Engine Sound Analyzer:RPM Calc

Contains ads
2.8
129 reviews
10K+
Downloads
Content rating
Everyone
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About this app

It is an application that estimates the engine Revolutions Per Minute [RPM] from the exhaust noise of a motorcycle or car when idling. By all means for maintenance of vehicles without tachometers such as scooters !


The idling sound includes the sound of the engine exploding, the rotation of the crankshaft / motor e.t.c., and the sound of various parts.
This application divides the sound measured by the microphone for each frequency and calculates the rotation speed [rpm] from the loudest frequency.
* Measurement results may vary due to various factors such as ambient sound, vehicle type, terminal used, and distance from the sound source. Please treat the measurement result as a reference value. In addition, it may not be possible to measure correctly depending on the model, rotation speed, and microphone performance.


• Set the number of engine strokes and cylinders
• Start measurement with “RUN” or “▷”
• Adjust the Gain and Threshold to place the peak value above the Threshold line
• Select any peak with "<" and ">"
• Stop at “□”
* Measurement will stop when the count is exhausted. You can extend the measurement time by seeing the reward advertisement or restart.


* Never use it while driving. There is a risk of accidents.
* Do not touch the heat source, keep away from it. There is a risk of burns or terminal failure.
* Securely fix the vehicle or machine so that it does not move. It may fall or move suddenly, leading to an unexpected accident.


For a long time, DIY has always liked to maintain motorcycles as a hobby.
When deciding the idling height while thinking "Is it like this?" When repairing an engine malfunction or carburetor in winter, or when adjusting the air screw, ask "Where is the number of revolutions high?" I was setting the settings while feeling. Then I had the opportunity to study the Fourier transform in another case, and if I analyze the engine sound with this, I think it can be quantified. What I thought was interesting was the reason I decided to do DIY.

I hope this app helps someone somewhere in the world.
Updated on
Jan 16, 2024

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
No data shared with third parties
Learn more about how developers declare sharing
This app may collect these data types
Location, App activity and 2 others
Data is encrypted in transit

Ratings and reviews

2.8
127 reviews
Hairy Jon
March 10, 2024
I used this app when installing an aftermarket tachometer. Very accurate. I tested it on my daily driver whilst using and OBD2 real time scanner and it's was very close. Great app. Thanks!
3 people found this review helpful
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b star360
May 1, 2024
Seems to be very good for 4 stroke multi cylinder, but I'm having problems with single cylinder 2 stroke motorcycle. Maybe I'm not using the app properly.
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Rick Cottle
February 19, 2024
Don't want to be negative but it indicates 23000 rpm when my bike is idleing .. it's not as accurate as I,d like. Tried jiggling all the settings and never came close to reality.
2 people found this review helpful
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What's new

*Fixed a bug where HPF and LPF were not functioning.
*Reviewed the count of rewards obtained through reward advertisements.
*Implemented GDPR compliance.