Wireless speakers / Compare

Bose SoundLink Flex Bluetooth Speaker vs Ultimate Ears BOOM 4

A

Product A: Bose

SoundLink Flex Bluetooth Speaker

40 of 96 known

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B

Product B: Ultimate Ears

BOOM 4

51 of 96 known

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All 96 fields

Every value links to where we found it.

Only differences

ABose SoundLink Flex Bluetooth Speaker

BUltimate Ears BOOM 4

General

5 of 8 differ

Series

SoundLink2Maker product pagebose.ca/en/p/bose-soundlink-flex-bluetooth-speaker/SLFLX-SPEAKERWIRELESS-WHTSM-WW.htmlRead 13 October 2026Bose lists the speaker in its SoundLink family of portable Bluetooth speakers. iFixit lists the same family.

BOOM1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

Model numbersiMaker identifiers for this exact model and its listed variants. Excludes sibling models and other generations.

865983-0100, 4359101Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Regulatory section of the owner's guide lists Type designation 435910 for the Bluetooth speaker. SoundGuys lists 865983-0100 for the US Black item.3Reviewsoundguys.com/bose-soundlink-flex-review-63268Read 13 October 2026Review lists Model Number 865983-0100, the US Black item.

S001762Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

GTIN / EAN

Not available

Not available

AnnouncediThe maker's first announcement of this model. This is separate from first retail availability.

Not available

26 June 20243Press releasenews.logitech.com/press-releases/news-details/2024/The-Rugged-Ultimate-Ears-EVERBOOM-Superior-Sound-That-Is-Waterproof-Dustproof-and-Floatable/default.aspxRead 8 October 2026

Status

Not available

Available1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

PredecessoriThe model this one directly replaced, in the same line, tier and size, as the maker or a trusted review names it.

Not available

Ultimate Ears BOOM 38Reviewtrustedreviews.com/reviews/ultimate-ears-boom-4Read 10 October 2026Trusted Reviews says a successor to the UE Boom 3 finally arrived in the Boom 4.9Measurementrtings.com/speaker/reviews/ultimate-ears/boom-3Read 23 October 2026RTINGS shows a notice on the BOOM 3 page that it was replaced by the Ultimate Ears BOOM 4.

SuccessoriThe model that directly replaced this one, in the same line, tier and size. A revision such as a Slim or OLED model does not count when a next generation exists.

Bose SoundLink Flex Portable Speaker (2nd Gen)8Reviewsoundguys.com/bose-soundlink-flex-2nd-gen-review-125253Read 13 October 2026Review calls the SoundLink Flex (2nd Gen) the follow-up to the original SoundLink Flex that came out in 2021. The 2nd Gen has Bluetooth 5.3 and the Bose app.

Not available

Launch price (US)iThe maker's US launch MSRP for the stated configuration, excluding tax. Current store prices and later discounts do not qualify.

$1493Reviewsoundguys.com/bose-soundlink-flex-review-63268Read 13 October 2026Review lists an original price of 149 USD. T3 and What Hi-Fi also give 149 USD. Tax treatment is not stated.

$149.993Press releasenews.logitech.com/press-releases/news-details/2024/The-Rugged-Ultimate-Ears-EVERBOOM-Superior-Sound-That-Is-Waterproof-Dustproof-and-Floatable/default.aspxRead 8 October 2026US launch MSRP $149.99 before tax.

Launch price (EU)iThe maker's euro launch price for the stated configuration, including VAT as published. Current store prices and later discounts do not qualify.

Not available

Not available

MarketsiISO country or region codes where this exact model or variant is sold. A source page's language does not establish availability.

US3Reviewsoundguys.com/bose-soundlink-flex-review-63268Read 13 October 2026US price in USD and the US Black model number 865983-0100.

US1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

ColoursiThe maker's own colour names

Not available

Raspberry Red, Enchanting Lilac, Active Black, Cobalt Blue1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

Speaker typeiHome covers speakers made to stay in one place, including smart speakers. A speaker with Wi-Fi or a voice assistant can be of any type.

Portable7Spec databaseifixit.com/Device/SoundLink_FlexRead 13 October 2026iFixit describes a portable Bluetooth speaker.

Portable1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

Audio

10 of 18 differ

Audio channelsiSound channels reproduced by one speaker. Pairing two speakers for stereo is separate.

