Zen M650-GM | MOST 50 Network Preamp

The ZEN M650-GM is the most important element in any GM MOST 50 vehicle sound-system upgrade. It has been even been installed in sound-quality competition systems, and won world championships!

The M650-GM provides pure, clean stereo audio - it eliminates all OEM crossover filters, fixed and dynamic EQ, phase manipulation, compression, etc. It is both a high-quality digital-to-analog converter and an audiophile analog preamp - the OEM analog signal path is eliminated. In home-audio terms, the M650-GM is an external D/A converter and an audiophile preamp, connected to the OEM infotainment system with a proprietary digital network. For more on networked preamps, see this Knowledgebase article. 

Any Automatic Noise Cancelling systems are automatically disabled (if present), as is any "fake exhaust" note injected into the sound signal. 

The M650-GM has both high-definition analog RCA and digital SPDIF outputs.  

The Zen M650-GM networked preamp is compatible with many GM vehicles with MOST 50 infotainment networks and Bose sound packages (see Vehicle Compatibility below). 

INPUT
Digital Input - MOST 50 UTP

OUTPUT
Six analog RCA channels (2.1V RMS)
Front Left/Right
Rear Left/Right
Mono Subwoofer
5.1 Center (optional)
S/N Ratio (analog): 112dB
THD+N @ -1dBFS -93dB

POWER SUPPLY
Current Consumption:
Standby: <1 mA
Operational: 350 mA maximum
Operational Voltage: 7V – 20V DC
Remote Turn On Capacity: 500mA

OTHER
Dimensions (module): 4”x5”x1 3/8”
Weight (module)    10 oz
Country of Origin USA
 

Note: The vehicle model year is not always the same as the year of the vehicle's date of manufacture. If you are unclear on the official model year, use the official NHTSA VIN lookup tool here.

The M650-GM includes the following in the package:

• M650 main module (NTV ASY-264)
• Plug-and-Play Integration T-harness (NTV HAR-310)
• USB A to USB Mini A (NTV CAB-009 or equivalent)

Product Manual

NTV_M650-GM_Manual_Rev_A.pdf

How many channels does the Zen M650-GM have? 

This network preamp has six analog RCA outputs, one stereo TOSLINK SPDIF output, and one SPDIF coaxial output. The SPDIF outputs require a third-party device with a compatible SPDIF input and D/A conversion. 

What makes this preamp sound so good?

Some of that is the Zen Audio network preamp technology (more on that here), and some of it is the audiophile-grade D/A converters and op-amps used in the signal path. This preamp was part of a world-champion award-winning sound system!

Does it work in all GM? 

It works in specific GM vehicles that use the MOST 50 infotainment network technology. Please see the Vehicle Compatibility tab for specific coverage information.

See the installation manual for more information. 

You may cancel your order without penalty prior to the product shipping.

Products cancelled or refused after the product has shipped will incur shipping and handling charges as well as a 20% restocking fee.

We will accept returns of eligible items within 30 days of your receipt. Exchanges are also accepted during the 30-day window, and may occur at Nav-TV’s discretion during the warranty period. Products returned within the first 30 days after purchase ,and are subject to a 20% restocking fee. Products must be new, unused and in their original packaging to qualify for a refund.

Please visit the Nav-TV or Zen audio website to start a return or exchange. The order number provided in your confirmation email is required in order to process the return.  

If you believe you have received a defective product, please contact Technical Support to initiate an exchange. Technical Support will work with you to determine next steps. Upon our receipt of the product and confirmation of defect as determined by our inspection, we will provide an exchange unit. Please see our Warranty policy here.

Returned product must be in new and unused condition. The order number provided in your confirmation email is required in order to process the return. Any shipping and handling fees will not be refunded.  You will be responsible for return shipping costs. Upon our receipt of the product in unused/resalable condition as determined by our inspection, we will issue a refund to the credit method used to make the purchase.

The privacy policy can be viewed here.