Compare Marshall Monitor III A.N.C. Over-Ear Bluetooth Headphones vs DALI IO-12 Headphones

ANC is consistently described as solid to above average and improved versus the prior model, but most sources still place it behind top-tier Bose or Sony performance. You can adjust ANC strength in the app and set how the ANC button cycles modes; the common complaint is the lack of true adaptive ANC that auto-adjusts for you.

ANC is broadly described as effective for reducing low rumbles and general ambient noise, but it is not considered class-leading compared with flagship Bose, Sony, or Apple models; some mention susceptibility to wind noise. Noise cancellation adjustability is limited to onboard mode switching in most coverage, with some sources noting multiple ANC modes, but no fine tuning via app.

Android support is good for basics (pairing features, LE Audio readiness), but Android users who want aptX or LDAC will find those codecs missing.

The Marshall app is generally well-liked for being clean and functional, giving access to firmware, EQ, ANC levels, control customization, and battery-care features.

Multiple sources confirm there is no companion app for the IO-12.

Reviews that address aptX note it is not supported, which can be a downside for some Android users.

Multiple reviews explicitly cite aptX options, including higher-tier variants such as aptX HD and aptX Adaptive, as part of the IO-12 wireless feature set.

Some reviewers flag potential latency for gaming because low-latency Bluetooth codecs are missing; wired USB-C listening is the safer option when sync matters.

Bass hits with satisfying punch and extension for most listeners, but it is not a true bass-cannon and some reviewers want a stronger bass-boost or tighter control.

Bass is typically described as tight and controlled in Hi-Fi mode with convincing weight, while Bass mode adds slam and warmth without turning into a boomy mess, though it can trade away some treble presence.

Battery life is the headline feature: 70 hours with ANC on and up to 100 hours with ANC off is repeatedly highlighted and often backed up by real-world use. The battery is not generally described as user-replaceable; Marshall instead focuses on battery preservation settings to help extend lifespan.

Battery life is commonly cited around 35 hours, with at least one real-world report closer to 30 hours; overall it is respectable but not exceptional relative to cheaper competitors.

Bluetooth stability is generally reliable in daily use, with Bluetooth 5.3 and LE Audio readiness mentioned and few drop-out complaints.

Bluetooth connectivity is commonly reported as stable, with fast pairing and few to no dropouts even in busy environments.

Build quality is generally rugged and travel-ready with an emphasis on durability and repairability, though a few sources mention minor creaks or quirks.

Build quality is repeatedly described as ultra-premium, with strong materials and a luxury feel that holds up to travel use when handled with care.

The multi-directional control knob and dedicated buttons are widely praised as intuitive, tactile, and easier to use than touch controls.

Buttons are often praised for responsiveness and tactile feedback, but a few reviewers mention accidental activation, especially when adjusting volume or leaning against a seat while traveling.

Cable quality and design are serviceable, with included cables for charging and wired use, but some miss the older coiled cable style or find adapters less convenient.

Cable quality feedback is mixed: some appreciate the included cables and finish, while at least one reviewer calls the cable frustrating to use and prefers the shorter option.

The included hard case gets high marks for protection and premium feel (velvet interior, compact footprint), though a few find it thick or bulgy.

The carry case is typically praised as premium and protective, with good structure and compartments, but it adds bulk and can be impractical for compact packing.

Charging is fast and convenient via USB-C, with common claims of about 12 hours of playback from a short charge and full recharge around a couple of hours.

Charging is described as taking roughly 1.5 to 2 hours from flat with no fast-charge boost mentioned, and one reviewer notes behavior consistent with limiting charge to protect long-term battery health.

Clamping force is generally light, with multiple reviewers reporting minimal pressure and little to no head squeeze.

Clamping force is usually described as secure but comfortable, ranging from light to moderately firm depending on the reviewer, without feeling unstable.

Codec support is basic for the price: SBC and AAC are the norm, with some mentions of LE Audio/LC3, but there is no mainstream hi-res Bluetooth path.

