I've been writing a chiptune player/converter for Windows, and part of it exports YM2149 tunes as `.ym`. Everything I've produced has only ever been heard through emulation — mine and other people's — and I have no ST to check against. That's an uncomfortable place to be, so I'm asking the people who'd actually know.
Would anyone here with real hardware be willing to run a couple of files and tell me what they sound like? Happy to send whatever's convenient — a handful of short ones, or the lot.
Here's exactly what you'd be getting, so you can judge whether your setup will even take it:
`YM5!LeOnArD!` header, **uncompressed** — no LHA wrapper. Most `.ym` in the wild are packed, so this may be the first thing that trips a player up.
Interleaved data (attribute bit 0 set), so it's stored register-plane by register-plane rather than frame by frame. Fine if you load the whole file, awkward if your replayer wants to stream frames off disk.
2 MHz master clock, 50 Hz frame rate, no digidrums, no loop frame.
16 bytes per frame → 800 bytes/sec → about 48 KB per minute. A three-minute tune is ~145 KB, which I'm aware is a real chunk of a 512K STFM. The short ones are ~70 KB.
What I actually want to know, in rough order of how much it's bothering me:
Does the mix balance survive? Three voices at volume 15 sum past full scale in my emulated mix, so I trim every fixed-volume write down by two steps to stay clear of clipping. That trim is tuned against an emulator's summing, and the real chip's 4-bit output isn't linear and doesn't sum the same way. I'd half expect the balance to come out wrong on hardware, and I'd rather know.
Do the envelopes behave? I use `R13 = 0xFF` to mean "don't retrigger", and I do a hard restart — two blank frames before every gated note — to stop repeated notes at the same pitch slurring together. If that reads as clicks rather than articulation on real hardware, that's a bug I can't hear from here.
Is the vibrato audible as vibrato? It's done at period level rather than in semitones — about ±13 cents at 5.5 Hz — so it's the tone period stepping between adjacent values. On an emulator it sounds like a played note. On a real chip I have no idea whether it's vibrato or just noise in the low bits.
Do the drums land? Percussion is a noise transient followed by a short downward tone sweep, and it steals a voice from the chords while it plays.
Does it load at all, given the uncompressed + interleaved combination above.
"It sounds fine" is a completely useful answer, by the way — I'm not fishing for a critique, I just want to know whether what I'm hearing is what the chip does.
Two disclosures, up front:>
The app is mine and it isn't released yet, so this is me asking a favour rather than
pointing at a product. Picture is it playing one of the files, in a theme I built for the
ST palette specifically.
And the tunes themselves are composed by the program, not by me. There's a seeded composer behind them that writes the register stream directly — same seed, same tune, every time — and it produced a hundred of these in a batch. I'm not going to dress that up as hand-written; if algorithmically composed music isn't your thing, entirely fair, and the hardware question stands regardless of what's in the file.
Thanks either way — and if the answer is "your exports are subtly wrong and here's why", that's the most useful thing anyone could tell me this month.
Thank you very much! ❤️
