Master & Dynamic MH40 B1 (Black/Black) + NuForce Icon uDAC-3 (Black)

Premium Foldable Over-Ear Headphone and High-Resolution USB Desktop Headphone Amplifier DAC

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MH40 B1 Premium Over-Ear Headphones

The Master & Dynamic MH40 B1 Foldable On-Ear Headphone Offer an Incredible Listening Experience

The MH40 B1 Foldable On-Ear Headphone from Master & Dynamic features a 45 mm neodymium high-performance driver. It is constructed with heavy-grain premium cowhide on the headband exterior surface and earcup insets, and soft lambskin on the headband interior and earpads. Designed for mobile use, it features stainless-steel components in all its high-strain areas.

The Master & Dynamic MH40 B1 Foldable On-Ear Headphone Offer an Incredible Listening Experience

The remote and mic are supported only by iPhone 3GS or later, iPad, iPod touch (2nd generation or later), iPod classic (120GB, 160GB), and iPod nano (4th generation or later), remote alone supported by iPod shuffle (3rd generation or later); audio supported by all iPad and iPod models.

The Master & Dynamic MH40 B1 Foldable On-Ear Headphone Offer an Incredible Listening Experience
The Master & Dynamic MH40 B1 Foldable On-Ear Headphone Offer an Incredible Listening Experience

The Modern Thinking Cap

Designed for decades of use, our headphones are built with only the finest materials and tuned to provide a rich, warm sound.

The Best Just Got Better: NuForce UDAC-3

The NuForce UDAC-3) Offer an Incredible Listening Experience

The NuForce uDAC-3 is the answer to all Audiophile hopes and dreams. If you consider yourself to be an Audiophile, Headphone Guru, Music Enthusiast, or Audio Guru, then this is the item for you. Designed as an upgraded replacement to the best selling predecessor uDAC-2, the NuForce uDAC-3 will blow your mind. This 3rd generation uDAC series amplifier has no capacitors within the audio signal path, eliminating any potential distortion. The NuForce uDAC-3 delivers truly superior sound via a high-performance, 24bit/96kHz USB Digital Audio Converter (DAC) and allows you to connect digital audio from your computer to your home stereo, desktop sound system, powered speakers or headphones. Engineered to maximize the performance of any headphone 16 to 300 Ohm, you can now efficiently power your favorite Beyerdynamic, Sennheiser, Grado, Westone, Shure, Audio Technica, Denon, Ultimate Ears, AKG or Sony headphones, and hear what they are truly made of. The NuForce uDAC 3 is guaranteed to impress, and will impress anyone who has the chance to test one for themselves. Built with a compact profile, and an affordable price, everyone deserves that chance!

Master & Dynamic MH40 B1 (Black/Black)

Premium Foldable Over-Ear Headphone
Quantity: 1

General Features:

  • Master & Dynamic MH40B1 Foldable Over-Ear Headphone (Navy/Silver)
  • Heavy grain premium cowhide on headband exterior surface and earcup insets, soft lambskin on headband interior and ear pads
  • Stainless steel components in all high strain areas
  • 45 mm Neodymium High-Performance Drivers
  • Forged Aluminum Body Built for decades of use
  • Heavy duty woven cables oxygen-free copper to ensure pure sound and reduced noise
  • Metal mute button easily accessible: press to mute; press again to unmute
  • Color: Black/Black
  • Authorized Internet Dealer
  • 1-year Manufacturer's Warranty

Product Specifications:

  • Model: MH40
  • Drivers: 45 mm Neodymium
  • Impedance: 32 ohms
  • Weight: 360 g
  • Materials: Cowhide x lambskin leather, stainless steel, aluminum, detachable woven cable
  • Cable: Detachable
    • 1.25m Cable with Remote and Mic
    • 2.00m Standard Cable
  • Headphone Connection: Dual 3.5mm standard jack
  • Ear Coupling: Circum-aural

What's in the Box?

