PSB M4U 9 Premium Wireless ANC Headphones at Vinyl Sound Toronto Canada

The M4U 9 is a premium wireless active noise-cancelling over-ear headphone from PSB Speakers (Pickering, Ontario, Canada), available at Vinyl Sound in Toronto, Canada. The flagship of PSB's M4U headphone line and the fourth generation of an award-winning wireless ANC platform, the M4U 9 combines 40mm graphene-infused dynamic drivers, Qualcomm aptX Adaptive Bluetooth for up to 24-bit HD wireless audio, and all-digital active noise cancellation via four digital MEMS microphones. Personal Sound by Audiodo calibrates the sonic response independently for each ear, while PSB's proprietary RoomFeel technology reproduces the spatial character of a well-positioned speaker system through the headphone format. Battery runtime reaches 25 hours in Active Mode, with wired operation available via 3.5mm or USB-C connections.

Graphene-Infused Drivers and the PSB True-to-Nature Sound Signature

The driver at the heart of the M4U 9 represents a meaningful step forward from previous M4U generations. A graphene infusion throughout the 40mm dynamic driver cone increases structural stiffness while simultaneously improving damping behaviour, two properties that normally work in opposition in conventional driver materials. Higher stiffness reduces unwanted cone flexion at elevated listening levels, preserving transient accuracy and low-frequency definition. Enhanced damping suppresses resonant ringing at the cone's natural breakup frequency, lowering distortion and contributing to the relaxed, non-fatiguing character that has distinguished PSB speaker designs since Paul Barton began developing loudspeakers at Canada's National Research Council in 1974. The result is a headphone that continues PSB's "True-to-Nature" sonic philosophy, delivering natural timbral balance, controlled bass, and detailed midrange rather than the exaggerated frequency emphasis common in mass-market wireless headphones.

aptX Adaptive Bluetooth, All-Digital ANC, and Voice Technology

The M4U 9 uses Qualcomm's aptX Adaptive Bluetooth codec, which dynamically adjusts its bitrate between 270 kbps and 420 kbps to maintain the best possible audio quality relative to wireless conditions, supporting up to 24-bit HD resolution audio. This represents a significant advancement over the aptX HD codec used in earlier M4U generations and eliminates the fixed-bitrate limitations that affect standard aptX and SBC connections. Active noise cancellation is implemented entirely in the digital domain using four MEMS (Micro-Electro-Mechanical Systems) microphones, a fully digital signal path that reduces the audio conversion errors introduced by analogue-to-digital stages in conventional hybrid ANC systems. Two additional microphones dedicated to Qualcomm's cVc (clear voice capture) technology process call audio independently from the ANC chain, ensuring voice call clarity is maintained even in high-noise environments. NFC tap pairing is supported for compatible devices.

RoomFeel, Audiodo Personal Sound, and the PSB Headphones App

Two personalisation systems work in parallel to adapt the M4U 9's sound to each individual listener. RoomFeel is PSB's proprietary DSP processing mode, developed using acoustic research into room gain — the low-frequency energy reinforcement that room boundaries naturally add to the response of loudspeakers. Applied to the headphone format, RoomFeel recreates the tonal warmth and spatial openness of a well-positioned speaker system, reducing the artificial "in-head" localisation that characterises flat-response headphone tuning. Audiodo Personal Sound adds a second layer of calibration by assessing each ear independently through a series of audio tests and perceptual questions within the PSB Headphones App, generating a custom compensation curve that corrects for individual hearing asymmetries and threshold variations. Four EQ presets, including RoomFeel, Tighter Bass, More Detail, and Better Dialogue, allow further adjustment based on content type. A three-position physical switch on the headphone selects between ANC with RoomFeel, Active with RoomFeel, and Passive modes.

Ergonomic Design for Extended Listening

The M4U 9's earpads are gyro-suspended on pivots that allow each cup to tilt and rotate independently, conforming to a wider range of head geometries than fixed-axis designs. A 15-degree inward tilt angles the driver baffle toward the ear canal, improving acoustic coupling and high-frequency directivity without requiring the listener to tilt their head. Both fabric and leatherette earpad sets are included, allowing users to select the acoustic seal and ventilation characteristics that suit their environment and skin sensitivity. The expandable headband uses a fabric inner cover to reduce pressure points during extended sessions. When battery is depleted, wired operation is available through both a 3.5mm analogue connection and a USB-C digital connection that simultaneously recharges the battery during playback.

