I'm planning to use STA540 in a guitar combo, because it's one of a few chip amps that can give me about 15W with 12V supply and 4ohm speaker.
My problem is that the chip has four amplifiers and I will be using only two of them (bridged). What should I do with the other two?
- Ground the inputs and leave the outputs hanging.
- Use the second pair in parallel with the first one. This probably won't help me push more power to the speaker because I think I will be limited by input voltage and not the IC itself and I don't see any other advantages of this
- Find a smaller IC -- but I already tried that and didn't succeed....
- Use them to drive headphones. Is this realistic, or would the headphones explode?