Headsets and headphones / Compare

Marshall Monitor III A.N.C. vs Sonos Ace

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Product A: Marshall

Monitor III A.N.C.

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B

Product B: Sonos

Ace

67 of 161 known

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Only differences

AMarshall Monitor III A.N.C.

BSonos Ace

General

6 of 8 differ

Series

Monitor1Press releasegroup.marshall.com/2024/09/25/marshall-and-billie-joe-armstrong-join-forces-to-unveil-feature-packed-monitor-iii-a-n-c-headphonesRead 23 October 2026

Not available

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

MONITIII, 1006861, 1009077, 10091633Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Public maker page product data lists orderable US Black 1006861, Cream 1009077 and Pitch Black 1009163. Regulatory MONITIII comes from FCC filing.

ACEG1US1BLK, ACEG1US11Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Page data lists SKU ACEG1US1BLK for Black and ACEG1US1 for Soft White. These are US SKUs.

GTIN / EAN

7340055401777, 73400554114794Retailer pageargos.co.uk/product/3347382/GM-VariantRead 23 October 2026Exact UK Black model 1006861 EAN. Other Argos hardware specs contain errors and are not substituted for maker data.42Retailer pagebhphotovideo.com/c/product/1958585-REG/marshall_1009077_monitor_iii_a_n_c_wireless.html/overviewRead 23 October 2026Exact Cream SKU 1009077 EAN 7340055411479.

Not available

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

24 September 20242Press articlenotebookcheck.com/Marshall-stellt-neue-kabellose-ANC-Kopfhoerer-Monitor-III-A-N-C-vor.890514.0.htmlRead 23 October 2026Contemporaneous September 24, 2024 German launch report says announced today. Maker corporate post is dated September 25, one day after stated retail availability.

21 May 20247Press articletomsguide.com/audio/headphones/sonos-officially-unveils-its-first-wireless-headphones-heres-everything-you-need-to-know-about-the-sonos-aceRead 11 October 2026Sonos Ace announced May 21, 2024.

Status

Available1Press releasegroup.marshall.com/2024/09/25/marshall-and-billie-joe-armstrong-join-forces-to-unveil-feature-packed-monitor-iii-a-n-c-headphonesRead 23 October 2026Launch from September 24, 2024. Current maker page still lists orderable colors.

Available1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Sold on the maker US store, currently at $239 against a $349 list price.

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

Not available

Not available

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.

Not available

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.

Not available

$4497Press articletomsguide.com/audio/headphones/sonos-officially-unveils-its-first-wireless-headphones-heres-everything-you-need-to-know-about-the-sonos-aceRead 11 October 2026Expected prices at the announcement: USD $449 / GBP 449 / EUR 499 / AUD $699. TechCrunch and What Hi-Fi? also give $449.

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.

€3492Press articlenotebookcheck.com/Marshall-stellt-neue-kabellose-ANC-Kopfhoerer-Monitor-III-A-N-C-vor.890514.0.htmlRead 23 October 2026Contemporaneous German launch report names 349 EUR at Marshall and retailers. Consumer price including VAT as published. The Black launch finish is covered. Later Cream and Pitch Black launch prices are not established.

€4997Press articletomsguide.com/audio/headphones/sonos-officially-unveils-its-first-wireless-headphones-heres-everything-you-need-to-know-about-the-sonos-aceRead 11 October 2026Expected EUR 499 at the announcement. Digital Trends gives EUR 499 as the 2024 launch price. Tax treatment is not stated.8Press articledigitaltrends.com/home-theater/sonos-ace-ultra-may-launch-cheaper-than-the-original-ace-new-leak-revealsRead 11 October 2026The Ace launched in 2024 at EUR 499.

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

US, GB, DE3Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026US maker store. UK Black GTIN from Argos and German launch availability from Notebookcheck. Not a global list.

Not available

ColoursiThe maker's own colour names

Black, Cream, Pitch Black3Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Current exact-model maker colorways. Hardware is presented as one marketed model.

Black, Soft White1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Colors: Black, Soft White. Finish: Matte.

Segment

Music1Press releasegroup.marshall.com/2024/09/25/marshall-and-billie-joe-armstrong-join-forces-to-unveil-feature-packed-monitor-iii-a-n-c-headphonesRead 23 October 2026Maker describes music listening headphones in Monitor line.

Music1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Maker markets it as noise-canceling headphones for music, spatial audio and TV listening.

Design

1 of 7 differ

Form factor

Over-ear5Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026Manual cover over-ear headphones.

Over-ear1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Over-ear headphones. The page and What Hi-Fi? call them over-ear.

Ear cup enclosureiClosed, open or semi-open acoustic enclosure. This does not describe how the headset folds.

Closed6Reviewsoundguys.com/marshall-monitor-iii-anc-review-a-worthy-alternative-to-sony-and-bose-131654Read 23 October 2026Exact-model FAQ explicitly closed-back headphones.

Closed4Reviewwhathifi.com/reviews/sonos-aceRead 11 October 2026The TrueCinema section says the aim is not to feel like you are wearing closed-back headphones, which describes the Ace as closed-back. HeadphoneCheck lists the type as closed.5Reviewheadphonecheck.com/test/sonos-aceRead 11 October 2026Technical specifications: Type closed, ear coupling over-ear, transducer principle dynamic.