Key Features

• 40mm Graphene-Infused Drivers: The dynamic drivers incorporate graphene throughout the cone material, increasing stiffness and damping simultaneously to deliver improved transient accuracy, lower distortion, and the natural tonal balance of PSB's True-to-Nature sound signature.
• Qualcomm aptX Adaptive Bluetooth: Dynamically adjustable bitrate codec supporting up to 24-bit HD wireless audio, providing higher resolution wireless playback than standard aptX or SBC connections.
• All-Digital Active Noise Cancellation: Four digital MEMS microphones feed a fully digital ANC signal chain, eliminating the analogue conversion errors present in conventional ANC systems and delivering clean background noise reduction.
• cVc Clear Voice Capture: Two dedicated microphones with Qualcomm cVc technology process voice calls independently from the ANC chain, maintaining call clarity in high-ambient-noise environments.
• PSB RoomFeel Technology: Proprietary DSP processing recreates the tonal warmth and spatial openness of a speaker system in a well-treated room, reducing in-head localisation and presenting a more natural, open listening experience through the headphone format.
• Audiodo Personal Sound: Independent per-ear hearing calibration via the PSB Headphones App generates a personalised compensation curve that corrects for individual hearing asymmetries across both ears.
• Four EQ Presets: RoomFeel, Tighter Bass, More Detail, and Better Dialogue presets are accessible through the PSB Headphones App for content-specific tuning.
• Three Listening Modes: A physical three-position switch selects between ANC with RoomFeel, Active with RoomFeel, and fully passive operation, giving immediate mode control without requiring the app.
• 25-Hour Battery Life (Active Mode): Extended runtime in active wireless mode covers full travel days and multi-day use without recharging.
• Wired Operation via 3.5mm and USB-C: Dual wired connection options allow passive analogue playback via 3.5mm or powered digital playback and simultaneous battery charging via USB-C.
• Gyro-Suspended Earpads with 15-Degree Tilt: Self-aligning earcup pivots and a 15-degree driver angle optimise acoustic coupling and comfort across a wide range of head shapes for extended wear.
• Fabric and Leatherette Earpads Included: Both earpad materials are supplied, allowing listeners to select their preferred acoustic seal and ventilation characteristics.
• NFC Tap Pairing: Supported for compatible devices for rapid wireless connection without navigating Bluetooth menus.
• PSB Headphones App: Full-featured companion app for iOS and Android manages Audiodo calibration, transparency levels, EQ presets, battery status, and over-the-air firmware updates.

Technical Specifications

Connections at a Glance

• Bluetooth wireless: Qualcomm aptX Adaptive (24-bit HD), NFC tap pairing
• 3.5mm analogue wired input (passive playback)
• USB-C wired input (digital playback and simultaneous battery charging)
• Dual aircraft adapter included for inflight use

What's in the Box

• PSB M4U 9 Wireless ANC Headphones
• Fabric earpads (installed)
• Leatherette earpads
• 3.5mm to 3.5mm analogue cable
• USB-C to USB-A charging cable
• 3.5mm to 6.35mm (1/4") adapter
• Dual-mono aircraft adapter
• Carrying case

Frequently Asked Questions

What are the PSB M4U 9 headphones?

The PSB M4U 9 are premium wireless over-ear active noise-cancelling headphones from PSB Speakers, a Canadian audio brand headquartered in Pickering, Ontario. They use 40mm graphene-infused dynamic drivers, Qualcomm aptX Adaptive Bluetooth for up to 24-bit HD wireless audio, and all-digital ANC via four MEMS microphones. PSB's RoomFeel DSP processing and Audiodo Personal Sound per-ear calibration system personalise the listening experience for each user. Battery runtime is 25 hours in Active Mode, with wired operation available via 3.5mm and USB-C.

