The one I have reads notes from a file and can play chords. The quality varies the radio used, location, where tuned, and various other things. I think it can be better than the sample I have but I need to play more.
Some archive of songs and source are at ftp://metalab.unc.edu/pub/academic/computer-science/history/pdp-8/music/
More at ftp://ftp.dbit.com/pub/pdp8/nickel/music/
I also have an RK05 image of a DEC diagnostic pack with a music program and music files at ftp://ftp.pdp8online.com/images/os8/ file diag-games-kermit.rk05.
Samples of Beethoven 5th. Starts with the beginning of the song then
I stopped the program and started the next song (the 5th third) loading.
The strange sounds are the EMI from the computer while reading and processing
a file from the RK05 drive. The .wav file is closest to the original sound
but the others sound better with some of the high frequency removed.
As a .wav file (530K) (Should work on windows systems)
As a .mp3 file (191K) You may need to right click to download and use a special MP3 player.
As a .au file (382K) (Sun, unix etc)
More to come later. More samples, hopefully better, more information. Possibly live playing from my machine. Email me suggestions below