Wearing style

Headband5Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026

Headband2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Extendable stainless steel headband with rotating ear cups.

FoldingiFlat means the ear cups rotate flat. Inward means the ear cups fold toward the headband.

Flat and inward5Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026Printed page 6 hard-case instructions rotate left/right cups and fold inward until pads meet.

Flat4Reviewwhathifi.com/reviews/sonos-aceRead 11 October 2026The ear cups swivel flat but do not fold up. Shotkit also says they do not fold.

Swivelling ear cupsiEar cups can rotate relative to the headband. Tilting alone does not count.

Yes5Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026Printed page 6 explicitly rotates left counterclockwise and right clockwise.

Yes2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026The extendable stainless steel headband and rotating ear cups adjust for a bespoke fit.4Reviewwhathifi.com/reviews/sonos-aceRead 11 October 2026The ear cups swivel flat.

RGB lighting

Not available

Not available

Lighting zonesiNumber of independently controllable lighting areas across both ear cups.

Not available

Not available

Drivers and sound

9 of 20 differ

Driver type

Dynamic7Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026

Dynamic1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Custom-designed 40 mm dynamic driver in each cup.

Driver sizeiDiameter of the largest sound driver. Do not use the microphone capsule diameter.

32mm7Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026

40mm1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Custom-designed 40 mm dynamic driver in each cup.

Drivers per sideiNumber of sound-producing transducers in one side, excluding microphones.

Not available

11Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Custom-designed 40 mm dynamic driver in each cup.

Diaphragm material

Not available

Not available

Magnet

Not available

Not available

Frequency response (wired or passive)iPublished acoustic range for wired listening, or the maker’s single range when no mode is distinguished. Power state and test standard belong in the source note.

Min20 HzMax20 kHz7Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Current single frequency range 20-20,000 Hz. Mode and test tolerance unspecified. Not a wireless passband.

Not available

Wireless audio transmission bandiFrequency range of audio transmitted over the wireless connection, not the acoustic response of the driver. Codec, sampling rate and bitrate conditions belong in the source note. When the maker gives a range per codec, the widest range is stored and its codec goes in the source note.

Not available

Not available

Impedance (passive when specified)iUse the headset-off value for a passive analog connection when the maker publishes both powered and passive values. Note the power state and test frequency.

46Ω7Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Current maker audio specification 46 ohm. Earlier secondary reviews give 35 ohm. Current maker wins. No passive power-off impedance claimed.

Not available

Sensitivity (passive when specified)iUse the headset-off figure when both powered and passive values exist. The power or voltage reference, test distance and frequency belong in the source note.

91dB7Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Current maker 91 dB SPL at -18 dBFS, 1 kHz. This is not per 1 mW or per 1 V, so sensitivity_reference omitted. Earlier reviewers quote different sensitivity references.

Not available

Sensitivity referenceiPublished power or voltage reference for sensitivity. Do not assume 1 mW when the source gives only a dB value.

Not available

Not available

THD (claimed)iPublished distortion figure or numerical upper bound. The source note states any less-than sign and test level.

Not available

Not available

Max input power

Not available

Not available

Max digital audio sample rateiHighest supported digital audio sample rate over a USB cable or wireless dongle. This is not the microphone rate or acoustic frequency response.

Not available

48kHz4Reviewwhathifi.com/reviews/sonos-aceRead 11 October 2026Connected to a laptop over USB-C, the headphones support sample rates of 16-bit/48kHz.

Max digital audio bit depthiHighest published digital playback bit depth over a USB cable or wireless dongle.

Not available

16bits4Reviewwhathifi.com/reviews/sonos-aceRead 11 October 2026Connected to a laptop over USB-C, the headphones support sample rates of 16-bit/48kHz.

DAC

Not available

Not available

Personalised soundiA manufacturer-supported hearing test or ear scan creates a device sound profile tailored to the listener. Generic equalizer adjustments do not count.

Not available

Not available

Onboard EQiCustom playback EQ profiles stored in the headset and applied without the host app running. Note supported active connections. Receiver-only or software-only EQ does not count.

Not available

Not available

Custom EQ bandsiNumber of bands in the custom playback equalizer. Microphone EQ bands are excluded.

58Reviewsoundguys.com/marshall-monitor-iii-anc-review-a-worthy-alternative-to-sony-and-bose-131654Read 23 October 2026App section five-band custom playback EQ. HeadphoneCheck corroborates. Five presets are stated but a complete exact name list is not published.

Not available

EQ presets

Bass Boost9Reviewtechradar.com/audio/wireless-headphones/marshall-monitor-iii-anc-reviewRead 23 October 2026Review explicitly names bass boost. Full factory-name list was not independently verified, so only the named option is stored.

Not available

Volume limit

Not available

Not available

Spatial audio

2 of 3 differ

Spatial audio supportiNamed headset or host spatial-audio systems that the maker or reviewer explicitly supports. A platform feature may require compatible hardware, software or a separate licence.

Soundstage10Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Maker named Soundstage spatial processing of stereo content into a virtual room. Head tracking not established.

