Electronics 2000

Hello, I am about to embark on an electronics project, whereby I will make an electronic musical instrument. The principle is to use a 555 IC and a speaker. Of course, variation in the resistance will alter the frequency. However, I would like to be able to play chords; in other words, I want a single speaker to play two different frequencies simultaneously. Is this possible?

The circuit diagram is based on this: http://www.design-technology.info/ks3/y8/page9.htm

Thanks

Connecting two resistors simultaneously won't give you the effect you want, it will in essence parallel the selected resistor hence you'd end up with whatever frequency is given by (R1+R2)/(R1*R2).
You need to sort of add the waveforms together, it can be done using op amps etc.

Thank you!

Hi Bittern. There is the 74c14 ic that might be best for your purposes. It's easy to use and wire and the internet is full of schematics. To get a good chord you may want to mix each oscillator, a tl074 would be a good bet.

Thanks oram I will look into this.