Sample lenght specifications for MOD,S3M,XM,IT,MPTM.

[FreezeFlame(Alchemy)]

Each format has as far i know its own type of supported sample lenght. With sample lenght, im writing about seconds of sample playback till it fully stops playing it and how big the sample can be (b,kb,mb,...).

For MOD, i know it can go up to 6 seconds in my experience and there's supposed to be an limitation of 64kb for each sample.
About the rest (S3M,XM,IT,MPTM), i have no idea .

[Saga Musix]

The sample length limit is always in bytes, not seconds. For MOD it's 128KB (not 64), for S3M, it's 256MB, for XM, IT and MPTM it's 4GB bytes (though in the latter case, all samples combined may not exceed ~4GB or else they cannot be addressed anymore). To get the length in samples, divide by the size of a sampling point (1 byte for 8-bit mono, 2 bytes for 16-bit mono or 8-bit or 4 bytes for 16-bit stereo). The length in seconds obviously depends on the sampling frequency. OpenMPT limits the maximum sample length to 2^24 sampling points (256 mega sampling points).