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Looking to get better sound from your iPod® or another player in your car without installing a bunch of new gear? JBL's MS-2 car audio optimizer plugs into your vehicle's power port, then connects between your player and your receiver's auxiliary input. That's it! You'll get better bass, smoother midrange, and sparkling highs — all without changing your receiver or speakers. The MS-2 works for all systems, even those with aftermarket subs installed.

Once connected, simply hold down the "setup" button for a few seconds, and the MS-2 does the rest. Its high-precision digital signal processor takes over, measuring frequency response and calculating the location of your speakers. Then the MS-2 applies timing adjustments and optimizes the audio signal, effectively raising your soundstage to ear level. The sound is now tailored to your vehicle, and you can use the MS-2's bass, treble, and impact controls to fine-tune your sound as needed. The MS-2 remembers the last settings you used, so you won't have to set it up again until you switch vehicles — and the MS-2's simple installation makes it easy to take from car to car.

Product Highlights:

  • plugs in between your portable player and your receiver's auxiliary input
  • automatically analyzes and tailors the sound to your specific vehicle
  • raises soundstage to ear level
  • works with or without aftermarket subs
  • records the last settings used to built-in flash memory
  • no installation necessary — plugs into your vehicle's power port
  • warranty: 1 year
  • Our 60-day money-back guarantee

JBL MS-2 Car Audio Optimizer Reviews

Average Customer Review:

3 Reviews

Shouldn't be sold for more than $50.

Written by: Lerone from Brooklyn, NY on November 19, 2011

Crutchfield Customer Review (What's this?)

I purchased this item recently as an intermediate solution to improving my cars audio until I do all of the necessary upgrades to the receiver, speakers, and amp. The product does provide added improvement to you cars factory system. However, the improvement is not universal. I have a wide taste in music and for some songs the MS-2 sounded great, for others it added way too much distortion (this is when the bypass comes in handy). Furthermore, I had an issue with the unit randomly cutting off (or so I thought) and I contacted JBL tech support via email explaining the situation to them. They never responded. I figured out on my own that I could not have my ipod plugged into the usb port of the MS-2 charger while it's playing. That totally defeated the purpose of having a usb port on the charger. For JBL's lack of customer support and the limited improvements that this product provides, I can not recommend it and would give it no stars if that were possible. From this experience, when I do my future audio upgrades I will not have JBL in mind as a company that I'd like to do business with.




Written by: DaveD from New England on October 9, 2011

Crutchfield Customer Review (What's this?)

I bought this unit after a lot of research. The unit works very well and makes a dramatic difference in sound quality. My door speakers are low and tweeters up high on a factory system (also with a factory sub). With the MS-2 off you can distinctly hear a vocal from 4 spots in the car. With the MS-2 on, it is up front and center above the dash. Much of the nasal quality in voices and instruments is simply gone. There is more separation heard in the highs. It does wonders for piano, acoustical guitar, and vocals. After getting used to this unit, shutting it off is a rather unpleasant experience. The drawback is the wires... I already had too many wires with my car charger and my headphone jack, but now I have even more. It becomes a jumbled mess. To me however, the sound quality is worth it. If you are a bass head, you may not like this product. It removes much of the excessive upper bass and boominess (which some like). If clarity is what you want, this is the most bang for the buck product I can think of. You'd normally need to upgrade a whole slew of gear to get the same difference this little device makes. JBL has done a great job. I do wish the unit was a bit smaller and I could just permanently mount it. Unless you move it from car to car, just having it do it's thing once, adjusting it and leaving it alone is the way to go. It needs a hardwire/bracket option.



Fun and inexpensive Digital Sound Processor

Written by: shootingstar from Malibu, California on August 18, 2011

Crutchfield Customer Review (What's this?)

I just purchased the JBL Car Audio Optimizer. While the fact it is not a "built in" is an issue (it looks a bit messy to have all my auxiliary devices on the passenger seat!) the new car optimizer is a must have for audio files who still use the factory stereo. There is a clear audio difference between "factory stereo" sound and the sound through the JBL. The Audio Optimizer deepens the base, eliminates "noise" and punches up the mid and treble range as well. Concerts sound like concerts! I love the new JBL and has revolutionized my factory stereo at the cost of a restaurant dinner!