Not available

Stereo4Reviewrtings.com/speaker/reviews/ultimate-ears/boom-4Read 8 October 2026Public Music verdict describes the single BOOM 4 unit stereo capabilities and soundstage performance. Two-unit stereo linking is a separate field and is not inferred from PartyUp.

Audio driversiPowered audio transducers in one speaker. Passive radiators are counted separately. Circular diameter and rectangular width and height have separate columns. Per-driver power must state continuous or RMS basis and battery or mains operation in the source note.

ABose SoundLink Flex Bluetooth Speaker

Driver type	Count
Full-range dynamic driver	1

Source6Reviewt3.com/us/reviews/bose-soundlink-flex-reviewRead 13 October 2026Review says the driver array is a single full-range dynamic driver. Bose does not publish its size or power.

BUltimate Ears BOOM 4

Driver type	Count	Diameter (mm)
Active audio driver	2	40

Source1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026Specs and Compatibility: two 1.57 in (40 mm) active drivers and two 1.81 x 2.57 in (46.1 x 65.2 mm) passive radiators. Support page lists rounded 2 inch sizes. Rated power not published.2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026Support Speaker Specifications: two active drivers and two passive radiators. Support lists a rounded 2 inch driver. The maker product page and Trusted Reviews give 40 mm, which is stored. The support passive radiator size of 2 x 4 inch also differs from the product page 46.1 x 65.2 mm, so the support sizes are treated as rounded.8Reviewtrustedreviews.com/reviews/ultimate-ears-boom-4Read 10 October 2026Full specs list 2x 40mm active drivers.

Passive radiatorsiPassive, unpowered bass radiators. Excludes powered drivers.

26Reviewt3.com/us/reviews/bose-soundlink-flex-reviewRead 13 October 2026Review says the single driver is supplemented by a couple of racetrack passive radiators, so two.

22Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

Rated audio poweriMaker-published total rated continuous audio output. Battery power is used for portable speakers when mains and battery ratings differ. Peak marketing power is separate.

Not available

Not available

Rated audio power on mainsiTotal rated continuous audio output with external power. Store a separate battery rating when the maker publishes both.

Not available

Not available

Audio output power (unspecified rating)iMaker- or reviewer-published audio output power whose continuous or peak rating basis is not stated. This is separate from rated continuous output and explicitly published peak output.

Not available

Not available

Peak audio poweriExplicitly published peak audio output. Never substitute for rated continuous output.

Not available

Not available

Frequency response lower limit (claimed)iPublished acoustic frequency response limit. Tolerance and operating mode belong in the source note. The Bluetooth transmission range that some spec tables and retailers label Frequency Response, such as A2DP 20 to 20,000 Hz, is not stored.

Not available

90Hz2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026Maker claim 90 Hz to 20 kHz. No tolerance or test settings stated.

Frequency response upper limit (claimed)iPublished acoustic frequency response limit. Tolerance and operating mode belong in the source note. The Bluetooth transmission range that some spec tables and retailers label Frequency Response, such as A2DP 20 to 20,000 Hz, is not stored.

Not available

20kHz2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026Maker claim 90 Hz to 20 kHz. No tolerance or test settings stated.

Signal-to-noise ratio (claimed)

Not available

Not available

Adjustable equalizeriUser-adjustable frequency bands. Selecting fixed sound presets alone does not qualify.

No5Reviewtomsguide.com/audio/bluetooth-speakers/bose-soundlink-flex-reviewRead 13 October 2026Review lists no customizable EQ as a con. T3 also says there is no EQ in the app.

Yes2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

Equalizer bandsiNumber of user-adjustable frequency bands. Do not count sound presets.

Not available

Not available

Automatic sound adjustmentiAdjusts audio to placement or playback conditions. Keep the named feature and conditions in the source note.

Yes4Reviewwhathifi.com/reviews/bose-soundlink-flexRead 13 October 2026Review says PositionIQ technology uses built-in sensors to detect the speaker's orientation and adjusts the sound to it.

Not available

Sound modesiNamed playback modes. Battery extension modes are also qualified in battery source notes.

Not available

Signature, Bass Boost, Cramped Space, Deep Relaxation, Podcast/Vocal1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026Key features: Signature sound plus four pre-set EQ modes in the UE | BOOM app: Bass Boost, Cramped Space, Deep Relaxation and Podcast/Vocal.

Wireless stereo pairingiTwo compatible speakers can play separate left and right channels.

