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 CAB009 or equivalent)

Product Manual

Download the product manual here. 

Using the M650-GM Preamp

Use Case 1 - Full-Range Analog RCA to Aftermarket Gear
 

NOTE: RCA #6, 5.1 Center, is only active when playing 5.1 sources with discrete center-channel content in OEM systems which support it. It is NOT a upmixed output!

NOTE: Subwoofer Level can be controlled via the head unit’s bass tone control - see DIP SWITCHES, P. 13 of the manual. 

NOTE: The blue wire will output 12V(+) when a door is unlocked or opened.
 

Use Case 2 - Full-Range Toslink Fiber Optic to Aftermarket Gear

NOTE: Head Unit Front/Rear Fade function and Subwoofer Level from Bass Tone Control function are not available with Toslink outputs.

NOTE: The blue wire will output 12V(+) when a door is unlocked or opened. 

Use Case 3 - Full-Range SPDIF Coaxial to Aftermarket Gear

NOTE: Head Unit Front/Rear Fade function and Subwoofer Level from Bass Tone Control function are not available with SPDIF outputs.
 

NOTE: The blue wire will output 12V(+) when a door is unlocked or opened.

Use Case 4 - Add-A-Sub

NOTE: Subwoofer Level can be controlled via the head unit’s bass tone control - see DIP SWITCHES, P. 13 of the manual. 

NOTE: The blue wire will output 12V(+) when a door is unlocked or opened.

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.

Privacy Policy

This privacy policy has been compiled to better serve those who are concerned with how their 'Personally identifiable information' (PII) is being used online. PII, as used in US privacy law and information security, is information that can be used on its own or with other information to identify, contact, or locate a single person, or to identify an individual in context. Please read our privacy policy carefully to get a clear understanding of how we collect, use, protect or otherwise handle your Personally Identifiable Information in accordance with our website.
 
What personal information do we collect from the people that visit our blog, website or app?
 
When ordering or registering on our site, as appropriate, you may be asked to enter your name, email address, mailing address, phone number, credit card information or other details to help you with your experience.
 
When do we collect information?
 
We collect information from you when you register on our site, place an order, subscribe to a newsletter, respond to a survey or enter information on our site.
 
How do we use your information?
 
We may use the information we collect from you when you register, make a purchase, sign up for our newsletter, respond to a survey or marketing communication, surf the website, or use certain other site features in the following ways:
     • To personalize user's experience and to allow us to deliver the type of content and product offerings in which you are most interested.
     • To improve our website in order to better serve you.
     • To allow us to better service you in responding to your customer service requests.
     • To administer a contest, promotion, survey or other site feature.
     • To quickly process your transactions.
     • To send periodic emails regarding your order or other products and services.
 
How do we protect visitor information?
 
Our website is scanned on a regular basis for security holes and known vulnerabilities in order to make your visit to our site as safe as possible.

We use regular Malware Scanning.

Your personal information is contained behind secured networks and is only accessible by a limited number of persons who have special access rights to such systems, and are required to keep the information confidential. In addition, all sensitive/credit information you supply is encrypted via Secure Socket Layer (SSL) technology.
 
We implement a variety of security measures when a user places an order enters, submits, or accesses their information to maintain the safety of your personal information.
 
All transactions are processed through a gateway provider and are not stored or processed on our servers.
 
Do we use 'cookies'?
 
Yes. Cookies are small files that a site or its service provider transfers to your computer's hard drive through your Web browser (if you allow) that enables the site's or service provider's systems to recognize your browser and capture and remember certain information. For instance, we use cookies to help us remember and process the items in your shopping cart. They are also used to help us understand your preferences based on previous or current site activity, which enables us to provide you with improved services. We also use cookies to help us compile aggregate data about site traffic and site interaction so that we can offer better site experiences and tools in the future.
We use cookies to:
     • Help remember and process the items in the shopping cart.
     • Understand and save user's preferences for future visits.
     • Compile aggregate data about site traffic and site interactions in order to offer better site experiences and tools in the future. We may also use trusted third party services that track this information on our behalf.
You can choose to have your computer warn you each time a cookie is being sent, or you can choose to turn off all cookies. You do this through your browser (like Internet Explorer) settings. Each browser is a little different, so look at your browser's Help menu to learn the correct way to modify your cookies.
 