Dolby Atmos1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Dolby Atmos requires a supported Sonos soundbar and the Sonos app for TV Audio Swap. Spatial audio from supported services and devices works over Bluetooth.

Spatial audio licence includediA paid spatial-audio licence is bundled or embedded. Compatibility with a separately purchased app does not count.

Not available

Not available

Head tracking

Not available

Yes1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Sonos Intelligent Motion Processing with Dolby Head Tracking. Enable it in the Sonos app. The Sonos Ace must be registered in the app.

Noise cancelling

3 of 10 differ

Active noise cancelling

Yes11Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Maker active noise cancellation. No topology or total physical microphone count specified.

Yes1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Active Noise Cancellation dynamically adapts to fit, blocking external sounds. Aware mode blends ambient sound with the content.

ANC typeiFeedforward uses outside microphones. Feedback uses inside microphones. Hybrid uses both. Voice-call noise filtering is separate.

Not available

Not available

ANC microphonesiTotal microphones used for active playback noise cancellation across both sides. Do not substitute the total physical or voice microphone count.

415Reviewnotebookcheck.com/Exklusiv-zum-Markstart-Marshall-Monitor-III-A-N-C-im-Praxis-Test-Tolles-Design-wie-ist-der-Klang.890386.0.htmlRead 23 October 2026Equipment section explicitly four microphones continuously record surrounding noise for ANC, increased from two. It does not establish speech microphone count or physical total.

Not available

Adaptive ANCiNoise cancellation automatically changes with the environment or fit. Manually choosing a level does not count.

Yes14Reviewheadphonecheck.com/test/marshall-monitor-iii-a-n-cRead 23 October 2026ANC section explicitly describes adaptive noise cancelling. Maker does not name a specific adaptive ANC mode. Adaptive Loudness remains a separate sound feature.

Yes1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Active Noise Cancellation dynamically adapts to fit and surroundings.

ANC levelsiNumber of adjustable cancellation strength steps. Off and transparency modes are excluded.

314Reviewheadphonecheck.com/test/marshall-monitor-iii-a-n-cRead 23 October 2026Controls section explicitly three intensity levels for ANC, separately from three transparency levels. Off is excluded.

Not available

ANC attenuation (claimed)

Not available

Not available

Transparency mode

Yes11Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026

Yes1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Aware mode blends ambient sound with your content.

Adjustable transparency

Yes11Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Common question Soundstage sliders are not used here. Exact noise-control support guide and SoundGuys explicitly adjustable transparency.13Reviewsoundguys.com/marshall-monitor-iii-anc-review-a-worthy-alternative-to-sony-and-bose-131654Read 23 October 2026Noise cancelling section explicitly three adjustable transparency levels.

Not available

Conversation detectioniAudio pauses or lowers automatically when the wearer speaks. Voice assistant activation does not count.

Not available

Not available

Wind noise reduction

Yes11Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Maker corporate launch explicitly microphones designed to reduce wind noise for ANC and calls. A claim, not a measured attenuation value.12Press releasegroup.marshall.com/2024/09/25/marshall-and-billie-joe-armstrong-join-forces-to-unveil-feature-packed-monitor-iii-a-n-c-headphonesRead 23 October 2026Launch text explicitly reduction of wind noise for ANC and calls.

Yes1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Specially engineered mesh over the microphones minimizes noise from wind on phone calls.

Measured

5 of 21 differ

Frequency response notesiMeasured by a reviewer, not claimed by the maker

The measured default response has more bass and treble and less midrange than the SoundGuys Preference Curve. ANC off adds some bass.17Reviewsoundguys.com/marshall-monitor-iii-anc-review-a-worthy-alternative-to-sony-and-bose-131654Read 23 October 2026Objective Measurements section. Default profile, nominal level, ANC-on comparison with ANC-off. Firmware and exact codec not published. No chart points converted into numeric dB fields.

Not available

Bass amountiReviewer’s bass deviation from its stated target. Positive is more bass. Target and test method belong in the source note.

Not available

Not available

Treble amountiReviewer’s treble deviation from its stated target. Positive is more treble. Target and test method belong in the source note.

Not available

Not available

Deviation from targetiReviewer’s full-range error from its target curve. Do not substitute a regional bass or treble error.

Not available

Not available

Consistency between fittingsiReviewer’s standard deviation across repeated fittings. Test rig and fitting procedure belong in the source note.

Not available

Not available

Harmonic distortioniIndependently measured harmonic distortion, with test level and method in the source note.

Not available

Not available

Sound leakageiIndependently measured leakage at 30 cm. Playback level and method belong in the source note.

Not available

Not available

Measured noise isolationiIndependently measured attenuation. Positive values mean more noise reduction. ANC state, rig and frequency bands belong in the source note.

Not available

Not available

Noise isolation (measured, best)iMeasured by a reviewer, not claimed by the maker

Not available

Not available

Passive isolation (measured)iMeasured by a reviewer, not claimed by the maker

Not available

Not available

Mic quality notesiMeasured by a reviewer, not claimed by the maker

The recorded samples reject background noise well but lose vocal clarity. Loud speech can clip. Wind, street, office and reverberant conditions were tested.17Reviewsoundguys.com/marshall-monitor-iii-anc-review-a-worthy-alternative-to-sony-and-bose-131654Read 23 October 2026Recorded speech samples in simulated office, street, wind and reverberant conditions. Test codec, firmware and capture route are unpublished. The vote count is not a measurement.

