Asked — Edited

Sound Servo And Leds

Hello everybody, been awhile since I posted.

I'm not home so I cant try this out. Do you think it is possible to have an LED connected to a digital port with Sound servo connected to this port, then as the channel is activated by voice/sound, that changes the brightness of the LED? Is PWM better for LEDs? But there is no Sound PWM command :/ ...yet?!

Also how do I change the "input" for sound servo from mic-in to say a .wav on sound board or mp3 trigger?

Thanks in advance.

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I tested it with a basic red LED rated for about 3v and a resistor of 120 ohm (to match the estimated 5v max PWM output. Connected the LED between the Signal and Ground pins.

It does flash brighter (although rarely to full brightness) in accordance to the volume detected with SoundServo... but it also never goes completely out. You will need to play around with the Update Speed & Scalar settings to your own preference.

As for your 2nd question, no hard and fast answers from me, but that would be a possible sound card feature or software redirect issue within Windows.


Thanks Gunner. I will try it out when I get back to the house in a few weeks. I did a little research last night and it seems there are some simple LED projects out there that will use sound input for LED brightness, so I might go that route. But always nice to go straight from the EZ board. I am working on rapid prototyping an android head and want the LEDs in the eyes to vary in brightness to match his speech and jaw movement.


Check out @bret.tallent's B9 build... he did something similar and you will get some good pointers around this point of his thread. And some updates a little further on.


I made a change to the sound servo control... I think it'll help you. It'll be in the next release:)


Ohhhhh I can't wait! Yay!