Back in 2001 when A Funk Odyssey was released, a test pressing of the album surfaced, which contained some short "interludes" of Jay messing around with a vocoder (a sound effect that can make a human voice sound synthesized).  When Feels Just Like It Should came along a few years later, this sound was revived and used as the bassline to the single. In a new interview with Jay, he describes where the sound came from:

"On the end of the last album I was mucking about with a small machine called a Helicon, it’s like a voice synthesis thing, you twiddle it and it makes you sound like Barry White, or it gives you three part harmonies or whatever. I was mucking about with it I went off doing this beatbox thing which we recorded and kept. There was a little part of it that I thought would be great with a beat over it, but we never got around to doing it. So this time around we fished it out and cut out the piece that we wanted and Derrick played the beat over the top and already you could just see this thing forming and it was heavy. I sang it completely differently, I tried to sing it in my normal register and there wasn’t really anything happening, it wasn’t really going where I wanted it to, and then I tried it falsetto and it kind of gave it this Curtis Mayfield kind of funk, this Wild Magnolias kind of flavour. I just thought it was a good flavour, something different."

To hear the original sample from 2001, head over to the downloads page.