Not available

Mic low-frequency extensioniMeasured by a reviewer, not claimed by the maker

Not available

Not available

Mic high-frequency extensioniMeasured by a reviewer, not claimed by the maker

Not available

Not available

Mic speech-to-noise ratioiMeasured by a reviewer, not claimed by the maker

Not available

Not available

Measured latencyiEnd-to-end latency measured by a reviewer for a specific connection, platform and codec. Firmware, method and operating mode belong in the source note.

Not available

Not available

Bluetooth latency (measured, worst)iMeasured by a reviewer, not claimed by the maker

Not available

Not available

2.4 GHz latency (measured, worst)iMeasured by a reviewer, not claimed by the maker

Not available

Not available

Measured battery lifeiReviewer’s continuous playback test. State the connection, ANC and lighting where known. Unknown settings stay omitted and are described in the source note.

AMarshall Monitor III A.N.C.

Connection	ANC	Hours (h)
Bluetooth	Yes	68
Bluetooth	No	110.32

Source16Reviewchip.de/test-kaufberatung/tv-audio/marshall-monitor-iii-a-n-c-im-test_a4725ea6-a9f4-4e8b-aa22-0f51f8c0d1c3.htmlRead 23 October 2026Tested July 11, 2026. Full-runtime table 68 h 00 min ANC on and 110 h 19 min off. CHIP describes continuous fixed-playlist Bluetooth playback at the same calibrated volume across products. Numeric SPL, codec, firmware and spatial-processing state unpublished. 110 h 19 min converted to hours. Partial 15-minute-charge runtimes excluded. SoundGuys could not complete its separate battery test and contributes no runtime.

BSonos Ace

Not available

Battery life (measured, max)iMeasured by a reviewer, not claimed by the maker

110.32h=CalculatedFrom Measured battery life

Not available

Clamping forceiMeasured by a reviewer, not claimed by the maker

Not available

Not available

Weight (measured)iIndependently weighed headset. A review that repeats the maker’s number does not qualify. Cable and microphone inclusion belong in the source note.

253g(8.9 oz)16Reviewchip.de/test-kaufberatung/tv-audio/marshall-monitor-iii-a-n-c-im-test_a4725ea6-a9f4-4e8b-aa22-0f51f8c0d1c3.htmlRead 23 October 2026Independent CHIP test table 253 g. Cable inclusion not stated. Maker claims 250 g.

313g(11 oz)5Reviewheadphonecheck.com/test/sonos-aceRead 11 October 2026Weighed by HeadphoneCheck: 313 g without cable and 329 g with cable.

Microphone

3 of 16 differ

MicrophoneiMain microphone used for speech. Secondary internal microphones may be described in the source note.

Built-in18Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Audio specification explicitly Microphone & Remote yes and maker describes phone-call handling. No unsupported speech-mic count, pattern or element added.

Built-in2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Eight microphones in the ear cups for noise control and voice targeting. No boom microphone.

Microphone element

Not available

Not available

Microphone pickup patterniUse the maker’s exact named pattern. Unidirectional does not establish whether the capsule is cardioid, supercardioid or hypercardioid.

Not available

Not available

Voice microphonesiTotal microphones used for voice pickup or beamforming across both sides. ANC-only microphones are excluded.

Not available

Not available

Total microphonesiEvery physical microphone across the headset, including call, ANC and calibration microphones. Shared microphones count once. Excludes microphones in charging cases or receivers, and vibration sensors. Use an explicitly published physical total, never a sum of overlapping role counts.

Not available

81Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Eight microphones for noise control and voice targeting. The maker states the total for the headset.

Mic frequency responseiAcoustic microphone response, not its digital sampling rate. Connection-specific ranges belong in the source note.

Not available

Not available

Mic sensitivityiPublished microphone sensitivity. Reference such as dBV/Pa or dBFS, frequency and distance belong in the source note.

Not available

Not available

Mic signal-to-noiseiPublished microphone signal-to-noise ratio. Minimum or typical conditions belong in the source note.

Not available

Not available

Mic sample rateiExplicitly published digital microphone capture or speech sampling rate. State the audio route in the source note, or say it is unpublished. Internal capture does not prove the effective rate on every connection. Acoustic bandwidth, playback rate and generic microphone-chip capability do not qualify.

Not available

Not available

Mic noise reductioniProcessing that removes noise from transmitted speech. Playback ANC and a directional microphone alone do not count.

Not available

DSP1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Beamforming microphones target your voice and suppress background noise on calls. Stored as DSP processing. The maker does not claim AI processing.

Flip to mute

Not available

Not available

Mute button

Not available

Not available

Mute indicatoriPublished indication of microphone mute. mechanical_marker is a visible physical marker showing the microphone's mute-switch position. LED options require an electronic light. The in-line controller option is for a mute light on a cable remote.

Not available

Not available

Sidetone

Not available

Yes1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Sidetone helps you hear your own voice when Active Noise Cancellation is enabled.2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Sidetone is a setting in the Sonos app Noise Control section. It may not work when the headphones are plugged into another device during a call.

