite frankly doesn't sound very good at all even with the caveat of professionals not necessarily caring about detail retrieval, sound stage etc. The AM Pro X30 is a slightly bloated mess which feels allergic to upper mids resulting in a poor user experience out of the box. I had to cut down the lower mids, add in a bass shelf, add some actual ear gain so vocals and instruments don't feel as if they are being played through a pillow, and then add in some treble too. At this point I might as well have purchased something else which is already closer to putting out sound that feels accurate and actually neutral, if not even enjoyable. The consolation here is this isn't hard to do and the drivers clearly can handle it, but I have to say that if you are a professional trying to use these for stage performance then you should do all this beforehand to be ready. Better yet, look at other IEMs first and make sure the Westone AM Pro X30 is what you want in the first place.

In fact, the one selling point here is the StageSense filter system. You get, despite an excellent fit and seal, a deliberately reduced level of isolation. Westone claims ~10 dB of passive noise cancellation here compared to ~20-25 dB that you can expect from a similarly well-fitted set of wired IEMs. This means you will be able to hear, albeit quieter, your surroundings while still wearing these IEMs in the ear. You don't have to take them off between shorter jamming sessions thus and there is added comfort to help further by preventing pressure build-up in the ears. On stage you can listen to cues from your audience or band members, for example, whereas the feature can be handy in recording studios for various reasons. Likewise, I can see this being handy in a shared office space or any scenario where you'd use ambient modes in a TWS or over-ear wireless set of headphones where you simply need to have some sort of environmental awareness. I can also see this doing double duty as a set of fancy ear plugs at concerts! Perhaps then the best thing to do would be to get the least expensive AM Pro X10 and call it a day if you simply want this feature.

I was in half a mind to write up a comparison section too but really there's not much reason to do that. Westone's MACH 30 with its three balanced armature drivers is arguably even easier to fill out via EQ but sounds even worse out of the box. It also misses out on the StageSense filter system and costs more too. I also don't have any other pro IEMs here necessarily, although there are plenty of monitoring IEMs covered before which generally do a better job for mixing and mastering. If you simply want a well-tuned set, you can find them for under $20 these days to where the AM Pro X30 is a hard sell given it costs $480 from the Westone online store in the USA but is somehow discounted in a few other regions such as the UK where it can be had for £307 (inc. VAT) from Westone or Hifiheadphones. It's a much better buy outside the USA as of the time of this article thus and yet the point remains that these are not for everyone. I can only urge anyone remotely interested in these to demo them for a few days before committing to a purchase.