Hands-on research

What's in the box?

Download owner's manual

  • JBL ProCoustics MS-2
  • 6-volt/cigarette lighter adapter (with attached 33" DC cord)
  • 6' Stereo minijack cable (with a male 3.5mm connector on each end)
  • 3' Stereo minijack cable (with a male 3.5mm connector on each end)
  • Owner's Manual
  • Warranty Card

Product Research



Overview: The JBL ProCoustics MS-2 is a pocket-sized digital processor designed to enhance the listening experience of your portable compressed music through your car stereo system. Instead of connecting your iPod/iPhone or other portable player directly to your car audio system, you can connect it through the MS-2; and enjoy dramatically improved sonic clarity and stereo imaging. The MS-2 uses DSP (digital signal processing) equalization to optimize system performance for the acoustic characteristics of your speakers, electronics, and vehicle interior; and DSP time correction to ensure that all the sounds reach your ears simultaneously, creating a coherent, richly detailed soundscape. Small enough to fit in a shirt pocket and simple enough for even a novice to set up in seconds, the MS-2 will enhance the listening experience of your iPod/iPhone or other portable MP3 player through your car stereo system.

Simple Installation: The MS-2 works with all music players and all car audio systems that include a 1/8" (3.5mm) auxiliary input jack. Simply plug the power adapter into your vehicle's cigarette lighter, and connect the MS-2 between the source player and your car audio system.

One-Button Setup: The JBL MS-2 pocket digital processor couldn't be any easier to set up & use. Simply plug it in, hold it at eye level (approximately 6-8" from your face), and press the 'Setup' button. In about 5 minutes or less, you'll be enjoying your favorite music like never before.

Optimal Sound: The JBL MS-2 uses feedback from a built-in microphone to optimize the signal from your portable player for the best possible sound from your car audio system. It automatically improves tonal balance, increases bass impact & definition, and maximizes sonic clarity & stereo imaging; all with just a push of the 'Setup' button.

DSP Equalization: The MS-2 uses digital signal processing to improve tonal accuracy by automatically compensating for the sonic characteristics of your speakers, electronics, and vehicle interior.

DSP Time Correction: Time correction automatically ensures that the sounds from all speakers arrive at your ears simultaneously, dramatically improving clarity and imaging. For music to be accurately reproduces and seem as though it comes from musicians spread across the dashboard, instead of from only the speaker nearest you, the sound from the left and right speakers must arrive at your ears at exactly the same time. To achieve this, the MS-2 includes digital time correction.

Tone Controls: Individual Bass, Treble, & Impact controls let you fine-tune the sound to suit particular tracks and your personal preferences.

  • Bass: This function boosts the Bass (such as low-frequency sounds from bass guitar and bass drum). Two levels of bass boost are available.
  • Treble: This function increases or decreases the level of the Treble (such as high frequency sounds from cymbals or female vocals).
  • Impact: This function adds Midbass punch to the sound (such as the fullness of drums or the upper frequencies of a bass guitar). The impact setting may also effect the sound of male vocals.

Bass Filter: The MS-2 has a special Bass filter that is designed to protect small speakers from damage that may be caused by reproducing too much bass.

Note: If your car audio system features speakers large enough to reproduce bass, you can get fuller bass response by disengaging the special Bass filter.

Defeat Switch: A defeat switch lets you compare system performance with & without the JBL MS-2.

USB Charging Port: The included vehicle cigarette lighter not only powers the JBL MS-2, but also includes a female USB (type-A) charging port to charge the battery of your connected portable digital audio player. USB charging cable not supplied.


Maximum Audio Signal Input Voltage: 1.3V

MS-2 Power Supply Voltage Requirement: 10.5V-14.4V DC

MS-2 Power Connector Voltage Output: 6V DC @ 100mA

USB Charger Connector Voltage Output: 5V DC @ 500mA

Dimensions: 2.9375" (w) x 0.875" (h) x 5.25" (d)

Weight: 0.2 lbs

Our Product Research Team

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