Adjustable sidetone

Not available

Not available

Foam microphone windscreeniA foam cover for the voice microphone. An internal metal mesh pop filter does not count.

Not available

Not available

Connectivity

9 of 20 differ

Audio connectionsiConnections that carry playback audio. Charging or firmware USB alone does not count as USB audio.

Bluetooth, Analog19Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026Printed pages 4 and 7 included USB-C-to-3.5 mm cable carries analog source audio. USB-C shape does not imply USB digital playback.

Bluetooth, USB, Analog2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Bluetooth. The USB-C port also takes line-in audio over a USB-C to 3.5 mm cable (for analog sources) or a USB-C to USB-C cable. Bluetooth is disabled while a USB-C cable is connected.

Analog source plugsiAnalog plug(s) supplied for the source device, including adapters. The headset-side jack is listed separately.

3.5 mm TRS41Retailer pagebhphotovideo.com/c/product/1854727-REG/marshall_1006861_monitor_iii_anc_wireless.htmlRead 23 October 2026Exact Black 1006861 overview and supplied-items list explicitly USB-C to 3.5 mm TRS cable. Other B&H specification errors such as open-back enclosure and LC3 are not used.

Not available

Cable connector on headsetiConnection used by the playback cable at the headset. A fixed cable is not replaceable through a headset jack.

USB-C19Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026

USB-C2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Both included cables plug into the headset USB-C port. The 3.5 mm cable is not compatible with third party cables.

Longest included cableiLength of the longest supplied cable, including charging and dongle cables. Individual cable lengths are listed in Cables included.

Not available

1.2m1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Longest included cable is the USB-C to 3.5 mm cable, 3.94 ft (1.2 m).

Headset USB plug or portiUSB plug or port on the headset or its included wired audio adapter. A charging-only USB port can appear here.

USB-C19Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026

USB-C2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026USB-C port for charging and line-in.

Audio over USB-C cableiPlayback through a USB-C cable or included wired USB-C audio adapter. A charging-only USB-C port does not count.

No21Reviewchip.de/test-kaufberatung/tv-audio/marshall-monitor-iii-a-n-c-im-test_a4725ea6-a9f4-4e8b-aa22-0f51f8c0d1c3.htmlRead 23 October 2026Independent exact-model table explicitly USB-C-Audio no. Included 3.5 mm-to-USB-C analog cable is a separate path. ifanr exact review independently explicitly rules out USB Audio.

Yes1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Lossless audio over Bluetooth with a supported device or via a USB-C connection. The page also says to use the USB-C cable for wired listening.

Passive wired listeningiAnalog playback works with the headset powered off or its battery empty. An active analog converter that needs headset power does not count.

No19Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026Printed page 7 requires headphones on before connecting analog cable. HeadphoneCheck and CHIP confirm no passive playback. Tom's Guide claims otherwise, but maker instructions take precedence.

No5Reviewheadphonecheck.com/test/sonos-aceRead 11 October 2026The USB-C to 3.5 mm cable still needs the headphones switched on. MusicTech says they do not work in passive mode over 3.5 mm.6Reviewmusictech.com/reviews/consumer/sonos-ace-reviewRead 11 October 2026They do not work in passive mode over 3.5 mm. They always have to be on and charged.

Wireless receiveriDedicated wireless audio receiver or dongle. A wired USB sound card does not count.

Not available

None2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Bluetooth headphones. No dongle in the box.

Wireless receiver connectoriPhysical USB connector on the receiver. Supplied extension cables and adapters are explained in the source note. Both means two native connector types.

Not available

Not available

Wireless range (claimed)iMaker’s advertised wireless range. Connection and indoor or outdoor conditions belong in the source note. Measured distance is not stored here.

10m20Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Current maker 10 m / 30 ft claim. Meters retained. Conditions not specified.

Not available

Bluetooth

5.320Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026

5.41Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Bluetooth 5.4

Bluetooth codecsiNamed Bluetooth audio codecs supported by this exact model. Host, firmware and operating-mode restrictions belong in the source note.

SBC, AAC20Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Current maker Codecs SBC, MPEG-2 AAC. AAC stored using common catalog spelling. LE Audio-ready is not confirmed current LC3 support.

SBC, AAC, aptX HD, aptX Adaptive, aptX Adaptive Low Latency, aptX Lossless3Maker product pagesupport.sonos.com/en/article/supported-bluetooth-audio-formats-for-sonos-aceRead 11 October 2026Maker article lists SBC, AAC, aptX Lossless, aptX Adaptive, aptX Adaptive Low Latency and aptX HD. The page text says Sonos headphones. The article URL names the Sonos Ace. Lossless over Bluetooth needs an Android device with Qualcomm Snapdragon Sound aptX for Lossless. What Hi-Fi? and HeadphoneCheck list only SBC, AAC and aptX Lossless.4Reviewwhathifi.com/reviews/sonos-aceRead 11 October 2026Tech specs list SBC, AAC and aptX Lossless. The maker support article lists more aptX variants and is stored.

LE AudioiLE Audio playback support. Bluetooth Low Energy for app control alone does not count.

Not available

Not available

AuracastiAuracast broadcast audio support. Required phone, firmware and app conditions belong in the source note.

