FAQ Frequently Asked Questions

  • Speakers – I might as well get my own.  What are the specifications?

Answer: You can use any types of speaker(s) as long as they handle the power you require.
Here are the integrated amplifier specifications:

Output power @ 12V 1% THD+N 10% THD+N
4 ohm speakers 27W 32W
8 ohm speakers 16W 20W


  • Can I find my own sound recording and download it to the SoundRacer?

Answer: Yes, you need four recordings (or computer generated sounds): Idling, low rpm acceleration, high rpm acceleration and deceleration. Specifications are described in the User Manual. A Windows program for generation of the proprietary .srf file is included with the sound module. 30 parameters controlling the sound generation can be set in the program.


  • You say there is a simulated shifting function – I am using a transmission, so should not have to use it, right?

Answer: That is correct if the sound system reads the motor RPM. If the system reads the vehicle speed it can be used. To activate the simulated shifting an input pin on the sound module has to be grounded with a connected switch.


  • I can use the motor speed encoder?   What is the input resistance of the SR?  I am asking because I don’t want to reduce the signal to the Motor Controller, it is quite weak.

Answer: Available analog or pulsed (frequency) signals from motor controller or speed sensor can be used.
Here are the input specifications:

Inputs Pulsed Analog
Input signal 3,5 – 19V 0 – 3,9V
Input resistance 0V – 4V 110 kohm 22 kohm
Input resistance 4V – TVS 10 kohm 10 kohm
Transient Voltage Suppressor 20V 5V


  • You write the SR can be set so it turns off above a certain speed.  Is there also a manual setting so I can just turn it off and on as required?

Answer: Yes, there are four ways to adjust the sound level:
1. Setting a parameter in the Windows program when generating the .srf file will control at which speed the sound will be muted.
2. Output sound volume can be set with a potentiometer on the module PCB.
3. Volume can be adjusted with an external potentiometer, overriding the internal.
4. Just disconnect power to silence the sound. All settings and sound will be the same when connecting power again and startup is indicated with a short revving.


  • Can the sounds be changed just using the SR, or do I have to connect it to a computer?

Answer: Several sound files are stored on a MicroSD memory card in the module. By grounding an input pin with a connected switch, the next sound is loaded inte the processor and starts playing after a few seconds. Each sound file has its own set of parameters making it easy to test and evaluate different sounds and settings. Generating new sound files to store on the MicroSD card requires a Windows computer.