  • Master & Dynamic MH40B1 Foldable Over-Ear Headphone (Black / Black)
  • 3.5/6.3 mm Gold-Plated Adapter
  • 1.25 m Cable with Remote & Mic (iPod, iPad, & iPhone)
  • 2.00 m Standard Cable
  • Canvas Headphone Case
  • Leather Cable Box

NuForce Icon uDAC-3 (Black)

High-Resolution USB Desktop Headphone Amplifier and Digital Audio Converter (DAC)
Quantity: 1

Product Features:

  • Desktop USB DAC
  • Engineered for use with home PC Computers, Laptops, Notebooks, Tablets, MAC or Macbook, Home Stereo System, or many more for Premium Audiophile Grade Sound Performance
  • High-performance 24-bit Resolution and 96kHz Sample Rate for immaculate reproduction
  • USB-Powered, no external power supply required
  • Direct-Stream Digital (DSD) Decoding capability
  • TOCOS Volume Control for precise channel tracking
  • Headphone Amp Circuitry powers headphones with impedance ratings from 16 to 300 Ohms, producing 80mW x 2 channels at 16 Ohms
  • Includes analog RCA, digital coaxial, and 3.5mm outputs for a Variety of Applications
  • Double Jitter-Reduction Mechanism at data level and oversampling filter stages for the best sound quality
  • 2V Analog output
  • Coaxial S/PDIF output
  • No Capacitors In Any of the Signal Paths to reduce and prevent signal tarnish
  • Color: Black
  • Manufacturer Part Number: NF-UDAC3-BLK
  • Also Found As: NuForce U-DAC 3 Black, U-DAC3, NF-UDAC3-BLACK, uDAC-3 BLK, NF-ICON-UDAC3-BLK
  • Also available in Silver (NF-UDAC3-SVR) , and Red (NF-UDAC3-RED

Technical Specifications:

  • Input: USB Digital (1.1 and 2.0 compatible)
  • Native Bit Rate: 32, 44.1, 48, 88.2, 96 kHz, 24-bit
  • Output: Analog RCA output = 2Vrms
  • Dynamic Range: 90 dB
  • Signal-to-Noise Ratio (SNR): 98 dB
  • Total Harmonic Distortion (THD): 0.05%
  • Digital Output: coaxial RCA 75-ohms
  • 3.5mm Output Power: 80mW x 2 @ 16-Ohm
  • Frequency Response: 20 - 20,000 Hz
  • USB Bus Powered, 80 mA/5V
  • Maximum Power Consumption: 500mW
  • Dimensions: 2-11/16"W x 1-1/2"D x 53/64"H
  • Authorized Internet Dealer
  • 1-year Manufacturer's Warranty

What's in the Box?

  • NuForce uDAC-3 (Black)
  • USB Cable (3.3 Feet)
  • Owners Manual
  • Warranty Information

Headphone Design

Headphone Type

This is the design of the earpieces on the headphones. Some headphones go inside the ear, while others rest on the outside of the ear. This helps you know exactly what type of headphones you will be receiving.

In-Ear: The ear buds go into the ear. Most often, the right and left ear buds are two separate pieces.

Enclosed-Ear: Usually are found on the larger headphones. They rest on top of the ear and have padding for comfort, as well as enclosing the ear to the speaker. This type of headphone helps to filter out surrounding noise.

On-Ear: This type of headphone involves the speaker sitting gently on the ear without going in the ear or sealing it off.

Headband Type

Headphone type refers to the construction of the headphones.

Around the Ear means that the headphones wrap around the ear to provide a secure fit. This is most often seen in active and sports headphones.

Around the Neck means that the headphones wrap around the neck. This is also seen in active and sports headphones.

Earbuds means that the right and left sides of the headphones are separated and will fit securely into the ear. These are small, compact, and user friendly.

Over the Head headphones mean that the right and left speakers are connected with a support that goes over the head and rests on top. This is the typical headphone type.

Over the Head
Specifically For
Some headphones can use an IR Transmitter in your vehicle, while some can be plugged into your media device and be used on the go or at home.
Headphone Application

This is the application that the headphones are designed for. Each application has unique features that make it perfect for particular uses.