Yes1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Owner's guide (PDF created March 2024) describes Stereo mode with a second compatible speaker: SoundLink Micro, Flex, Color II, Revolve and Revolve+ (Series I and II). It does not work with the 2nd Gen Flex, which uses a different app.

Not available

Speaker link protocolsiNamed systems for linking compatible speakers, such as PartyBoost, Auracast or Party Connect. Linking support does not establish compatibility across all models.

Bose Party Mode, Bose Stereo Mode, Bose SimpleSync1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Party mode and Stereo mode for two Bose Bluetooth speakers, and SimpleSync to link with a Bose Smart Speaker or Soundbar through the Bose app.

PartyUp1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026PartyUp compatible with BOOM, MEGABOOM, EVERBOOM, EPICBOOM and HYPERBOOM. Product page says over 150 speakers. The Getting Started guide says up to 150, see max_linked_speakers.

Max linked speakersiPublished maximum in a speaker group. A stereo pair is recorded separately. A figure such as 100+ is stored as 100.

21Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide says pair two Bose Bluetooth speakers for Party mode or Stereo mode. SimpleSync pairs with only one Bose product at a time.

1505Owner's manualsupport.logi.com/hc/en-us/articles/17139015562519-Getting-Started-UE-BOOM-4Read 10 October 2026UE | BOOM app section: Party Up pairs up to 150 speakers. Any BOOM, MEGABOOM, EVERBOOM, EPICBOOM or HYPERBOOM can join. Product page says over 150, the guide figure is stored. Linking is app based, so the Bluetooth group field is not set.

Max Bluetooth group speakersiPublished maximum speakers in one Bluetooth playback group, including the first speaker. Source notes name the compatible models or families, linking system and firmware requirements. Wi-Fi groups and concurrent Bluetooth source devices are excluded. A stereo pair alone does not establish the maximum when other Bluetooth linking systems are supported. A figure such as 100+ is stored as 100.

Not available

Not available

Connectivity

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Bluetooth audio playbackiPlays audio streamed over Bluetooth from a phone or other source. Bluetooth used only for setup or app control does not count.

Yes3Reviewsoundguys.com/bose-soundlink-flex-review-63268Read 13 October 2026

Yes2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

Bluetooth versioniVersion of the Bluetooth radio. Some Wi-Fi speakers use Bluetooth only for setup. See Bluetooth audio playback.

4.23Reviewsoundguys.com/bose-soundlink-flex-review-63268Read 13 October 2026Review says Bluetooth 4.2 with the SBC codec only. Bose 2nd Gen coverage also says the original uses Bluetooth 4.2.

5.02Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

Bluetooth codecsiExplicitly supported receive codecs. Bluetooth version alone does not establish codecs.

SBC3Reviewsoundguys.com/bose-soundlink-flex-review-63268Read 13 October 2026Review says only the standard SBC codec is supported. This is a reviewer statement and not a maker document.

SBC2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

Bluetooth profiles

Not available

A2DP2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

Bluetooth LE AudioiExplicit LE Audio support. Bluetooth LE for app control alone does not qualify.

Not available

Not available

AuracastiExplicit Auracast support. Sending, receiving and speaker-group roles belong in source notes.

Not available

Not available

MultipointiConcurrent Bluetooth source connections. Pairing memory and speaker-to-speaker linking do not qualify.

Yes1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide says the speaker can be actively connected to two devices at a time and plays audio from one device at a time.

No4Reviewrtings.com/speaker/reviews/ultimate-ears/boom-4Read 8 October 2026Public Music/Outdoors verdict explicitly lists no Bluetooth multi-device pairing.

Multipoint source devicesiMaximum concurrently connected Bluetooth source devices, not remembered pairings.

21Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Up to two actively connected devices. Up to eight devices are stored in the pairing list.

Not available

Bluetooth range (claimed)iMaker-claimed Bluetooth range to the source device. Test conditions belong in the source note.

9m1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide gives a Bluetooth range of 30 ft or 9 m.

45m2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

Wi-FiiBuilt-in Wi-Fi, for audio streaming, setup or control.

Not available

No4Reviewrtings.com/speaker/reviews/ultimate-ears/boom-4Read 8 October 2026Public Wi-Fi row explicitly says No.

Wi-Fi standardsiOne 802.11 name per item, such as 802.11ax. A Wi-Fi generation is written as its standard, so Wi-Fi 5 is 802.11ac and Wi-Fi 6 is 802.11ax. Older standards are listed only when a source names them.

