I usually have eartips selection section right after Sound Analysis, but in this review decided to move this section upfront as a preamble to Sound Analysis. According to Westone, the tuning of MACH series was adapted from their CIEM (ES series) counterparts, and I found this to be reflected in eartips selection since these new IEMs sound better to my ears when used with foam eartips rather than silicon. Foam eartips provide a custom-like seal with a more natural sound and better isolation. Contrary to that, silicone eartips attenuate down the bass and made lower treble a bit peaky, even sibilant in some models.
The selection of eartips is crucial to any universal in-ear monitor and will affect the sound, especially the bass impact depending on the seal. Due to a large opening of my earcanals, I usually go for the largest size eartips to get a better seal. Here, I end up using medium size “gray” foam eartips for a deeper insertion and better seal. Also, as already mentioned, some other eartips manufacturers are starting to offer either 2mm bore eartips or to include 2mm spacers for use as an adapter for 2mm nozzles to fit regular eartips.
I analyzed MACH series models sound performance paired up with LPGT DAP while playing a variety of test tracks, such as Agnes Obel “The curse”, Sandro Cavazza “So much better” (Avicii remix), C-Bool “Never go away”, Ed Sheeran “Shape of you”, Alan Walker “Darkside”, Galantis “Hunter”, Iggy Azalea “Black widow”, Indila “Boite en argent”, Dua Lipa “Love again”, Counting Crows “Big yellow taxi”, Bob Marley “Jamming”, David Elias “Vision of her”, and Michael Jackson “Dirty Diana”.
Please keep in mind, all sound impressions were done using Westone foam eartips, medium (gray) size, and corresponding stock Linum cables. Also, just as a general comment, the sound tuning is not as forgiving, poor recording will be like under microscope with every fault visible.
This model has a flat tuning with a natural tonality and clear retrieval of details. Bass tuning is very neutral, still packs a nice punch, just lacks sub-bass extension thus not as much weight. Mids/vocals are clear and detailed, not too revealing, but very natural, and more forward in presentation. Treble is clear, detailed, and natural as well. Not too airy or crisp but has a good definition and plenty of clarity. The sound is not as layered or separated, but the level of clarity and detail retrieval is rather good for those who enjoy non-fatigue flat sound without the need to analyze micro details. This tuning might work for both musicians and sound engineers. Soundstage is wide open.
Probably my 3rd favorite tuning, nicely balanced signature with a little more emphasis on clear detailed mids. Bass is closer to neutral, but still has a good extension down to sub-bass level and tight articulate punch, just the overall quantity is a bit north of neutral. Mids/vocals are more forward, and sound clear and natural. Treble is also well extended, clear, and detailed. Technically, I find 20 to be actually closer to upper end models, not exactly the same level of resolution or layering, but not too far off either. It sounds great and will be perfect for musicians who value vocal performance and need accurate low-end punch, maybe even for some sound engineering for checking mixes. Soundstage is surprisingly wide, and imaging is great too.
The tuning is more energetic and revealing, with a balanced signature that pushes a little more toward being mid-forward. Bass is just a bit north of neutral, has a nice subtle lift, mids/vocals are clear and brighter in tonality, especially upper mids. The only problem is a bit over-exaggerated lower treble which makes the sound sibilant, resulting in upper frequencies being brittle and plasticky. Foam eartips smooth it out, so it helps. The resolution of the sound does take a step back in comparison to higher models, but the big problem here is a lower treble spike that affects the tuning. Soundstage is wide open.
This is my least favorite tuning due to mids being attenuated, making vocals muffled and even a bit muddy. The overall tonality is warm and organic, bass is elevated with more mid-bass punch, lower mids are thicker and upper mids are scooped out which affects the clarity of the vocals, making them boxy and muffled. Treble is also attenuated down which reduces upper frequencies extension and airiness. This tuning could have worked as V-shaped if treble would be more elevated. Instead, these sound more congested, vocals are muffled, and treble has poor definition. Soundstage has intimate width/depth, making the sound more closed in.
The tuning of 50 feels like it was derived from 60 rather than bassier 70. I do hear a balanced sound sig with a smooth natural tonality. Bass has a perception of digging in a little deeper and having a bit more weight than 60, but the biggest difference here is the reduction in treble, reduced peaks of lower treble and mid-treble. As a result, mids sound smoother, more organic, but at the same time also lose some of the resolution in favor of warmer tonality, making its tuning suited for those who are looking for IEMs with a more forgiving tuning. Not sure if this is suited for musicians or audiophiles, but general consumers might enjoy it. Soundstage has more depth than width.