DJ: These headphones are durable, loud, and will often allow for one ear listening.

Gaming Delivers explosive sound and allows you to communicate with others.

Home Hi-Fi: These audiophile headphones are engineered to produce high fidelity and accurate audio.

Home/Office: These headphones are designed to produce rich, brilliant sounds that the artists would appreciate.

Sports: Designed for active use. These headphones are made to stay in (or on) the ear during workouts.

Kids: Feature noise limiting technology so that your little ones don't damage their ears listening to music too loud.

On-the-Go: On-the-go headphones are lightweight and often fold up for easy storage and portability.

Student: Compact and rugged enough to survive life in a backpack; inexpensive enough to not hurt the wallet of a student.

Studio: Reproduce music perfectly without any coloration. Look here for reference quality studio monitoring headphones.

Traveler/Airplane: These headphones are compact, lightweight, and have a portable design.

Home Hi-Fi
TV & Movie
Acoustic Principle

The basic design of the headphones. There are 3 different types:

Open: Have ports that allow air through the back of the diaphragms, enabling the headphones to sound like the music is coming from an outside source.

Closed: Completely sealed and have no air passing through the diaphragms. Sounds like you are in a closed off room.

Semi-open: Have slots or ports in the back of the cup and are partially open. This allows for a mixed sound between an open and closed headphone.


General Features

Noise Reduction technology removes unwanted noise from a signal. Background or ambient noise can be removed to produce clearer speech and enhanced hearing. Typically these Active Noise Canceling (ANC) headphones are powered and use batteries to activate the noise canceling technology. Also referred to as Noise Reduction or Noise Cancellation.
Device Controls & Compatibility
Refers to the devices the in-line controls are compatible with.
Apple 3 Button (Volume, Track Up/Down, Play/Pause)
Built-In Microphone
This means that the headphones or earbuds have a built-in microphone. This can be a microphone on the cord, built into the headphone, or even a boom microphone. These mics can be used for music devices like iPods, for Smartphones to make and receive calls, or for gaming purposes.
This means the sound of these headphones can be customized to your listening preference through either an app or on-board controls.
Headphone Connection
This is how the headphones connect to the audio source.

Corded means that the headphones use a cord to transfer the audio signal.

Bluetooth means that the audio signal is transmitted from your device to the headphones via a Bluetooth connection.

Corded or Bluetooth means that the headphones can be used as corded headphones or as Bluetooth headphones. They have an input in one or both earcups for use as a corded headphone while they also have a built-in battery for use as Bluetooth wireless headphones.

Wireless means that the audio signal is transmitted wirelessly to the headphones.

Volume Adjustment
Volume Adjustment means that the headphone (independent of the source) can adjust the playback volume. Many headphones and ear buds have in-line volume control, which allows adjusting the audible volume from a switch on the headphones cord. Other headphones have a volume knob on the headphone can.
Connector Type
The type of connection the headphones use to connect to receive the audio signal from a music source. Traditional headphones use an analog 3.5mm headphone jack. Newer technology has allowed digital signals to be sent directly to the headphone using an Apple Lightning or USB-C cable.
Jack Angle

The Jack Angle refers to the angle of the input jack on the headphone cable.

Straight Jack: Straight plug with no angle.

Angled Jack: Angled plug, usually a 90 degree angle.

Swivel Jack: A swivel jack is able to swivel between a straight plug and an angled plug.

