I'm working on using a 28X1 to control a bunch of LEDs for a rave toy. Hence I want these LEDs to be sound-responsive. So I built the sound detection circuit as described at:
www.rev-ed.co.uk/docs/picaxe_sound.pdf
Changed the holding capacitor C4 to a much smaller value (470nF to 22nF) so that the output voltage is only held for a few tens of milliseconds, code up a volume bar graph in software, running 8 LEDs on a breadboard. All well and good, it looks pretty and that's what I'm aiming for.
However, two questions:
1) The minimum sensitivity is pretty poor. The sound level has to be pretty high before the circuit registers anything, even with the sensitivity of RV1 set to a maximum. This is okay if you're just wanting to trigger something with a clap, but I'm keen to have this respond to music without being jammed up against the speaker.
What could be done to make circuit more sensitive?
2) The volume range is pretty poor. I want this to be able to cope with a range of music volumes, from quiet to apocalyptic. Changing the RV1 trimpot does this, but requires fiddling with it.
Has anyone used a digital potentiometer so that the Picaxe can adjust the sensitivity to match the ambient volume range of the music? Did this work and do you have any tips?
Thanks in advance for any help.
www.rev-ed.co.uk/docs/picaxe_sound.pdf
Changed the holding capacitor C4 to a much smaller value (470nF to 22nF) so that the output voltage is only held for a few tens of milliseconds, code up a volume bar graph in software, running 8 LEDs on a breadboard. All well and good, it looks pretty and that's what I'm aiming for.
However, two questions:
1) The minimum sensitivity is pretty poor. The sound level has to be pretty high before the circuit registers anything, even with the sensitivity of RV1 set to a maximum. This is okay if you're just wanting to trigger something with a clap, but I'm keen to have this respond to music without being jammed up against the speaker.
What could be done to make circuit more sensitive?
2) The volume range is pretty poor. I want this to be able to cope with a range of music volumes, from quiet to apocalyptic. Changing the RV1 trimpot does this, but requires fiddling with it.
Has anyone used a digital potentiometer so that the Picaxe can adjust the sensitivity to match the ambient volume range of the music? Did this work and do you have any tips?
Thanks in advance for any help.