I have a place off grid with a 12 VDC system. I have been changing out all of my lights with 1 and 2 watt 12 volt LEDs. The problem I'm running into is the noise coming through the stereo speakers. I have some 1 pair shielded wire I may try, but I don't want to re-wire if I don't have to. Any suggestions?
The convertors that supply the LEDs are switchmode and are making lots of noise .You can use linear instead with a loss of efficiency .You could buy better more expensive convertor .You could start to filter the wiring first at the Led fitting .If things are still bad then shielded cable will help .
You may try to use suitable capacitor on the out of your VDC point. But I don't know your circuit, you need to find best uF value to use.
Don't forget to add cooler metal for your transistors. Also check them whether they are in true working area or not.
Also coil and capacitor resonance is a point for your circuit to get clear voice.
Don't forget to get equal ohm value from your circuit to out point to the laud speaker's ohm value. If yours is 8ohm, your circuit should out 8ohm total resistor value.