Not available

Not available

Network audio protocolsiNamed systems that stream audio to the speaker over the home network. AirPlay is written as AirPlay 2. Chromecast built-in is written as Google Cast. Other names follow the maker, such as Spotify Connect.

Not available

Not available

USB audio inputiPlayback from a connected computer or phone through USB. Charging, service ports and USB flash-drive playback do not qualify.

Not available

No2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026Connection Type is Bluetooth. Wireless speaker, charging by USB-C cable. USB-C is documented for charging only.

USB drive playbackiPlayback of audio files on a connected USB storage device.

Not available

Not available

USB audio file formats

Not available

Not available

PortsiPhysical speaker connectors. Record charging, audio input, power output and service roles separately. A shared microphone and guitar jack is one port. A combo jack that takes XLR and 6.35 mm plugs is 6.35 mm audio, and the role names XLR. Optical is a TOSLINK digital audio socket.

ABose SoundLink Flex Bluetooth Speaker

Connector	Count	Role
USB-C	1	Charging input

Source1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide says charge with the USB-C cable and shows no other connector. SoundGuys confirms there is no aux input.

BUltimate Ears BOOM 4

Connector	Count	Role
USB-C	1	Charging input

Source2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026Speaker is charged via USB-C. Device input voltage/current not established by the separately listed adapter rating.

Controls and software

5 of 8 differ

SpeakerphoneiBuilt-in microphone and call support, through a connected phone or a voice assistant's calling. A microphone used only for voice commands does not count. Microphone inputs for karaoke are separate.

Yes1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide documents answering, ending, declining and muting calls with the built-in microphone.

No2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

Voice assistantsiVoice assistants explicitly usable through the speaker, such as Amazon Alexa, Google Assistant, Siri or Sonos Voice Control. State whether a connected phone is required.

Connected phone voice assistant1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide says the speaker microphone extends the phone's microphone and press and hold of the multi-function button opens the voice assistant on the connected device.

Not available

Controls

Power, Bluetooth pairing, Play/pause, Next/previous track, Volume up/down, Answer/end call, Voice assistant1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide lists Power, Bluetooth, Volume up and down and a multi-function button: press for play/pause and answer/end call, twice for skip forward, three times for skip backward, hold for voice control.

Power, Bluetooth pairing, Volume up/down, Play/pause, Next/previous track, Magic Button playlist shortcut, Battery level2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

Companion app

Bose Connect1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide names the Bose Connect app for setup, Bluetooth connections and settings. The Bose app is needed for SimpleSync.

UE | BOOM2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

App platforms

iOS, Android2Maker product pagebose.ca/en/p/bose-soundlink-flex-bluetooth-speaker/SLFLX-SPEAKERWIRELESS-WHTSM-WW.htmlRead 13 October 2026Page says apps are available on Google Play and the Apple Store.

iOS, Android2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

User firmware updates

Yes1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide says the speaker receives security updates through the Bose Connect app and software updates can be run in the app.

Yes5Owner's manualsupport.logi.com/hc/en-us/articles/17139015562519-Getting-Started-UE-BOOM-4Read 10 October 2026Speaker Updates and Party Up instructions explicitly document OTA firmware updates from the UE | BOOM app.

Built-in lightingiDecorative or ambient lighting. Status, battery, connection and microphone indicator LEDs alone do not qualify.

Not available

No2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026Indicator Lights lists four LEDs: power, Bluetooth, Magic button and one charging LED. No decorative lighting is listed.

Lighting modes

Not available

Not available

Smart home

None of 3 known

Matter controlleriCan add and control Matter devices. Being a Matter device alone does not count.

Not available

Not available

Thread border routeriConnects Thread smart home devices to the home network.

Not available

Not available

Zigbee hubiA built-in Zigbee radio that controls Zigbee smart home devices.

Not available

Not available

Battery and charging

5 of 17 differ

Built-in battery

Yes1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide describes a rechargeable lithium-ion battery that is not to be removed by the user.

Yes1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

Playback time (claimed)iMaximum maker-claimed music playback on one charge in normal playback mode. Battery extension or reduced-bass boost modes belong in battery_life_boost_h. Record volume and lighting conditions in the source note.

12h1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide says with typical usage the battery lasts up to 12 hours and varies with content and volume.

15h1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026Up to 15 hours. Varies with settings, volume and environmental conditions. High volume and bass boost reduce runtime.

