From the outside, the S150 looks like a carbon copy of its sibling, the Award-winning Airstream S200.
There’s no difference in size and the finish options (black or white) are the same.
MORE: Monitor Audio Airstream S200 review
The drive units and internal amplification are all virtually identical too. There’s a 20mm tweeter flanked by two 7.5cm mid/bass drivers behind the fabric-covered grille. They sit on an angled baffle to help disperse sound.
The volume rocker button is in the same place, on the right-hand side of the speaker, as are the input selector buttons.
The LED on the front still shines cyan when you’re using Bluetooth and green when you’re wired through the 3.5mm input.
And yet, the S150 is £50 cheaper than its stablemate. So what’s the catch? The S200 was blessed with features such as AirPlay and DLNA streaming, but both of these have been stripped out of the S150, leaving you with just Bluetooth (the better quality aptX, mind you) for your streaming fix.
The USB input on the rear has made the crossover, but purely for charging Android and iOS devices. The S200 allowed you to play Apple devices through the socket, but that’s a no-no on the S150.
So, a feature cull is one difference. The second is slightly subtler: the power supply for the S150 has been tidied up by merging it with the plug into one unit, as opposed to being a separate block. It’s a slightly neater solution.
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So what does this all mean for sound quality? Has stripping out features robbed the Monitor Audio of some of its musicality? Quite the opposite.
The S150 sounds more robust and confident. You still get lavished with the same impressive clarity and openness provided by the S200, but music is delivered with extra solidity and conviction.
Play Jamie T’s Sticks ‘n’ Stones through Spotify and the track flies along at speed. The drum kit sounds punchy and precise, and when the riff of the bass guitar kicks in, it ducks and weaves in perfect harmony.
At high volumes, the S150 remains composed and well behaved throughout the frequencies. You should have no trouble filling small- to medium-sized rooms.
By the same token, the speaker works equally well at low volumes. It still picks out loads of detail and manages to communicate dynamic shifts, even when you’re using it for background listening.
MORE: Spotify review
Switch pace from Jamie T to the lazier rhythms of Major Lazor’s Lean On, and the Monitor Audio adjusts accordingly. The track doesn’t lose momentum, though. Percussion still sounds agile and lively and the vocals sit in plenty of space, but don’t feel detached as the rest of the track unfolds around them.
Shift down another gear with Birdy’s acoustic track Wings, and we’re expecting the S150 to succumb to the demands placed on its tweeter. But the speaker handles the sparkling highs confidently.
There’s no harshness or brightness to speak of, but neither does it sound safe or rolled-off. This balance is no mean feat in a budget wireless speaker.
Switch to a wired connection via the 3.5mm jack and the sound becomes a bit fuller and more refined. Of course, you lose the convenience of Bluetooth, but it’s worth trying to see which you prefer.
If you can live without some of the extra features provided by its more expensive sibling, you’d be crazy not to audition the S150.
It’s more affordable and, in our opinion, sounds even better. You’re looking at a real contender for class-leading status.
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