Question about Ad-Lib era audio

[marurun]

Do we have any old DOS audio experts in here? I'm curious about something I feel like I see a lot of in Ad-Lib era audio on DOS: inconsistent tempo. A lot of music feels like it struggles to hold a steady beat, like any moment now the entire tune might just collapse into a disorganized jumble (Lucasfilm Games soundtracks definitely illustrate this). I'm sure this is NOT a case of the audio composers being idiots. I wonder what this stems from. Do the OPL2 and OPL3 lack internal timers and rely on PC timers that are subject to CPU interruption or something? If there are any resident experts, I'd love to hear your thoughts.

[MrPopo]

Have you ever tried comparing it with soundtracks running on Soundblaster?

[marurun]

Have you ever tried comparing it with soundtracks running on Soundblaster?

No. And I'm not speaking SPECIFICALLY about the Ad-Lib, I don't think. I haven't done a comprehensive survey.

[Anapan]

I noticed that in some games back then as well. I think the reason is the OPL2 chip is fed timbres directly. Any slowdown or lag in the game would result in delayed rendering of notes. Just a guess on my part, but I know it doesn't have any song memory or the like. I remember some games even asked in setup whether the user favored timing based on the graphics or audio rendering. Sound Blasters came with Adlib capabilities (usually an OPL2 chip onboard) along with digital audio playback.

[marurun]

That’s not too different from the NES or PC Engine.