Playback with battery extension (claimed)iTotal claimed runtime with the named battery extension mode enabled. Store the total, not only the extra hours. Keep sound and lighting restrictions in the source note.

Not available

Not available

Battery energyiPublished battery pack energy. Do not calculate from an assumed voltage.

Not available

11.52Wh2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026Built-in Li-ion rechargeable battery 11.52 Wh. No pack voltage or mAh inferred.

Battery capacityiPublished pack capacity at the voltage in battery_voltage_v. Do not substitute power-bank output capacity. A figure written per cell, such as 5000mAh*2, is not a pack capacity unless the maker states the pack figure.

Not available

Not available

Nominal battery voltage

Not available

Not available

Battery chemistry

Lithium-ion1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide regulatory text names a rechargeable lithium-ion battery.

Lithium-ion1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

User-replaceable batteryiBattery that the maker documents as replaceable by the user. Service replacement does not qualify.

Not available

No2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026Battery user replaceable: Not recommended, improper assembly may affect waterproof performance. Maker does not document user replacement.

Full charge timeiTime from discharged to full under the maker conditions. Adapter rating and simultaneous use belong in source notes.

4h1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide says allow up to 4 hours to fully charge the battery. No adapter is included.

3h2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026Battery Charge Speed: less than 3 hours from empty to full with a Type C charger of 7.5 W or above. Stored as 3, the qualifier is here.

Quick charge duration

Not available

Not available

Playback after quick chargeiClaimed music playback after quick_charge_min of charging. Source conditions apply.

Not available

Not available

Charging input ratingiPublished speaker input voltage and current. An adapter rating alone does not establish device input.

5 V DC at 1.5 A1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Regulatory section lists Input Rating 5Vdc, 1.5A.

Not available

Max charging inputiPublished maximum charging input. USB audio power requirements and adapter output are separate.

Not available

Not available

USB Power Delivery charging

Not available

Not available

Charges other devices

Not available

Not available

Max power-bank outputiPublished power delivered by the speaker to another device. Output voltage and current belong in the source note.

Not available

Not available

Wireless chargingiThe speaker battery can be charged wirelessly. Wireless power output to another device is separate.

Not available

Not available

Durability

4 of 5 differ

Dust and water ratingiExact published IP rating. Keep separate ratings, such as IP68 and IP69, as separate entries.

IP67, IP641Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide says the speaker is rated IP67 and IP64 and can be immersed for up to 30 minutes at a depth of up to 1 m.

IP671Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

Floats

Not available

Yes1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

Drop resistanceiExplicit maker claim or defined drop test. Do not infer from rugged wording.

Not available

Yes1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

Drop test heightiMaker-published tested height. Surface and conditions belong in source notes.

Not available

Not available

Carry featuresiPublished handles, straps, carabiners or wheels.

Built-in strap1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026Guide says the strap works as a finger loop or attaches to a carabiner or a cord.

Bungee loop1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

Measured

1 of 6 differ

Playback time (measured)iReviewer-measured playback per charge. Volume, lighting, sound mode, firmware and connection belong in the source note.

11.98h3Reviewsoundguys.com/bose-soundlink-flex-review-63268Read 13 October 2026Review reports 11 hours 59 minutes, which is 11.98 h, in the standard test: continuous music at a 75 dB (SPL) maximum output level measured 1 m from the front of the speaker. Firmware and codec are not stated.

12h6Measurementrtings.com/speaker/reviews/ultimate-ears/boom-4Read 10 October 2026Public Outdoors verdict states 12 hours of battery life for the tested BOOM 4. Locked numeric tables were not read. Maker claim is 15 hours.7Measurementrtings.com/speaker/tests/active-features/batteryRead 10 October 2026Public method: latest firmware, full charge, audio track looped at 80 dB SPL from 1 m until the speaker runs out of charge. Speaker-specific sound mode, EQ and firmware are not published.

Max sound pressure (measured)iReviewer-measured maximum SPL. Distance, test method and power source belong in source notes.

Not available

Not available

Low-frequency extension (measured)iReviewer-measured low-frequency limit. Threshold and test method belong in source notes.

Not available

Not available

High-frequency extension (measured)iReviewer-measured high-frequency limit. Threshold and test method belong in source notes.

Not available

Not available

Audio latency (measured)iReviewer-measured source-to-speaker latency. Source device, app, codec, firmware and connection belong in source notes. App compensation may affect results.

