However, one source describes how to generate left and right channel outputs 90 degrees phase shifted signals, using two leds in parallel, which will cover the 38kHz pulses by ways of both positive and negative "difference" pulses. Others talk about phase shifting one channel by 180 degrees to allow for higher voltage to drive the LEDs.
What is your take on a effective way of combining two lower frequency "audio" channels to cover higher frequency pulses?
Note that if you are using "stereo" and connect your LEDs between the left and the right channel (ignoring ground), the resulting signal L-R is simply a mono signal that you could have generated to start with. The only advantage is that you can get the double amplitude, which is only of concern if you turn up the volume to the max, and it is still not enough.
I think that everybody has leftover smartphones which have been made redundant by planned obsolecense. Fortunately, some of these devices have a chance to be made useful again.
Have you considered using something like
this device connected with USB?
