three fingers and a thumb?

[dlmarquez]

Anybody out there use the thumb and 3 fingers a la classical guitar?
I'm working on this technique with my fretless, and I love the sound I get playing about 2 inches in front of the bridge, it's got some of that "Jaco" tone, but it's punchy and penetrating unlike most fretless sounds.
However, I have difficulty getting the thumb downstrokes to sound like the finger upstrokes...the thumb tends to sound much fuller...any suggestions other than structuring my lines so that I only use the thumb when I want that full bottomy sound?

[fishsticks]

use a lighter touch with the thumb... and also use a heavier touch with the three fingers.... practice making the tones even across the fingers hard and soft for versatility's sake. and use just the edge of your thumb.