I'm not using anything but simple ANSI C and the standard library (plus some code from Serdaco for driving the OPL2LPT, hacked to support a regular Adlib as well). I should probably be using Allegro, but I'm too lazy for that :P
The last time I touched on Pascal was some good 10 years ago, maybe more. It's a fine language, but I grew too used to C(++) to simply give up from it. Sure, up until 2 years ago, the move from C++ to C would sound ludicrous to me, but now it made perfect sense.
To be honest, as much as I know about interrupts in theory and have invoked quite a few from ASM embedded em C, but not 100% sure I'm doing it correctly. It works and nothing blew up in flames (yet), so I'm ok with that, but I would love to play PCM sound over a Sound Blaster some day. Maybe I will have to get down to some protected mode ASM. But not today.
For running on modern platforms, in situations where there's no direct PCM sound, I simply play a recorded version of my OPL2 sound (like, for instance, what I did with the Android version of Noudar: https://play.google.com/store/apps/details?id=pt.b13h.noudar) - works surpringly well.
I also always keep a debug version working with SDL, so I can leverage modern development tools and simply have a DOS/Amiga/etc Makefile.
Keep the good stuff coming! :D