How do the PSB M4U 9 compare to the Sony WH-1000XM5 or Bose QuietComfort Ultra as wireless ANC headphones?

The PSB M4U 9, Sony WH-1000XM5, and Bose QuietComfort Ultra each prioritise different aspects of the wireless ANC over-ear category. Sony's XM5 and Bose's QuietComfort Ultra are widely regarded as class leaders for raw ANC depth, particularly against continuous low-frequency noise such as aircraft cabin roar. The PSB M4U 9 differentiates itself through its RoomFeel spatial processing and Audiodo Personal Sound per-ear calibration, which are genuinely audiophile-level personalisation tools not found in either Sony or Bose alternatives. The M4U 9's graphene-infused driver and True-to-Nature tuning philosophy produce a more neutral, natural tonal balance compared to the bass-forward presentation of the Bose and the slightly processed character of the Sony. For listeners who prioritise tonal accuracy and personalised sound calibration over maximum ANC isolation depth, the M4U 9 offers a meaningful point of difference at its price point.

What is aptX Adaptive and why does it matter in the PSB M4U 9?

Qualcomm aptX Adaptive is a next-generation Bluetooth audio codec that dynamically adjusts its transmission bitrate between approximately 270 kbps and 420 kbps based on wireless signal conditions, supporting up to 24-bit high-definition audio resolution. Unlike standard aptX, which operates at a fixed 352 kbps and 16-bit depth, aptX Adaptive maintains the highest available quality under good signal conditions and gracefully reduces bitrate rather than dropping audio quality abruptly when interference occurs. In the PSB M4U 9, aptX Adaptive enables wireless playback of hi-res audio files streamed from compatible devices without the lossy compression artefacts associated with standard Bluetooth audio, making a meaningful difference for listeners playing 24-bit files from services like Qobuz or stored locally on a compatible source device.

What is PSB RoomFeel and how does it work in the M4U 9?

RoomFeel is a proprietary DSP processing mode developed by PSB using acoustic research into room gain — the phenomenon by which room boundary reflections add low-frequency warmth and energy to the response of floor-standing or bookshelf speakers in a real listening environment. In a standard headphone, this room-gain effect is absent, producing a sound that can feel thin, over-detailed, and unnaturally confined to the inside of the head. RoomFeel applies a calculated compensation curve to the headphone's output that reintroduces the tonal character and spatial cues of a well-positioned speaker system, presenting a more natural, open listening experience without exaggerating bass or artificially widening the stereo image. In the M4U 9, RoomFeel is available as a default EQ preset and operates within both ANC and Active listening modes.

Can the PSB M4U 9 be used wired without battery power?

Yes, the PSB M4U 9 supports fully passive wired operation via the 3.5mm analogue connection when the battery is depleted, allowing continued playback from any 3.5mm source device without requiring a charged battery. A 3.5mm to 3.5mm cable and a 3.5mm to 6.35mm adapter are included in the box. USB-C wired operation is also available, but this mode requires some battery power and simultaneously recharges the headphones during playback. The passive 3.5mm mode is the recommended option for situations where battery recharging is not possible, such as during long-haul flights.

Does the PSB M4U 9 work with the PSB Headphones App?

Yes, the PSB Headphones App is the primary interface for accessing the M4U 9's personalisation and configuration features on iOS and Android devices. Through the app, users can run the Audiodo Personal Sound hearing calibration process, adjust transparency mode levels, select from the four EQ presets, check remaining battery level, and receive over-the-air firmware updates. Physical controls on the headphone itself manage volume, playback, call answering, and the three-position listening mode switch without requiring the app, so core functions remain accessible regardless of smartphone availability.

Where can I buy the PSB M4U 9 in Toronto or Canada?

The PSB M4U 9 Premium Wireless ANC Headphones are available at Vinyl Sound in Toronto, Canada. Vinyl Sound is an authorised PSB Speakers dealer serving the Greater Toronto Area and customers across Canada, offering in-store demonstration of the full PSB M4U headphone range alongside the complete PSB speaker lineup. Visit Vinyl Sound in Toronto or shop online at vinylsound.ca to order the M4U 9.