Not available

Not available

Bluetooth multipointiCan remain connected to multiple Bluetooth source devices at once. Mixing Bluetooth with a proprietary dongle is a separate field. A maker's dual connection to two Bluetooth devices at once counts.

Yes19Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026

Yes1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Sonos Ace must be registered in the Sonos app to enable Bluetooth multipoint.

Multipoint devicesiNumber of Bluetooth source devices connected at once, not the number remembered for later pairing.

219Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026Printed page 8 explicitly two connected devices simultaneously.

22Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026You can connect Sonos Ace to 2 Bluetooth devices and automatically switch between audio streams. Multipoint is off by default.

Paired devices remembered

819Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026Printed page 8 explicitly remembers eight paired devices.

Not available

Mixes 2.4 GHz and Bluetooth audioiPlays both wireless audio streams at the same time. Automatic switching or Bluetooth standby does not count.

Not available

Not available

Fast pairing

Not available

Not available

Base station

Not available

Not available

Latency

None of 2 known

Low latency modeiA selectable mode intended to reduce audio delay. A low-latency connection without a distinct mode does not count.

Not available

Not available

Claimed latencyiMaker’s claimed delay for the stated connection and mode. Minimum claims and host restrictions belong in the source note.

Not available

Not available

Compatibility

1 of 3 differ

Compatible platformsiPlatforms with a documented audio path. This does not imply every connection or microphone function works. Platform editions must be checked individually.

Android, iOS22Maker product pagemarshall.com/us/en/support/headphones/learn/app-marshall-bluetoothRead 23 October 2026Maker app page lists exact model and Apple App Store/Google Play downloads. Exact-model setup guide requires pairing host device with headphones. No desktop/console audio path inferred.

Android, iOS1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Page says Works with Apple and Android.

Connection per platformiOnly explicitly documented playback paths for the exact model. Microphone support is separate. Leave unknown microphone support omitted. An Xbox and a PlayStation edition of one headset can connect differently, so it is per variant.

AMarshall Monitor III A.N.C.

Platform	Connection
Android	Bluetooth
iOS	Bluetooth

Source22Maker product pagemarshall.com/us/en/support/headphones/learn/app-marshall-bluetoothRead 23 October 2026Supported mobile setup uses Bluetooth pairing. Per-platform call microphone support is left unspecified.

BSonos Ace

Not available

Official licence

Not available

Not available

Battery and charging

9 of 13 differ

Battery capacityiRated capacity of one headset battery. Do not use case, receiver or total multi-battery capacity.

Not available

1,060mAh1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Li-ion, 1060 mAh battery

Swappable batteryiBattery can be exchanged by the user as part of normal operation. Service or recycling disassembly does not count.

Not available

Not available

Batteries includediNumber of headset batteries supplied, including the one already installed.

224Press articlenotebookcheck.com/Marshall-stellt-neue-kabellose-ANC-Kopfhoerer-Monitor-III-A-N-C-vor.890514.0.htmlRead 23 October 2026Exact-model German launch report explicitly a double battery with one pack in each earcup. No per-pack capacity published. No total mAh divided or guessed.

Not available

Claimed battery lifeiMaker’s maximum playback time per stated connection, codec, ANC, spatial audio and lighting settings. Name the spatial processing mode and other conditions in the source note. Unknown settings stay omitted.

AMarshall Monitor III A.N.C.

Connection	ANC	Hours (h)
Bluetooth	Yes	70
Bluetooth	No	100

Source23Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Current maker battery specification explicitly Bluetooth plus ANC 70 h and Bluetooth only 100 h. Volume, codec, spatial processing and firmware not stated.

BSonos Ace

Connection	ANC	Hours (h)
Bluetooth	Yes	30

Source1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Up to 30 hours of listening time or 24 hours of call time with Active Noise Cancellation or Aware mode enabled. Stored as the 30 hour listening claim. The 24 hour call time is not stored. The page says battery life varies by use and settings.

Battery life (claimed, max)

100h=CalculatedFrom Claimed battery life

30h=CalculatedFrom Claimed battery life

Battery life with ANC (claimed)

70h=CalculatedFrom Claimed battery life

30h=CalculatedFrom Claimed battery life

Battery life without ANC (claimed)

100h=CalculatedFrom Claimed battery life

Not available

Charging port

USB-C23Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026

USB-C1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Charge with the included USB-C cable and a compatible power adapter.

Full charge timeiPublished time to fully charge a depleted headset. In-use charging can take longer.

150min23Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Maker 2.5 h to full recharge converted exactly to 150 minutes.

180min1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Complete charge from 0% requires up to 3 hours. Stored as 180 minutes, the upper bound.

Quick charge timeiCharge duration in the maker’s quick-charge claim. Read together with Quick charge playback.

15min23Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026

3min1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Rapid charge provides 3 hours of listening time in 3 minutes from 0%.

Quick charge playbackiPlayback gained from Quick charge time. Charger power, codec, volume and ANC conditions belong in the source note.

12h23Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Maker 15 minutes supplies 12 hours. ANC, codec and volume unspecified.

3h1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Rapid charge provides 3 hours of listening time in 3 minutes from 0%.

