Alpine's state-of-the-art SHS-N251 dual source wireless headphone system gives your passengers the ultimate in convenience and versatility! Connect the audio output of two different A/V sources to the infrared transmitter and two people can listen to separate audio tracks on wireless headphones, free of the tangle of headphone wires — simultaneously!

Each headphone unit has an A/B source selector switch and volume control, so the user has the ability to choose between different audio sources independently. Each headphone unit uses two AAA batteries.

Important Note: The headphones are for passengers use only! Most states prohibit the use of headphones by the driver while operating the vehicle.

  • dual source
  • extended bass driver for enhanced low-end response
  • easy-fit adjustable headband
  • opti-angle dual source infrared transmitter - mount with a clear "line-of-sight" path to the headphones
  • independent source selection
  • auto power off — after a few minutes without a signal source, the headphones automatically power off
  • automatic level control
  • 4 AAA batteries included
  • transmitter dimensions: 3-3/4"W x 4-11/16"D x 2-1/16"H
  • 1-year warranty
Be the first to review this product
Great Gear Giveaway

Submit a review and then enter to win a $350 rewards card

Review this product:

Thanks for taking the time to share your experiences about this product. Please be sure to focus your comments on the product itself. Read our Review Guidelines for more information.

Your email won't be visible. Please use the email address that is associated with your order.
(e.g., JohnD) Your review will be signed using the display name and location
(e.g., Charlottesville, VA)

Click on a star to rate the overall product on a scale of 1-5
1500 characters left
  Attach a YouTube Review
Crutchfield Video Review Guidelines
  • Only submit videos that you made or are authorized to use.
  • Do not submit videos that contain music, video or visuals that are copyrighted and belong to someone else.
  • Please see our Review Guidelines for more information.
500 characters left
500 characters left

Hands-on research

What's in the box?

Download owner's manual

  • Infrared transmitter
  • 2 Pairs SHS-N201 dual-source wireless headphones
  • 4 "AAA" batteries
  • One 7" Power/source connector A (5-pin connector to female stereo RCA jacks and power/ground leads)
  • One 8" Source connector B (3-pin connector to female stereo RCA jacks)
  • 2 Mounting screws
  • 2 Plastic mounting screw covers
  • User's manual
  • Wiring diagram

Product Research

Transmitter Features

Headphone Features


Product Overview: The Alpine SHS-N251 Dual Source Mobile Wireless Headphone System offers vehicle passengers the convenience of privately listening to either of two audio/video sources through the supplied SHS-N201 wireless headphones. The infrared transmitter simultaneously transmits audio from both sources, allowing each headphone user to independently choose which audio source to listen to.

Important Safety Note: This product is designed for use by the vehicle's passengers only! Most states prohibit the use of headphones while operating a vehicle.

Transmitter Features

Opti-Angle Dual Source Infrared Transmitter: The transmitter has a curved face with a 3.5" wide infrared window providing a wide dispersion of the signal throughout the vehicle. Since infrared signals are "line-of-sight," the user should be positioned so there is a clear signal path between the transmitter's infrared window and the headphones. The transmitter has dual inputs and can simultaneously transmit signals from two sources. This allows each headphone user to choose which audio source to listen to.

Transmitter Dimensions: Width: 3.75", Depth: 4.667", Height: 2.025"

Installation: The transmitter is designed to be mounted to the ceiling of the vehicle, in the middle of the seating area, positioned just above the thigh area of the second passenger row seating. It should be mounted so the infrared window faces the rear of the vehicle. Two sets of wires are attached to the transmitter: one with a 5-pin connector for the power and ground leads as well as the Source "A" input, the other with a 3-pin connector for the Source "B" input. The harnesses included with the system plug directly into these connectors. Note: Since the total length of the attached wiring harnesses is only about 12", the user will need to provide two additional RCA patch cords and additional wire to extend the power and ground leads. Two mounting screws and screw covers are included.

Headphone Features

Independent Dual-Source Headphones: The included SHS-N201 stereo headphones each have an A-B switch on the right earcup, allowing the user to independently choose which of the two transmitted audio sources they want to listen to.

Materials: The headphones feature a plastic outer headband with a soft rubber inner headband. The angled earpieces are also plastic and are independently adjustable along the headband for length, but do not swivel. The earcups are foam-covered on-the-ear style. The headphones require 2 "AAA" batteries (included) which can be inserted in the left earpiece.

Easy-Fit, Adjustable Headband: The length of the headband can be adjusted at each earpiece to one of nine positions for maximum comfort and fit.

Extended Bass Drivers (E.B.D): The drivers in the headphones are designed to produce extended bass frequencies for a wider frequency response.

Automatic Level Control: This headphone system has an automatic level control to prevent input signal overloading. This assures the signal is clear and free of distortion and protects the user from unexpected loud bursts of audio through the headphones.

Automatic Power Off: To extend the life of the batteries, the headphones have an automatic power off feature. After a few minutes without a signal source, the power to the headphones will automatically turn itself off.

Controls/Indicators: The headphones have the following controls and indicators:

  • Left Earcup: Power on/off switch, Battery compartment
  • Right Earcup: Source A-B switch, Rotary volume control, Power on LED indicator


  • Outer Headband: Adjustable Length: 12-15", Width: 1.625"
  • Inner Headband: Adjustable Length: 11-13", Width: 1.375"
  • Earcups: Width: 2.675", Height: 3.25", Thickness: 1.5"

Our Product Research Team

At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.