Skip to main contentSkip to footer

Explore more like this

Slide 1 of 6

Overview

The Fosi Audio IM4 is a professional-grade hybrid in-ear monitor designed for audiophiles and musicians who demand precision and clarity. At the heart of each monitor is a sophisticated five-driver configuration, combining one 10mm dynamic driver for powerful, rhythmic bass with four specialized balanced armature drivers for transparent mids and crystalline highs. This hybrid architecture ensures that every layer of your music is reproduced with incredible accuracy.

Fosi Audio IM4 Open-Back HiFi In-Ear Monitor Headphones with 10mm Beryllium Drivers

Model: Fosi Audio
Web Code: 19723137
Sold and shipped by | 4.5 seller rating (547 reviews)

Colour: Galaxy Silver

Colour Obsidian Gray
Colour Obsidian Gray

Obsidian Gray

Colour Galaxy Silver
Colour Galaxy Silver

Galaxy Silver

Available for deliveryAvailable online only

Delivery times vary by location. Most Marketplace items leave sellers' locations within 2 business days. Allow additional time for shipping.

Seller Return Policy

Read return policy

Warranty

Check with the manufacturer for details.

For Quebec residents: See the Availability Guarantee disclosure in the Specifications section below.

Crafted with an ergonomic resin shell, the IM4 provides a secure and comfortable fit that naturally isolates external noise, making it ideal for stage monitoring or daily commuting. The included high-purity silver-plated copper cable utilizes a standard 0.78mm 2-pin connection, allowing for easy replacements or high-end cable upgrades. Whether you are a professional performer or a dedicated listener, the Fosi Audio IM4 offers a balanced and detailed sonic performance that brings your high-resolution audio to life.

Five Driver Hybrid Configuration: Combines a 10mm dynamic driver with four balanced armatures to deliver a full-spectrum, high-fidelity sound signature.

Precise Electronic Crossover: Utilizes advanced internal circuitry to ensure a seamless transition between drivers for a coherent and balanced audio profile.

Medical Grade Resin Shell: The skin-friendly, handcrafted resin housing is contoured to the human ear for exceptional long-term comfort and stability.

Superior Passive Noise Isolation: The ergonomic design provides up to 26dB of noise reduction, allowing you to focus on your music in loud environments.

Detachable 2-Pin Cable: Equipped with a high-quality 0.78mm 2-pin silver-plated copper cable for superior signal conductivity and durability.

Professional Tuning for Monitoring: Optimized to provide an accurate and detailed response suitable for critical listening, mixing, and stage use.

High-Resolution Audio Certified: Boasts an extended frequency response from 20Hz to 40kHz to capture the finest details of lossless audio files.

Comprehensive Accessory Kit: Includes multiple sizes of silicone tips and a rugged storage case to ensure the perfect fit and protection for your monitors.

Specifications:

Driver Type: Hybrid (1 Dynamic Driver and 4 Balanced Armatures)

Dynamic Driver Diameter: 10mm

Balanced Armature Configuration: 4 Custom BA Drivers

Frequency Response Range: 20Hz to 40kHz

Sensitivity: 110dB at 1kHz

Nominal Impedance: 24 Ohms

Connector Type: 0.78mm 2-Pin (Detachable)

Plug Termination: 3.5mm Gold-Plated Stereo Jack

Cable Material: Silver-Plated Oxygen-Free Copper (OFC)

Cable Length: 1.2 Meters

Housing Material: Medical Grade Resin

Weight Per Earbud: Approximately 5.5g

For Quebec residents – Disclosure under the Consumer Protection Act

In compliance with Bill 29, Best Buy and third-party sellers on Best Buy Marketplace do not guarantee the availability of replacement parts, repair services, or maintenance information for any products. Coverage provided through any Best Buy Protection programs and applicable manufacturer warranties, if any, remain in place. Please contact the manufacturer directly for information about their availability guarantee.

Shipping Charges

Free standard shipping may be available on orders over a minimum amount (before taxes, fees, and promo codes). Shipping charges may vary based on item size and your shipping address. Want a shipping charge estimate? Simply add an item to your cart, then access the cart and enter your postal code in the shipping estimate section.

Processing Time

Most items ship within 2 business days after an order is placed*. Allow additional time for shipping to your address.
*Please note: If an item you ordered becomes unavailable, you'll be notified and a full refund will be processed within 2 business days.

Shipping Area Restrictions

Shipping is not available in the following areas*:
  • No restrictions in Canada
*Please note: Shipping area restrictions may vary for large items. If an item can't be shipped to your address, we'll let you know during the checkout process.
Product Category
Headphones, earphones, and ear buds (of any kind including AirPods)
Return/Exchange Period
30 days
Condition
Unopened, No signs of use

Due to hygiene concerns, this product cannot be returned if opened

Learn more about returning a Marketplace product