Not available

Not available

Full charge time (measured)iReviewer-measured time from empty to full. Power adapter and method belong in the source note.

Not available

Not available

Dimensions and weight

3 of 3 differ

DimensionsiSpeaker body width, height and depth on explicitly identified axes. Unlabeled tuples do not establish axis meanings. Handle, strap and orientation conditions belong in the source note.

Width201Height90Depth52mm(7.9 × 3.5 × 2 in)4Reviewwhathifi.com/reviews/bose-soundlink-flexRead 13 October 2026Review spec box lists Dimensions (hwd) 9 x 20.1 x 5.2cm, so height 90 mm, width 201 mm, depth 52 mm. Bose's own inch figures 3.56 H x 7.93 W x 2.06 D as reproduced by iFixit agree.

Width73Height184Depth73mm(2.9 × 7.2 × 2.9 in)2Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026Product Dimensions table, Speaker row explicitly labels height 184, width 73, depth 73 mm. Packaging row excluded.

WeightiSpeaker mass including its battery. Excludes packaging, charger and removable carry accessories unless the source states otherwise.

589g(1.3 lb)3Reviewsoundguys.com/bose-soundlink-flex-review-63268Read 13 October 2026Review spec box lists 589g. Bose's own spec as reproduced by iFixit is 1.300 lb.

620g(1.4 lb)1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

Body materials

Aluminum, Fabric, Nylon, Plastic, Silicone, Steel7Spec databaseifixit.com/Device/SoundLink_FlexRead 13 October 2026Product Material Aluminum, Fabric, Nylon, Plastic, Silicone, Steel, as in Bose's own specification.

Post-consumer recycled plastic, Recycled polyester fabric3Press releasenews.logitech.com/press-releases/news-details/2024/The-Rugged-Ultimate-Ears-EVERBOOM-Superior-Sound-That-Is-Waterproof-Dustproof-and-Floatable/default.aspxRead 8 October 2026BOOM 4 plastic components minimum 52% PCR by weight. Fabric is 100% PCR polyester. Packaging excluded.

Certifications

None of 1 known

FCC IDs

Not available

Not available

Other certifications

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In the box

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In the box

Speaker, USB Type-C cable2Maker product pagebose.ca/en/p/bose-soundlink-flex-bluetooth-speaker/SLFLX-SPEAKERWIRELESS-WHTSM-WW.htmlRead 13 October 2026What's in the box: Bose SoundLink Flex Bluetooth speaker and USB Type-C cable. SoundGuys says the cable is USB-C to USB-A.

Not available

Links

Not compared

Product page

www.bose.ca/en/p/bose-soundlink-flex-bluetooth-speaker/SLFLX-SPEAKERWIRELESS-WHTSM-WW.html2Maker product pagebose.ca/en/p/bose-soundlink-flex-bluetooth-speaker/SLFLX-SPEAKERWIRELESS-WHTSM-WW.htmlRead 13 October 2026Maker's Canadian product page. The page shows the speaker as sold out and the US page has been removed.

www.ultimateears.com/en-us/shop/p/boom-41Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026

Spec sheet

Not available

support.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-42Maker product pagesupport.logi.com/hc/en-us/articles/17139015760279-Specification-BOOM-4Read 10 October 2026

Manual

assets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdf1Owner's manualassets.bosecreative.com/m/43ab91c25d0ac95a/original/866666_OG_SLFLX-SPEAKERWIRELESS_enUS.pdfRead 13 October 2026

support.logi.com/hc/en-us/articles/17139015562519-Getting-Started-UE-BOOM-45Owner's manualsupport.logi.com/hc/en-us/articles/17139015562519-Getting-Started-UE-BOOM-4Read 10 October 2026Official getting-started manual explicitly covers BOOM 4 and MEGABOOM 4.

EPREL registration numberiId in the EU energy label database. Each size or model of a series has its own id, so it is per variant.

Not available

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Warranty

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Manufacturer warranty (source market)iThe maker's warranty period for the exact SKU or configuration and market named in the source note. It applies only to that stated market, not every regional variant. Statutory consumer rights are excluded. The base term is stored. An extension that needs registration goes in the source note.

Not available

2years1Maker product pageultimateears.com/en-us/shop/p/boom-4Read 10 October 2026US page embedded specs and compatibility: 2-Year Limited Hardware Warranty.

Both are also in the API. Back to all wireless speakers.