Use while charging

Not available

Not available

Charging dock or stand

Not available

Not available

Controls

3 of 6 differ

Controls

Buttons25Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026Printed pages 4-5 two buttons and multidirectional control knob. Knob moves by directional pushes, not a rotating dial or wheel. No schema joystick option exists.

Buttons, Slider2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Content Key slides for volume and presses for playback, plus a Noise Control button and a Power/Bluetooth button. What Hi-Fi? calls the Content Key a slider and button.4Reviewwhathifi.com/reviews/sonos-aceRead 11 October 2026Physical (not touch) controls. A multi-functional slider and button called the content key.

Volume control

Not available

Not available

Game and chat mixiBalances separate game and chat audio streams. Mixing Bluetooth and dongle source volume alone does not count. Supported platforms belong in the source note.

Not available

Not available

Remappable controlsiOn-device button, touch or dial functions can be reassigned. Changing EQ alone does not count.

Yes25Owner's manualdownloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdfRead 23 October 2026Printed page 5 M-button assignment in app. Default Spotify Tap.

Not available

Wear detection

Yes26Reviewsoundguys.com/marshall-monitor-iii-anc-review-a-worthy-alternative-to-sony-and-bose-131654Read 23 October 2026Controls section explicitly wear sensor and automatic playback pause when removed.

Yes1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Feature list: Wear detection.2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Wear detection is enabled by default and can be turned off in the Sonos app.

Voice assistant

Phone's voice assistant43Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Customisable M-button activates the phone's voice assistant. Maker names no specific service. It is host activation, separate from the Voice command No row for built-in voice control.

Voice assistant of the connected device2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Press and hold the Noise Control / Voice Control button to activate the voice assistant on the connected device.

Comfort and build

7 of 11 differ

Headband type

Not available

Padded5Reviewheadphonecheck.com/test/sonos-aceRead 11 October 2026The headband is well padded on the underside and trimmed with artificial leather.

Headband material

Silicone inner headband27Reviewnotebookcheck.com/Exklusiv-zum-Markstart-Marshall-Monitor-III-A-N-C-im-Praxis-Test-Tolles-Design-wie-ist-der-Klang.890386.0.htmlRead 23 October 2026Design section explicitly silicone inner band attached at the sides. Does not establish outer upholstery material.

Not available

Frame material

Not available

Stainless steel2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026The stainless steel headband smoothly extends and stays securely in place.

Ear cup material

Plastic27Reviewnotebookcheck.com/Exklusiv-zum-Markstart-Marshall-Monitor-III-A-N-C-im-Praxis-Test-Tolles-Design-wie-ist-der-Klang.890386.0.htmlRead 23 October 2026Design section explicitly flexible plastic cup shell. Decorative leather-like texture is not treated as leather shell.

Not available

Ear pad material

Vegan leather and foam28Retailer pageargos.co.uk/product/3347382/GM-VariantRead 23 October 2026Exact Black listing names Vegan Leather and Foam ear pieces. Not interpreted as natural leather.

Memory foam covered in vegan leather4Reviewwhathifi.com/reviews/sonos-aceRead 11 October 2026The ear pads use memory foam coated in a layer of vegan leather (polyurethane).

Replaceable ear pads

Yes29Owner's manualdownloads.ctfassets.net/javen7msabdh/2hCtX2YRHbepO0vP6hwRex/437db6a71a057973414ed7d097217311/Monitor-III-ANC-spareparts_user-manual_all-languages.pdfRead 23 October 2026

Yes1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Replaceable ear cushions help extend the life of the headphones.2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Ear cushion replacement section.

Ear pad attachmentiHow a replacement ear pad attaches to the ear cup, not how the decorative outer cover attaches. A press-fit or snap-on pad counts as clip.

Twist lock29Owner's manualdownloads.ctfassets.net/javen7msabdh/2hCtX2YRHbepO0vP6hwRex/437db6a71a057973414ed7d097217311/Monitor-III-ANC-spareparts_user-manual_all-languages.pdfRead 23 October 2026Printed page 3 rotate anticlockwise to remove and clockwise to lock.

Magnetic2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Each cushion is held in place by magnets and comes off with a light pull. It snaps into place when reattached.4Reviewwhathifi.com/reviews/sonos-aceRead 11 October 2026The replaceable ear pads are attached to the frame by strong magnets.

Ear pad openingiUsable opening inside an ear pad, excluding the outer cushion. Depth is the internal space between pad surface and driver cover.

Not available

Not available

Ear tips included

Not available

Not available

Dust and water rating

Not available

Not available

User-replaceable parts

Ear cushions, Inner headband29Owner's manualdownloads.ctfassets.net/javen7msabdh/2hCtX2YRHbepO0vP6hwRex/437db6a71a057973414ed7d097217311/Monitor-III-ANC-spareparts_user-manual_all-languages.pdfRead 23 October 2026Printed pages 3-5 exact replacement procedures. Inner headband uses T5 Torx screwdriver. Battery is not in this user replacement manual.

Ear cushions2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Ear cushions can be easily replaced if they wear out.

Software

1 of 3 differ

Companion app

Marshall Bluetooth30Maker product pagemarshall.com/us/en/support/headphones/learn/app-marshall-bluetoothRead 23 October 2026

Sonos2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Use the Sonos app to adjust product settings.