If you disable cookies off, some features will be disabled and may affect the users experience that make your site experience more efficient and some of our services will not function properly.
 
However, you can still place orders .
 
Third Party Disclosure
 
We do not sell, trade, or otherwise transfer to outside parties your personally identifiable information.
 
Third party links
 
We do not include or offer third party products or services on our website.
 
Google
 
Google's advertising requirements can be summed up by Google's Advertising Principles. They are put in place to provide a positive experience for users. https://support.google.com/adwordspolicy/answer/1316548?hl=en
We have not enabled Google AdSense on our site but we may do so in the future.
 
California Online Privacy Protection Act
 
CalOPPA is the first state law in the nation to require commercial websites and online services to post a privacy policy. The law's reach stretches well beyond California to require a person or company in the United States (and conceivably the world) that operates websites collecting personally identifiable information from California consumers to post a conspicuous privacy policy on its website stating exactly the information being collected and those individuals with whom it is being shared, and to comply with this policy. - See more at: http://consumercal.org/california-online-privacy-protection-act-caloppa/#sthash.0FdRbT51.dpuf
According to CalOPPA we agree to the following:
Users can visit our site anonymously
Once this privacy policy is created, we will add a link to it on our home page, or as a minimum on the first significant page after entering our website.

Our Privacy Policy link includes the word 'Privacy', and can be easily be found on the page specified above.
Users will be notified of any privacy policy changes:
     • On our Privacy Policy Page

Users are able to change their personal information:
     • By emailing us

How does our site handle do not track signals?
We honor do not track signals and do not track, plant cookies, or use advertising when a Do Not Track (DNT) browser mechanism is in place.
Does our site allow third party behavioral tracking?
It's also important to note that we do not allow third party behavioral tracking
 
COPPA (Children Online Privacy Protection Act)
 
When it comes to the collection of personal information from children under 13, the Children's Online Privacy Protection Act (COPPA) puts parents in control. The Federal Trade Commission, the nation's consumer protection agency, enforces the COPPA Rule, which spells out what operators of websites and online services must do to protect children's privacy and safety online.
We do not specifically market to children under 13.
 
Fair Information Practices
 
The Fair Information Practices Principles form the backbone of privacy law in the United States and the concepts they include have played a significant role in the development of data protection laws around the globe. Understanding the Fair Information Practice Principles and how they should be implemented is critical to comply with the various privacy laws that protect personal information.
In order to be in line with Fair Information Practices we will take the following responsive action, should a data breach occur:
We will notify the users via email
     • Within 7 business days
We will notify the users via in site notification
     • Within 1 business day
We also agree to the individual redress principle, which requires that individuals have a right to pursue legally enforceable rights against data collectors and processors who fail to adhere to the law. This principle requires not only that individuals have enforceable rights against data users, but also that individuals have recourse to courts or a government agency to investigate and/or prosecute non-compliance by data processors.
 
CAN SPAM Act
 
The CAN-SPAM Act is a law that sets the rules for commercial email, establishes requirements for commercial messages, gives recipients the right to have emails stopped from being sent to them, and spells out tough penalties for violations.
We collect your email address in order to:
     • Send information, respond to inquiries, and/or other requests or questions.
     • Process orders and to send information and updates pertaining to orders
     • Market to our mailing list or continue to send emails to our clients after the original transaction has occurred
To be in accordance with CANSPAM we agree to the following:
     • NOT use false, or misleading subjects or email addresses
     • Identify the message as an advertisement in some reasonable way
     • Include the physical address of our business or site headquarters
     • Monitor third party email marketing services for compliance, if one is used.
     • Honor opt-out/unsubscribe requests quickly
     • Allow users to unsubscribe by using the link at the bottom of each email
If at any time you would like to unsubscribe from receiving future emails, you can email us at
     • Follow the instructions at the bottom of each email.
and we will promptly remove you from ALL correspondence.
 
Contacting Us
 
If there are any questions regarding this privacy policy you may contact us using the information below.