I want to play a simple 30Hz frequency tone trough a JBL Charge 4 via the jack connection cable.
To play the sound I used this Tutorial
I wired everything up according to this Tutorial and plugged in my headphones, which worked.
Now my question, would it also work with the JBL Box or other Boxes with a Jack connector? Or is there a problem with too high amps for the Arduino when the speaker gets bigger?
And does it make a difference if the speaker has its own batterie/ power connetion?
Amplified/powered speakers are fine. The load on the Arduino is "high impedance".
It's a good idea to put a capacitor in series between the Arduino & speaker input. The Arduino's output goes between zero and +5V (it has a "DC bias") and some amplifiers don't like that. Regular audio signals are AC. With the capacitor the signal goes between -2.5 and +2.5V. 1uF is about right (with the + end toward the Arduino).
You cannot directly drive a regular (unpowered) 4 or 8 Ohm speaker. The Arduino is rated for 40mA "absolute maximum" and from Ohm's Law that works out to 125 Ohms minimum. (You can put a resistor in series but the volume will be very low.)
Note that it takes a fairly-large woofer or subwoofer to reproduce 30Hz but since you have a square wave there are lots of harmonics that you'll hear. (The lowest note on a bass guitar is about 40Hz,)
I once had an extremely efficient set of speakers that I ran from the headphone jack of my tape deck, because I had no amp. I suggest trying with a 220 ohm limiting resistor. But most of today's speakers are horribly inefficient even though the magnets have improved so much over the years. That's because they are designed for higher power levels and small, inefficient cabinets.
Hi. Thank you very much for your answer.
If I use a powered speaker everything works fine with the capacitor. Would it also be possible to use a "unpowered" speaker over a mosfet with such a capacitor. I tried it myself, but I couldn't get it to work. I tried those two circuits, since I only had n-channel mosfets:
Do I need to use a p-channel mosfet or another resistor? Or is that just not possible at all?
Your problem is "seat of the pants" electronic design. The capacitor in series with the load circuit, prevents any speaker current from flowing, once the capacitor charges in a few milliseconds.
Also, a driver circuit with an impedance of 220 ohms, driving a 4 ohm load, is "dreaming in technicolor".
Do the smart thing - use an amplifier module. They're available and cheap.
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