Codec support is positioned as strong for a premium wireless headphone, with repeated mentions of AAC and aptX-family options that help preserve detail over Bluetooth.

Long-session comfort is a standout: low weight, plush pads, and pressure-distributing headband design earn frequent praise, with only occasional complaints about heat buildup.

Long-session comfort is one of the most consistently praised aspects, with roomy earcups and plush pads that avoid pressure points for many listeners.

Design is classic Marshall amp-inspired with textured finishes and brass/gold accents; it feels premium to fans but can be polarizing for those who prefer modern styling.

Design is widely described as premium and distinctive, but the dark chocolate color can divide opinion, and the large earcups create a bold, bulky look on some heads.

Earcup padding is repeatedly described as very plush and supportive, improving seal and comfort, though it can feel warm over extended wear.

Earcup and pad materials are frequently described as plush, premium leather with generous space for larger ears, contributing to both comfort and isolation.

Multiple reviews mention wide swivel/rotation and folding behavior that helps the headphones sit flat, pack smaller, and fit securely into the compact case.

Earcups are commonly described as able to swivel or lay flat, aiding seal and travel storage even though the overall design does not fold compactly.

The 5-band EQ is responsive and helpful for tailoring the signature sound, though it is not as granular as more advanced EQ systems.

Without an app, EQ customization is not available beyond onboard preset modes, which limits personalization compared with mainstream flagship wireless headphones.

Hi-Fi mode is commonly described as balanced and relatively uncolored, while Bass mode shifts the tonality warmer and can slightly reduce upper-mid and treble prominence.

Adjustment and fit mechanisms are practical, with discrete steps and a comfort strap/headband design that helps distribute pressure and maintain a stable seal.

Headband adjustment is described as smooth and secure, holding its position well once set.

Hinges and structure are often described as bendy and durable, but at least one review notes odd twisting behavior when you turn your head.

Included accessories are typically strong for the category: a hard case plus cables for charging and USB-C-to-3.5mm wired listening are commonly noted.

Included accessories are generally considered generous, with multiple cables and adapters plus a premium case, though some note the absence of a USB-C to USB-C cable.

Instrument separation is typically above average with clear placement, but layering can compress or get congested as mixes get busier.

Instrument separation and imaging are consistently praised, with precise placement and clear spacing between layers even in complex mixes.

Reviews that address LDAC note it is not supported, reinforcing that these prioritize battery life and simplicity over hi-res wireless codecs.

At higher volumes, many report clean playback with little obvious distortion, though a few note dynamic compression or a ceiling that flattens crescendos.

Reviews that discuss loud listening report strong composure and minimal distortion at higher volumes, encouraging careful use because it stays clean as you turn it up.

Noise handling on calls is a relative strength, with several tests showing good wind and background-noise suppression, though a few note it can still struggle in very noisy offices.

Call quality ranges from clear in quiet environments to merely decent in louder settings; it is generally usable for everyday calls but not always meeting-grade.

Midrange is generally strong for guitars and vocals, though some note either a slight mid dip (snare/vocals) or occasional mid-forward congestion on busy tracks.

Midrange clarity is repeatedly highlighted as a standout strength, with clean layering and realistic vocal and instrument textures that feel unusually hi-fi for Bluetooth.

Multipoint is widely reported to work well for two devices, though some wish for a device-management list and note occasional confusion when mixing wired and Bluetooth sources.

Multipoint is noted as supported and convenient for staying connected to two devices, though it is not heavily stress-tested across all sources.

Passive isolation is strong thanks to a very good seal from the pads, helping block higher-frequency noise even before ANC is enabled.

Passive noise isolation is described as strong thanks to large, well-sealing earcups and design details aimed at closing gaps around the ear, providing a solid foundation before ANC is even enabled.

Portability is excellent: the cups swivel/fold and the headphones collapse into a very compact shape that fits a small travel case.

Portability is a recurring compromise: the headphones are large, do not fold down compactly, and several reviewers mention the case is too big for many backpacks.

