A question about switching between a speaker and headphones

Hello,

I am working on a small project using sound from an Arduino Pro Mini, through a Sparkfun Mono Audio Amplifier Breakout (https://www.sparkfun.com/products/11044) to a small speaker.

It works just fine.

What I would like to do is add a mono headphone jack and have a choice of choosing, via a switch(?), whether the sound from the audio output of the amp board goes to the headphone jack or the speaker.

Any suggestions would be greatly appreciated. :slight_smile:

Use a SPDT switch.

Example of use:

Hi,

Thank you for taking the time to reply to this super-Newbie question.

I do have an SPDT switch on hand but I am a bit confused with the hookup.

The Audio Amp Breakout has OUT + and - wires which are easy when it is just a speaker being hooked up, + and - go to each of the speaker wires. My confusion is with addition of the headphone jack and switch.

May I ask how you would suggest hooking it all up? I am still in the breadboard stage.

Cheers! :slight_smile:

The (-) connection is the common ground connection that's connected to the speaker and headphone.

FYI - There is something called a "closed circuit" jack. It has a built-in switch that cuts-off the speaker when you plug-in the headphones.

Hello,

Thanks for your reply. I looked up the closed circuit jack, it is a great solution but I am trying to use what I have on hand.

Cheers :slight_smile:

Don't forget to put a 100-200 ohm resistor in series with the headphone output. Otherwise the level will be way too loud for a given speaker volume.

aarg:
Don't forget to put a 100-200 ohm resistor in series with the headphone output. Otherwise the level will be way too loud for a given speaker volume.

Thanks for the tip, a 220 ohm resistor for the headphone output is giving me just the right volume. :slight_smile:

arduinokov:
Thanks for your reply. I looked up the closed circuit jack, it is a great solution but I am trying to use what I have on hand.

It would be rather unusual to have a jack - at least a panel mounted or PCB jack - that does not have the closed circuit pin.

Note the three pins.

Paul__B:
It would be rather unusual to have a jack - at least a panel mounted or PCB jack - that does not have the closed circuit pin.

Thank you Paul for your reply. So I really donโ€™t need a switch. Iโ€™ve got a few of these jacks on hand. How would this be wired? I assume it goes between the Audio input and the speaker?

Cheers!

Thank you for the diagram and many thanks to everyone that helped out, this is the last part of my project that was keeping me from finishing.

Cheers! :slight_smile:

larryd:

What circuit sketching software is that?

WinQcad

Not supported any more but there are a few sites where it can still been downloaded.

Last piece of the project in place, everything is working! :slight_smile: