Not wanting to hijack the very similar thread regarding the purpose-made sound chips on the market, I was wondering if any of the ghostheads out there utilizing the Arduino wave shield for their sound setup have had similar problems with that low bassy distortion at high volume levels when using the Canakit 7W amp or similar.
Unlike the tailor-made sound chips, the wave shield already has low pass filters and digital-to-analog converters on its outputs so I don’t believe that would be the issue, but I’m finding I can’t crank up the volume much from 1/4 to 1/2 full before the low-end frequencies start to break up. I’m using a single 4ohm 40W speaker so I don’t think that is the problem. But it is a relatively cheap speaker (Wal-Mart special) so maybe?
I know DIY sound users are few among us, but have any of you that do use a similar set up had a similar issue?
I apologize in advance if I should have posted this in the other audio thread.
Have you tried some other sound source driving the amp/speaker combo? If you hook up some line-level output from a source you know sounds good (like a home stereo component) do you get the same distortion? This could at least narrow down if the issue is probably in the amp/speaker or the output from the shield. I have not used a sheild, so do not have experience with that.
Mine has no distortion, Hamish. The reason is possibly twofold:
-
Dual, isolated power supplies - one 12V source for the arduino and lights, another for the amp.
-
The amp is a good distance from the rest of the electronics, a single non-shielded mono speaker cable runs to the waveshield.
Something else weird that I’ve noticed is that my amp seems to draw current through the audio leads… it’s powered on even when not connected to the battery. I’m starting to wonder if there’s an issue with my audio shield or the amp itself…
What magnitude is the current draw?
Other than where the inputs of the circuit are optically isolated I guess one should expect some small current flow.