App platforms

Android, iOS30Maker product pagemarshall.com/us/en/support/headphones/learn/app-marshall-bluetoothRead 23 October 2026Maker lists exact model with Apple App Store and Google Play links.

Android, iOS2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Sonos app (iOS and Android).

User firmware updates

Yes30Maker product pagemarshall.com/us/en/support/headphones/learn/app-marshall-bluetoothRead 23 October 2026Exact-model support page explicitly app firmware updates.31Maker product pagemarshall.com/us/en/support/headphones/support-for-monitor-iii-ancRead 23 October 2026Update the firmware section explicitly app updates for Monitor III A.N.C.

Yes2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Sonos app About screen: check for software updates and see the current software version.

Dimensions and weight

2 of 2 differ

Headset weightiPublished headset mass without detachable cable or microphone when stated. A fixed cable remains included. Any unqualified maker weight is identified in the source note.

250g(8.8 oz)32Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Current maker physical-unit table 250 g. No cable qualification stated. SoundGuys and CHIP measured information stays separate.

312g(11 oz)1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Weight 0.69 lbs (0.312 kg)

Headset dimensionsiBody size with headband upright and ear cups in their normal wearing position. Width is across the head, height is top to bottom, and depth is front to back. Folded or flat-swivel dimensions are not substituted.

Not available

Width160Height191Depth85mm(6.3 × 7.5 × 3.3 in)1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Height 7.52 in (191 mm), Width 6.3 in (160 mm), Depth 3.35 in (85 mm)

Certifications

0 of 3 differ

Hi-Res Audio

Not available

Not available

Communication certifications

Not available

Not available

FCC ID

2BBQK-MONITIII33Regulatory filingfccid.io/2BBQK-MONITIIIRead 23 October 2026Public FCC filing index for exact MONITIII headphone, approved April 29, 2024. Referenced label/internal documents could not be downloaded because of access denial. No hidden exhibit data used.

Not available

Other certifications

Not available

Not available

In the box

2 of 3 differ

In the box

Monitor III A.N.C. Headphones, USB-C charging cable, USB-C to 3.5mm audio cord, Quick start guide, Legal and Safety Information, Carrying case34Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026

Sonos Ace headphones, USB-C to USB-C cable, USB-C to 3.5 mm cable, Travel case with removable cable pouch, Set up guide and legal and warranty information1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026Box contents: Sonos Ace, USB-C to USB-C cable, USB-C to 3.5 mm cable, travel case that includes a removable cable pouch, set up guide and legal and warranty information.

Cables includediSupplied playback, charging, dongle and adapter cables. A permanently attached headset cable is included and named as fixed.

AMarshall Monitor III A.N.C.

Type	Length (m)	Count
USB-C to USB-C charging cable	0.21	1
USB-C to 3.5 mm stereo audio cable	Not available	1

Source34Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Maker box list confirms both cables. Manual page 4 confirms USB-C-to-USB-C charging lead. HeadphoneCheck states 21 cm charging lead. Audio length is omitted because HeadphoneCheck says 120 cm and SoundGuys says 122 cm while maker is silent.35Reviewheadphonecheck.com/test/marshall-monitor-iii-a-n-cRead 23 October 2026Scope of delivery explicitly charging cable 21 cm and analog cable 120 cm. Only uncontested charging length retained. SoundGuys metadata says 122 cm for analog cable.

BSonos Ace

Type	Length (m)	Count
USB-C to USB-C cable	0.75	1
USB-C to 3.5 mm cable	1.2	1

Source1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026USB-C to USB-C cable 2.46 ft (0.75 m). USB-C to 3.5 mm cable 3.94 ft (1.2 m).

Carrying caseiSupplied carrying case or pouch. A retail carton does not count as a carrying case.

Hard34Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026Maker explicitly hard case, also described in manual page 6.

Hard5Reviewheadphonecheck.com/test/sonos-aceRead 11 October 2026The Ace arrives in a felt-covered hard case made of recycled plastic with a zip. Shotkit calls it semi-hard.

Links

Not compared

Product page

www.marshall.com/us/en/product/monitor-iii-anc36Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026

www.sonos.com/en-us/shop/sonos-ace1Maker product pagesonos.com/en-us/shop/sonos-aceRead 11 October 2026

Spec sheet

www.marshall.com/us/en/product/monitor-iii-anc36Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026

Not available

Manual

downloads.ctfassets.net/javen7msabdh/Y4lwjaW2ma8v33Kx2ZXCz/d55009139a27c6786e45675a034af6e2/Marshall-Monitor-III-ANC-All-Languages.pdf36Maker product pagemarshall.com/us/en/product/monitor-iii-ancRead 23 October 2026

www.sonos.com/en-us/guides/sonosace2Owner's manualsonos.com/en-us/guides/sonosaceRead 11 October 2026Sonos Ace product guide.

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

Not available

Warranty

1 of 1 differ

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.

1year37Maker product pagemarshall.com/us/en/support/warrantyRead 23 October 2026US support default warranty one year from purchase. Online Marshall purchases receive an exclusive two-year term. Base field stores default term, separate from legal guarantees.

Not available

Both are also in the API. Back to all headsets and headphones.