Bose SoundLink Flex (2nd Gen) vs Ultimate Ears BOOM 4

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SoundLink Flex (2nd Gen) compared with BOOM 4

	BoseSoundLink Flex (2nd Gen)	Ultimate EarsBOOM 4
Overview
Released
Released	September 2024	June 2024
Sound
Type
Type	Portable speaker	Portable speaker
Dolby Atmos
Dolby Atmos	No	No
Drivers
Drivers	–	Two 40 mm active drivers and two 46.1 × 65.2 mm passive radiators; 360° sound; maximum sound level 85 dBC
Room tuning
Room tuning	PositionIQ senses the speaker's orientation and adjusts the sound; adjustable EQ in the Bose app	–
Connections
Wi-Fi
Wi-Fi	No	No
Bluetooth
Bluetooth	Yes	Yes
AirPlay
AirPlay	No	No
Voice assistants
Voice assistants	None	None
Bluetooth
Bluetooth	Bluetooth 5.3 with a 9 m range; multipoint connection to two devices; aptX Adaptive with Snapdragon Sound devices	Bluetooth (version not published); 45 m range
Ports
Ports	USB-C (charging)	USB-C for charging
Streaming
Streaming	Bluetooth; the shortcut button can start Spotify Tap	–
Multi-room
Multi-room	Stereo Mode with a second Flex (2nd Gen), or Party Mode with another current SoundLink speaker (Micro 2nd Gen, Plus or Max); SimpleSync with Bose smart soundbars and speakers	PartyUp in the UE | BOOM app with over 150 BOOM, MEGABOOM, EVERBOOM, EPICBOOM and HYPERBOOM speakers
App
App	Bose app	UE | BOOM app, including Megaphone
Design
Battery life (maker's claim)
Battery life (maker's claim)	Up to 12 hours	Up to 15 hours
Water and dust resistance
Water and dust resistance	IP67	IP67
Weight
Weight	0.59 kg (better)	0.62 kg
Battery life detail
Battery life detail	Up to 12 hours; up to 3 hours at maximum volume; up to 4 hours to charge; no power adapter included	Up to 15 hours; charges over USB-C (cable not included)
Controls
Controls	Buttons on top, including a programmable shortcut button (linking two speakers by default; Spotify Tap or the phone's voice assistant)	Magic Button for play, pause, skip and one-touch playlists (Spotify, Amazon Music, Apple Music on iOS)
Microphones
Microphones	Built-in microphone for speakerphone calls	–
Mounting
Mounting	Nylon utility loop for carrying or clipping to a bag	Bungee loop attached
Size
Size	2.06 × 7.93 × 3.56 in (H × W × D); 1.291 lb	184 mm tall, 73 mm across
Colours
Colours	Black, Blue Dusk, Alpine Sage and Sandstone, plus limited editions; Bose UK currently sells Dewdrop Mint	–
In the box
In the box	SoundLink Flex (2nd Gen), USB-C to USB-A cable, safety sheet	BOOM 4 with attached bungee, quick start guide printed inside the box