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need help to make a bpm matching circuit (for music) Answered

i have good knowledge in electronics but i have no clue for this.
i need a circuit that i would input music, and as output would get a bpm (voltage activated(5v) on the beat)
i want to use this to make lights for parties that move on the music, i am not looking for a color organ

anyone have ideas?

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"pbergeronronronron (author) says:
seems more complicated then i thought, i was thinking about something simpler, a low pass filter (to get most of the kick drum) using a diode to get positive only, then amplifing this to get a signal on the beat"

So what you really do want is the bass channel from a 3 band color organ. Check out the search I just gave or search Instructables for one.

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iceng

6 years ago

Getting BPM is more sophisticated then measuring zero crossings.
I can see two ways, both take programming but perform the same functions.
Assuming you know what FQ range represents the beat ;
  1. You make a wide notch pass filter for that FQ range and feed that volume to the ADC input of a uP that begins to look fore slope changes and times the peaks or troughs to calculate the BPMs and sends an ASCII text sequence to a $40 two line LCD describing the continual BPM for reading by you.
  2. Instead of a hardware notch filter, use a DSP to both select the beat volume and the DSP (Digital Signl Processor ) can also measure the timing and drive a small LCDisplay.
A DSP is a much faster more expensive uP.

Hope this helps.

A

seems more complicated then i thought, i was thinking about something simpler, a low pass filter (to get most of the kick drum) using a diode to get positive only, then amplifing this to get a signal on the beat

Have a look at these instructables:

https://www.instructables.com/id/Blinking-LEDs-to-Music/

https://www.instructables.com/id/Musicator-Jr-Mk-2/

https://www.instructables.com/id/Music-Led-Bar/

https://www.instructables.com/id/Music-LED-Light-Box/

https://www.instructables.com/id/Music-Synchronized-Christmas-Lights/