Supports a wide range of streaming services and hi-res formats
Portable with optional battery
No DLNA/uPnP support
Clunky network sharing
Lacks the muscle and width of larger models
Review Price: £299.00
1GHz ARM Cortex A9 multi-core processor
2 x 20W digital amplifier
3.5-inch woofer and 1-inch tweeter
BluOS multiroom controller app with Spotify, TIDAL, Napster, Qobuz, Deezer
Hi-res MQA, FLAC, WAV, AIFF and ALAC playback up to 192kHz/24-bit
Optional battery pack offers six hours of portable playback
What is the Bluesound Pulse Flex?
Pulse Flex is the smallest of Bluesound’s multiroom speakers, taking its place alongside the larger Pulse 2, Pulse Mini and Pulse Soundbar. Its ultra compact design musically refreshes parts of the house other speakers cannot reach, including the garden if you clip on the optional battery pack and turn it fully portable.
Like all of Bluesound’s wireless speakers, Flex boasts Wi-Fi, aptX Bluetooth and multiroom streaming via the BluOS controller app, which offers a wide range of music streaming services. But its most unusual talent is MQA playback, the audio codec that squeezes hi-res music into smaller file sizes for streaming and downloading without compromising on quality.
Both the Pulse 2 and Pulse Mini wowed us with their heavyweight build and dashing designs, and Flex is a chip off the old block. It’s only 180mm tall but surprisingly hefty for its size (always an encouraging sign) and the soft matt finish (in white or black) lends an air of quality. The curved corners and chiselled back end mimic the shape of the Pulse 2 and Mini, although unlike its Bluesound brethren the front grille is flat, not curved. An optional Flex bracket lets you mount it on the wall.
It’s just a gorgeous, solidly-made speaker that fully justifies the asking price. The air of luxury continues on top with a glossy panel of buttons, which you’ll be forever polishing to remove fingerprints. The controls include volume, play and track skip, plus five numbered presets that store internet radio stations and streaming service playlists. An LED on the front indicates the Flex’s status.
On the back is a combined optical/analogue 3.5mm input, headphones output and a USB port for music playback from storage devices. Connect the Ethernet port to your router for a more stable streaming connection.
Further up the rear panel is terminal for the optional £69 BP100 battery pack, hidden behind a rubber cover when not in use. The pack clicks securely into place and disconnects by pressing the button on the back. It sticks out a little awkwardly, but the matching matt finish at least provides some visual continuity. It charges while the speaker is plugged into the mains and gives you six hours of playback.
Bluesound Pulse Flex – Features
Pulse Flex boasts the same 1GHz ARM Cortex A9 multi-core processor used as the larger models, alongside a digital amplifier that delivers 2 x 20W of power. The two-way speaker employs a 3.5-inch woofer and 1-inch tweeter.
Multiroom playback and music streaming come courtesy of the BluOS app, available free for Android and iOS devices. It supports a wide range of streaming services, including Spotify, TIDAL, Napster, Qobuz, Deezer, KKBox, Groove Music, WiMP, HDTracks and Murfie, plus internet radio from TuneIn, iHeartRadio, Calm and Radio Paradise.
Some of the services, like Spotify, require a premium account and stream from their own app; others, like Qobuz and Deezer are built into BluOS.
Hi-res format support includes MQA, FLAC, WAV, AIFF and ALAC up to 192kHz/24-bit, as well as MP3, AAC and WMA. The app can send different sources to each speaker in your system, or play the same music through a group of speakers.
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Bluesound Pulse Flex – Setup and Operation
As explored in my review of the Pulse Mini, the BluOS app is terrific in many ways but not without its flaws. You can play music from NAS drives on your network, but with no uPnP or DLNA support the process of loading your tracks is more confusing than most multiroom speakers.
It involves setting up a network share and indexing the contents of your server. If like me you have a large collection of files it can take quite a long time to index them all, and whenever you add new tunes to your collection you have to re-index the library manually. It’s hardly rocket science, but feels clunky.
Wi-Fi setup is also less intuitive than most rivals. You have to connect your phone to the speaker via Wi-Fi, then visit a browser page and punch in your router credentials. Most multiroom apps do all this for you.
But once you’re up and running the BluOS app is a joy to use. It’s navigated using two sidebar menus – one containing a list of sources and services, the other a list of connected Bluesound speakers. Find your own music by tapping ‘Library’ and scrolling through the grid of album covers. The list can be filtered to display MQA and/or hi-res files only.
Elsewhere you can configure presets and favourites, create speaker groups in the My Players menu and check Flex’s remaining battery life. The app looks simple, professional and operates at quickly.
Bluesound Pulse Flex – Performance
Naturally the Flex could never hope to match the room-filling muscle of the Pulse 2 or even the Mini, but it has a damn good try. It sounds bigger and louder than a speaker of this size has any right to, streaming tunes with Bluesound’s characteristic combination of power and polish.
If bass is your bag, Flex has you covered. Musical genres that require a big bottom-end thump, like hip-hop and electronica, aren’t left wanting thanks to the woofer’s deep, punchy kick drums and basslines. Points by James Blake is punctuated by big, falling bass notes and the Bluesound tracks their descent to visceral effect.
The groovy funk bassline underpinning 1975 by Incognito has plenty of weight and agility, reinforced on the beat by a tight bass drum. There’s a lovely solidity to the sound that you don’t always get from a speaker of this size, and for that Bluesound should be applauded.
Despite its impressive bass output, Flex’s sound is remarkably well balanced. In the midrange, vocals are clear, detailed and full-bodied. Higher up, Flex whispers sweet nothings in your ear with soft, silky treble. There’s ample snap in snare drums hits, but it also captures their subtle papery quality. Hi-hats are crisp but not in your face. If you don’t like the Flex’s default tonal balance you can adjust bass and treble within the BluOS app.
Flex ups the ante with hi-res material, offering even greater clarity and bass definition. An MQA-encoded 96/24 FLAC of Uprising by Muse stomps along with rumbling drums and rousing guitar riffs. The Doctor Who-like synth glides over a deep saw-toothed bassline. Jazz tune My Favourite Things by Paul Novotny and Robi Botos sounds simply gorgeous. Each chocolatey double bass note is defined by a clean twang, while the piano solos dance and sparkle with glassy elegance.
Impressive though it is, there are little reminders of its size and position in the Pulse family. It doesn’t handle loud volumes as well as Pulse Mini – treble sounds a little sharp and edgy, and bass notes lose composure. The soundstage is also narrower than the Pulse 2 and Mini, although it’s still more open than its physical dimensions would suggest.
If you’re a Bluesound fanboy with other Pulse speakers already ensconced in your home, then Flex is an essential addition. And if you’re not, its lower price and compact design make it a great place to start.
Flex is blessed with premium build quality, fast operation and powerful sound that belies its compact dimensions. It supports a wide range of hi-res formats (including MQA) and streaming services in the attractive BluOS app. Even better news is that the optional battery pack allows you to enjoy Flex’s sumptuous sound quality wherever you go.
The clunky, non-DLNA network sharing and browser-based setup are a chore, but thankfully don’t completely derail an otherwise superb streaming experience.
Flex’s luxurious design, versatile operation and sweet sound quality live up to Bluesound’s high standards, but the lack of DLNA/uPnP makes network setup clunky