I know I'm a late developer, but I've just accidentally discovered playing funk with flats on a J bass.
All 3 knobs turned up full, and straight in to my cheapass Behringer 802 USB mixer, using channel #1 for some boost from the mic' pre, and half a turn on the compressor.
Playing along to this through a high pass filter. It's so down and dirty, playing it in my Larry Graham (modified) style, I feels like a wild animal, and it sounds... it sounds exactly like the smell of sex.
Many thanks to the BCer who recently put me on to Betty Davis. I have the album now on Spotify. 👍