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

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.

Qa
iceng6 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
pbergeronronronron (author)  iceng6 years ago
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
basically it doesnt have to be much precise and something analog would do the job
So you only want to listen to the beat ??
Then look up or buy a copy of Walt Jung on filters.

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Kiteman6 years ago
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/