[Andrzej’s] plain old computer speakers are ordinary no more. He pulled off a fairly complicated hack which now lets him control speakers via Bluetooth.
He had a set of Creative brand computer speakers with a volume potentiometer that needed replacing. He was having trouble finding a drop-in replacement part and decided he would just go with a rotary encoder. Obviously you can’t just drop one of those in, he would need a microcontroller to monitor the encoder and translate the change into the appropriate resistance. He figured if he was going this far he might as well make the most out of the uC.
Above you can see all the stuff he crammed into the original case. The rotary encoder is seen on the lower left. An ATmega8 is on a PCB he made himself. The white part to the left is a digital potentiometer which feeds the resistance to the original speaker PCB. On the left is the Bluetooth module which lets him control everything from his phone. You can see a demo of that after the break.
N900, best phone for hacker ever made.
Nice hack,i don’t intend to bash it but converting it to Rotary is rather waste of time and resources for something without value like these speakers,
I would just Motorize the potentiometer and use just a positive and negative voltage signal to control the motor over bluetooth or whatever else… In this case anything other than IR is not worth it unless you want to demonstrate your abilities or just want to play.
You could have kept the original potentiometer’s and fed them into the ADC of the mcu. The input with “priority” is the one most recently changed. Also, for the output stage, cheap audio opto coupler’s would be easier to work with (basically an LED+photocell in one package).
The original potentiometer needed replacing.
Even though something like these speakers might now have little monetary value, they still might have value in some other way that pleases ourselves; Sometimes we just choose to hack them because it’s fun or to make something unique.
Plus if he ever replaces the speaks with a nice system he could easily change this system to control the new one!
thats what i was thinking;
risk to 20$ unit,
then if its good,
drill holes into 200$ unit :)
or make second
now phone control both ;)
Okay I like this… But I want to know if we can do this kind of thing but instead flow music to the HC-05 bluetooth module. So I want it to be PC -> HC-05 -> Speakers. And they will play anything to whoever is connected to it. How could we approach that?