Preset EQ profiles are useful and easy to swap, with bass-boost and other tonal shifts helping different genres, though a few reviewers find boosts could go further.

Preset sound modes are generally seen as well-judged: Hi-Fi is the reference setting for balance and clarity, while Bass mode adds punch and warmth, sometimes with a tradeoff in treble and mid presence.

Replaceable earpads are a strong point, with twist-off pads that are easy to remove and swap, supporting long-term maintenance.

Replaceable earpads are explicitly mentioned as a welcome premium touch, with pads that can be removed for cleaning or replacement.

Wear detection is available for auto play/pause, but experiences vary from fine to slightly slow or occasionally over-sensitive; it can usually be disabled.

Some coverage notes the absence of wear sensors and similar smart conveniences found on mainstream flagships, reinforcing the IO-12 focus on audio and simplicity over automation.

Setup is straightforward and the app layout is easy to navigate, but some reviewers note missing premium conveniences like adaptive ANC behavior or deeper device management.

Day-to-day operation is described as straightforward because settings are handled on the headphones, but the lack of an app also means limited customization and some sources note manual firmware updating.

Across reviews, sound is lively and engaging with a clear lean toward rock-focused tuning, but it stays enjoyable for many genres once EQ is applied. Wired listening works via USB-C using the included cable and is often described as clean and low-latency, but convenience varies because there is no built-in 3.5mm jack and some report you may need power for wired use.

Across reviews, sound quality is the headline: a speaker-like, highly resolving presentation that many call among the best in wireless closed-backs, with strong imaging and refinement. Wired sound is often described as equal or better in resolution than wireless, with USB-C and 3.5 mm options; passive use is supported, and some recommend listening powered on to benefit from onboard DSP.

Soundstage is decent for a closed-back ANC headphone but not the widest; some tracks can feel narrow or cluttered unless you use the Soundstage processing.

Most reviews describe an unusually open, spacious soundstage for a closed-back wireless headphone, with strong width and credible depth; one reviewer notes it is not stadium-wide but avoids feeling claustrophobic.

Soundstage/spatial processing is a fun extra with adjustable room feel, but most agree it is not true immersive spatial audio and can sound synthetic on some tracks.

Fit stability is generally described as secure with a good seal, but the sizing and overall footprint may feel better suited to average-to-larger heads than very small ones.

Several reviews highlight recycled or sustainability-minded materials, positioning these as more eco-considerate than many direct rivals.

Control surfaces are generally responsive; some coverage mentions touch-style control areas, but overall interaction is described as clicky and deliberate rather than finicky.

Transparency mode is usable and adjustable, but opinions vary: some find it natural and clear, while others notice hiss and weaker reproduction of deeper voices.

Transparency mode is generally described as clear and practical for awareness, without strong criticism, though fewer reviews go deep on its nuance.

Treble is crisp and energetic, yet several reviews mention brightness, sibilance, or fatigue on higher notes unless you tame it with EQ.

Treble is generally airy, detailed, and smooth, with occasional notes that it can approach brightness on certain recordings; Bass mode can tame the top end if needed.

USB-C is the single physical port for charging and wired audio, which keeps things simple but also means no dedicated 3.5mm jack.

USB-C is highlighted as both a charging and playback option, with multiple sources noting USB audio support up to 24-bit and 96kHz.

Voice assistant access is supported through the customizable button and app settings, making it easy to trigger assistants or shortcuts without touching your phone.

Voice assistant support is described as available via a press or long-press action, and some sources also mention voice prompts for battery status.

The headphones get loud without needing extreme volume, with multiple reviewers noting comfortable listening well below 100% volume.

Volume output is commonly described as having plenty of headroom, with enough drive to get loud without feeling strained.

There is no stated water or sweat resistance rating in the reviews, so these are best kept away from rain and workouts.

Weight is consistently called light for the class (around the mid-200g range), contributing strongly to comfort and portability.

Weight is noted as present but generally not burdensome once worn, though some acknowledge the overall heft and size compared to mainstream travel headphones.