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Volume Increase
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Volume Increase

by joshstern on Mon Apr 10, 2017 2:33 pm

Has anyone had any luck upping the volume on the Circuit Playground? I'm working with John's freefall deck but the sound output just isn't there.

Is it possible to add an external speaker?

Thanks,
Josh

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Re: Volume Increase

by adafruit_support_mike on Tue Apr 11, 2017 4:24 am

The signal that controls the speaker isn't broken out to the side of the board, so you'd have to use the tone() function with one of the pins that is broken out.

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Re: Volume Increase

by joshstern on Wed Apr 12, 2017 1:40 pm

adafruit_support_mike wrote:The signal that controls the speaker isn't broken out to the side of the board, so you'd have to use the tone() function with one of the pins that is broken out.


Gotcha, thanks Mike!

Thanks,
Josh

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Re: Volume Increase

by ctgreybeard on Tue Feb 13, 2018 12:50 pm

I have this question too and I thought that A0 was driving the amp that drives the speaker on the Express. Am I incorrect in thinking that? And, if A0 is right then would it be feasible to attach a miniature speaker to that pin to get output? There are some really small speakers available on DigiKey that I am looking at. 8 ohms usually.

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Re: Volume Increase

by adafruit_support_mike on Wed Feb 14, 2018 12:40 am

It depends on which board you're using.

The Circuit Playground Classic uses ATmeaga32u4 pin PC6 to control a transistor, and the transistor controls current through the onboard speaker. That's PWM output, often generated by the tone() function.

The Circuit Playground Express uses pin A0 to feed input to a PAM8301 class-D amplifier, and the PAM8301 drives the speaker. A0 is the DAC output, so you can do direct amplitude control with that.

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Re: Volume Increase

by ctgreybeard on Wed Feb 14, 2018 12:57 am

Thanks, Mike. I do have an Express. Do you think it possible that A0 could drive a micro (cell phone) speaker? I'd try it but I don't have one handy. The one on the board is really weak but it is rather small. I have a little more room in my design to fit a 10 or 15 mm speaker in.

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Re: Volume Increase

by adafruit_support_mike on Wed Feb 14, 2018 2:29 am

A0 can't drive a speaker by itself.

Even a tiny speaker uses a few hundred milliamps, and the A0 pin can do maybe 7mA. You'd need to connect the signal to something like a PAM8302 breakout to get a signal strong enough for a speaker:

https://www.adafruit.com/product/2130

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