Connect headphones to arduino

Other Hardware Audio
1

So I've been looking at building a synth with an arduino. I read a lot of articles that were telling you can't connect headphones to the arduino because of the input impedance and the square shape of the signal.

I came across this article (link below), which basically calculates a wave and sends it out as a fast PWM signal. By connecting an RC-filter, they get an analog signal that varies between 0-5V.

Would it be possible to connect headphones to the output of the filter? Or will I still have problems?

Kind regards

2

The output of that filter is high impedance, if you connect your low impedance headphones to that the signal will collapse.

High impedance headphones are a thing of the past, you have to get them from vintage shops these days.

What is wrong with using an amplifier?

3

That transistor circuit driving an 8 ohm speaker is a very cheap/cheerful solution to the impedance issue I suppose. Puts DC bias on the speaker though which could be fatal to headphone drivers alas...

Amplifier chips are the way to go really, yes.