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VAREX Smart Box Bluetooth Variable Exhaust Controller
Why the VAREX Smartbox?
The acclaimed VAREX Exhaust System was invented by XForce Performance Exhaust - it has been the most popular choice amongst enthusiasts who are seeking flexible control of their sound level. The VAREX exhaust system allows users to adjust the exhaust sound from stock-car-quiet to sports-car-growl with a click of a key fob button. We love our VAREX exhaust and prefer to keep it in ‘open mode’. However, there are always moments when the high volume exhaust is less desirable.
Imagine the following scenario:
You’re cruising along a country road, tapping on the throttle pedal to maintain cruising speed, (or perhaps letting the cruise control take over). Presumably, you’d hear a low-pitch or loud-humming sound inside the cabin. Some might be fine with that but for many, it’s too much to bear. With a Varex muffler installed, you could reach for the remote key fob to reduce the sound. It’s a good way to go yet not the most convenient.what if we can create a device that will know when and how to change the exhaust sound for us, and do it precisely and automatically?”
Our goal was to make the most user-friendly Variable Exhaust System and reduce the stress of owning a loud performance exhaust. With VAREX Smart Box, we believe we’ve achieved our goal. This smart control system can sense the right moment, and produce the right exhaust sound for your enjoyment. Gladly, our R&D team took up the challenge, and that’s how the idea of Varex Smart Box Bluetooth® Exhaust Controller (VSBec) was created.
What is the Smart Box?
Varex Smart Box is a control device with patent-pending technology that lets the user manually and automatically adjust the exhaust sound level of the Varex exhaust. Users can operate and make changes to the settings via an elegantly designed Smartphone App. The connections between the Smart Boxes and smartphones are via the latest Bluetooth® technology, which provides a intuitive user experience.
Smart Box provides the following functions:
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Manual Mode:
- Precise manual adjustment of VAREX exhaust valve positions;
- Custom pre-set of VAREX exhaust valve position
MATRIX MODE (ONLY WORKS WITH VEHICLES EQUIPPED WITH OBD-II):
- Automatic control of VAREX exhaust valve positions based on real-time information of RPM, throttle and speed.
GEO MODE:
- Automatic control of VAREX exhaust valve positions based on the real-time location of the vehicle.
What is Manual Mode?
Previously the variable exhaust valve of the VAREX muffler was controlled by a key fob, something similar to a car door key fob. When the user presses the button, the exhaust valve will start turning until the pressing is stopped. The key fobs work well but not perfectly. Users aren’t able to precisely control the valve position, and there is no feedback display of what the valve position is. Furthermore, there is no memory for any pre-set valve positions.
The need for more user control of VAREX has been driving our team to design the most user-friendly device by far, which is the “Manual Mode” of Smart Box. By Manual Mode, you can select the 5 pre-set valve positions, which are default to be “Closed”, “25%”,”50%”,”75%”, and “Open”. It’s already a huge step forward, however, we weren’t going to stop there.
We went on to design a procedure to let our users set those pre-set valve positions by simply holding one of the preset buttons, where a custom setting page flips out for picking the desired valve position, and the newly set position will be recorded.
How easy and convenient will that be for all of our customers?
Also, for users who want the touch and feel of the old key fob, we have something for you too! There are two arrow buttons on the bottom of the screen, which imitate the old key fob button operations. Now you can see the turning progress displayed on the Smartphone screen to indicate what the valve position is. We have to say, the operation of the valve position progress circle is such a pleasure to look at!
There’s good news for customers who want to use the existing Varex key fob. The new Smart Box can be connected to the existing key fob controller, and users can operate the Varex muffler. The user can watch the Valve operation progress on the smartphone App whilst operating. The guesswork from the old days is gone and you’ll always know what Valve position it’s at.
We hope you enjoy the brand new experience of the Smart Box Manual Mode. See more information about Manual Mode in the App User Guide.
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What is Matrix Mode?
In order to change the sound automatically, we need to know how to locate the sound. We had a breakthrough in our research which intrigued us. We can locate the sound by three vehicle parameter value ranges: Engine RPM, Throttle Position and Speed.
Based on this finding, we created the “Matrix Mode”. We call the parameter’s value range the “Band”. On the Smartphone app, we have designed a user-friendly interface to pick the right band value. Don’t worry, we’ll show you how this works in the App User Guide section. However, It’s a big task for users to know what “Band value” should be assigned.
We have just the solution! We call it the “Band Snap” feature. (It’s simple to use, even though it requires assistance from a fellow passenger). The user can drive the car as usual and at the moment the exhaust sound we want to find becomes prominent, the driver can instruct the assistant passenger to tap the “Band Snap” button within the App, the Smart Box will automatically assign a band value range for each parameter. Users can even further fine-tune the band range later if needed. Isn’t that magical? Matrix Mode enables our users to easily locate and change exhaust sounds, and do it effortlessly!
NOTE: MATRIX MODE ONLY WORKS WITH A VEHICLE EQUIPPED WITH OBD-II PORT.
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What is Geo Mode?
There are some locations we want the Varex exhaust to be less noisy, while we don’t mind it being loud everywhere else. We believe this is what the Smart Box is supposed to do and we created the GEO Mode specifically for Smart Box.
We want our users to define a region on the map and set a particular exhaust sound for that location. We want it to be done simply and intuitively by dragging a circle on the smartphone screen. And it actually works perfectly! Multiple regions are allowed to be set and memorized. Please see the App User Guide for further instructions.
Finally, you can go home quietly with a Smart Box.


What is in the package?
- Smart Box Control Module x 1
- OBD-II Cable x 1
- GPS External Antenna x 1