I know the Pink Floyd toms on "Time" are rototoms, which are tuned to specific notes.

https://en.wikipedia.org/wiki/Rototom

That would account for the melodic quality. And then there's a bunch of reverb.

You can make pitched toms easily by using 4mat's method above, or even just sampling/synthesizing a triangle or sine wave, and using a short envelope for pitch and volume. Add noise to taste.

Do it on the pulse channel with a long portamento fall off.  Galway & Hubbard were both good at this where it comes to the musical side of the toms.

Put a bit of noise at the start for a couple of frames to give it the percussion kick, also you can try cycling the duty waveform quite rapidly if you want it to sound more like the old Miami Vice '80s toms.  (the name entry track Galway did for Rambo does this very well.

If you were doing it on the c64 you could use the tri wave with noise which would give you more of an acoustic feel.  The long fall off on the portamento is key though to keep it musical.

Maybe not strictly a chiptune thing here, but figured folks here may have some ideas...I'm trying to replicate a sound that I've been hearing in music for years, but am just not quiet sure where to start. It's this sort of melodic tom tom sound with heavy reverb that kind of sounds almost like musical notes. I am not sure if maybe there's a specific way to get it, but I thought I'd reach out to the folks here.

https://youtu.be/mOFW8gLxB94?t=1m11s

https://youtu.be/u06DpcFXc4U?t=3m12s

https://youtu.be/rL3AgkwbYgo?t=1m50s

The simplest thing i thought of would be just to take a good tom sample, then load it in a sampler so that it would pitch up and down as i hit different keys on the keyboard. But it seems like there is more than the sound to this.

Tools I have that might come in handy:
EW Storm Drum 2
EW Quantum Spaces Reverb
BFD3
Logic pro 9

Just wondering if anyone's ever happened across a sample kit for something like this?