I used the Pulse-Width-Modulator of the PMs sound generator to play real wave samples. By changing the duty of the output wave it is possible to “emulate” an analog sound signal. The output sounds quite good, but the PM is not loud enough so it’s a good idea to hold your PM close while testing these ROMs.
I noticed that 8 bit samples sound more awfull then 6 bit samples, in this version you can use the B button to decrease the bit-width of the samples down to 5 bit (i think 6 bit sounds best) and the A button to increase it again (up to 8 bit of course). This problem probably occours because the lower the bit-width of each sample the higher the PWM units frequency (which in turn results in a better signal quality).
Here’s the link to the sample binaries and source.