These are the M4U TWM earbuds from PSB. PSB states “These earbuds feature advanced Magneto-Static technology and a Hybrid Planar dual-driver design for studio-quality sound in a compact form”. Bold statement…

Unboxing the buds for the first time, it’s a very lightweight and compact carry case, with some big & bold branding on the lid, USB C port to the rear and a single push button with 4 indicator lights to the front. Open the case up to find the buds, which include rubber tips and are sized/shaped to fill the outer area of your ear to provide a snug fit, which they do to a degree. The bud itself, the logo section is a physical push button, which is actually quite nice to have. None of this touch-sensitive stuff, you push the button in, you know it and so do the buds. The case has a satin black finish, with the buds following suit, although they include some gloss sections too. I like the look of the buds, I think they look quite smart. The case looks fine, it does its purpose. It’s worth mentioning in the box you get different-sized rubber tips and a USB cable for charging.

In terms of specification and features, they include a hybrid planar dual driver design, aptX adaptive Bluetooth, Audiodo and Roomfeel, both of which are pretty cool and I’ll touch on those later. Battery life is stated at 8 hours in the buds, 24 hours as well within the case. They’re IP65, so sweatproof and good for you gym goers. These can also be paired with the PSB app for various sound and EQ options. Price-wise, $199 right now.


As for performance, it’s fantastic and equally as enjoyable as the M4U 9 headphones I tried not too long ago. I listened to various tracks, different genres and they all sounded equally as good. Listening to some acoustic songs, the picking of the guitar, balanced with the strumming of another behind it, it was really good. When the bass drum came in, you could hear that little thud in the background and it sounded nice. So next I tried some old-school Kanye and classic UK garage. Punchy, vibrant bass but not overpowering in any way. The more I listened, the more I enjoyed using them. Out of the box these are really good.

That performance was based on the default settings provided when you first use the buds. However, there are options to tweak that sound, improve and personalise it to your needs. Personal sound via Audiodo, it’s a simple hearing test, where you’ll hear beeps from various frequencies and if you hear it, you tap yes, if not, you tap no and then a personal sound profile is created based on the results. This test is undertaken within the PSB app, it’s free and it’s certainly worth trying out. Now for me, as I tried the M4U9s recently, it retained my personal sound profile from before, so I turned that on and heard a difference straight away but it was a bit too crisp. This is obviously due to me taking the test with the headphones and not the buds, different components and fit etc. So i ran the test again, and this time it did sound less crisp and better than the original profile. So if youve got multiple PSB items, it might be worth having separate profiles for each device. 

Also available as an option, are four EQ’s. Roomfeel is the first EQ option which is PSB’s own sound profile. They’ve engineered this sound to emulate the experience of listening to high-quality speakers in a well-designed room, creating a natural sound. You’ve then also got Better Dialog, More Detailed and Tighter Bass. You can flick through them all and there are some subtle differences for me, I’d stick with personal sound and Roomfeel, which sounded the best in my opinion. The EQ’s look like they can be adjusted as you get shown the EQ sliders but you can’t, and you cannot create your own EQ either, yet. This feature may be added in the future. 


Personal sound and room feel on, gave an even better performance than the already fantastic performance. The more I use these, the more I love them and quite frankly, won’t go elsewhere, unless I’m exercising. PSB are smashing it right now.

That leads me to comfort. They are comfortable, they fit well and the rubber tip helps keep them in place but for some reason, the right bud wasn’t as secure as the left and when cycling did cause some problems with adjusting and almost falling out, which isn’t ideal. I changed the size of the rubber tip but it didn’t really help, unfortunately. A shame for some maybe but for me, a quick indoor cycle, I can use something else. You may have a different experience than me and maybe so snug that they’ll never fall out. 

The controls work well, are very easy to use via the push button and you can control tracks, volume and calls. The microphone quality is good, I took a few phone calls and had a Zoom call with these and had no complaints on either end. Battery life is good, I’ve racked up over 40 hours I’d say so have charged the buds multiple times, the case too. 8 hours in the buds is accurate and more than enough in my opinion. 

ANC or active noise cancellation, notice I haven’t talked about that yet and that’s because these don’t include it, but you wouldn’t know. Due to the shape and fit of the buds, along with the features included, they do a great job of filtering out external sounds anyway, equally as well as earbuds that do include noise cancellation. You’d expect it to be included at this price point but they perform so well, you wouldn’t necessarily notice you don’t have it, unless you are on an aeroplane or similar. 

So there we have it, they were the M4U TWM earbuds from PSB. Near on perfect in my opinion and highly likely my new day-to-day buds. Outstanding performance, good battery life, look good, they’re comfortable and they’re easy to control. I think the retail price of £199 here in the UK is fair for the performance you’re getting. I don’t think I’d change anything, I only wish the right bud would sit better in my ear. 

For more info and to purchase, head over to the official PSB website.