Straight Jack
Included Adapters
Refers to the connection adapters included with the headphones like 3.5mm or 1/4" input adapter as well as airplane adapters that let you use your headphones with airplane specific headphone jacks.
1/4" Adapter
Detachable Cable
Refers to whether the cable can detach from the headphones. If a pair of headphones has a detachable cable, the cable can be replaced with a longer cable, one with (or without) a microphone or if you accidentally damage the cable.
Color Shades
Primary color shades of the headphones.
Refers to materials used to build the headphones. Most headphones are built from some combination of plastic and metal to give you a durable pair of headphones.
Ear Cushion/Earbud Material
Refers to the material that the ear cushions/earbuds are made from. Ear cushions and earbuds are available in a variety of materials, ranging from basic rubber eartips to plush leather ear cushions intended for maximum comfort.
Replaceable Ear Cushions
Refers to whether the ear cushions can be removed and replaced. Often times on heavily used headphones, the ear pads can wear out long before the actual headphones. Headphones with replaceable earpads often last much longer than headphones without replaceable earpads.
Protective Case
Refers to whether a pair of headphones come with a protective case.
Softshell Case
Water Resistant
This refers to the level of water resistance of the fitness tracker. Some fitness trackers are water resistant and can be used while swimming, while others are only splash proof or should not be used near the water.
Child Safe
Refers to whether a pair of headphones are designed specifically for children. Child safe headphones feature volume limiting technology so that your child can’t damage their ears while listening to music.
Refers to whether a pair of headphones can be folded up. These headphones feature hinges in the frame above the earcups that allow the headphones to neatly fold into a much more manageable size. Folding headphones are perfect for anyone who spends a lot of time traveling and needs a compact pair of headphones that can fit in their bags.

Audio Features

Driver Type

The physical design of the driver in the headphones.

Balanced Armature:
A balanced armature driver uses a coil wrapped around an armature which is held in between two magnets until it is stimulated by an electrical current. When stimulated, this armature is magnetized which causes it to rotate one way or the other around a pivot point which moves the diaphragm to create sound. Balanced armature driver headphones are generally earbuds and can have multiple drivers in each earbud.

Dynamic drivers are the most common driver type. They feature a permanent magnet, usually neodymium, a voice coil and a conical diaphragm to drive your music. A dynamic headphone driver looks pretty much identical to any typical home theater speaker.

Electrostatic drivers are made up of an extremely thin membrane, usually a coated PET film, stretched between two metal plates. An electrical signal is applied to the metal plates to create an electrical field which, depending on its polarity, draws the speaker diaphragm toward one of the plates which forces air through the perforations in the diaphragm which generates the sound wave.

Planar Magnetic:
A planar magnetic driver is made up of a large membrane suspended between two sets of oppositely aligned magnets. An electric charge is applied to the membrane to induce movement and produce sound waves.

The opposition to electric current, a higher impedance means a higher electrical resistance. This is measured in ohms.
32 ohms
Audiophile headphones represent some of the finest headphones available. Audiophile headphones produce genuinely outstanding sound quality as well as extraordinary build quality, components and comfort. They are truly the finest headphones available.
Built-in Amplifier
This refers to whether the headphones have an amplifier built-in.
Amplifier Recommended
This refers to whether a separate headphone amplifier is recommended for use with a specific pair of headphones. It is highly recommended that any headphone with an impedance greater than 100 ohms be amplified.
Pass Throughs
Refers to whether a pair of headphones has an output to connect to another pair of headphones.

What is in the Box?

Main Product
The main product in the box.
Master & Dynamic MH40 B1
Accessories included with the headphones
1/4" Adapter
Carrying Case
Headphone Stand
Secondary Cable
Paperwork included with the product.
User manual
Warranty/Registration card

Warranty and Return Policy

Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider

Summary of Customer Ratings & Reviews

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Sonic Electronix Wiring Guide

Wiring Diagram Legend

Warning: The image depicted shows the resistance change when wiring multiple subwoofer terminals. Please refer to your subwoofer's owner's manual for the proper wiring of its terminals. Sonic Electronix, Inc. is not responsible for damage caused to your audio system or vehicle due to improper installation. Please call tech support at 1-877-289-7664 if you require additional assistance.

Product Name: Master & Dynamic MH40 B1 (Black/Black) + NuForce Icon uDAC-3 (Black)

  • Differences Between Headphone Acoustic Principles | Open, Closed, & Semi-Open
  • Headphones Based on Musical Preference | What Type of Listener Are You?

Item Added to Cart

Master & Dynamic MH40 B1 (Black/Black) + NuForce Icon uDAC-3 (Black)

Premium Foldable Over-Ear Headphone and High-Resolution USB Desktop Headphone Amplifier DAC


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