There are a ton of Youtube videos out there with amazing bassists using this technique. Want to learn how? As a disclaimer, this takes a lot of time to get to a functional level, I spent 4 months of consistent practice before I was able to use it. That being said, the technique is totally learnable with regular practice, this step-by-step guide will help. I was not a slap player at all until I got this technique under my belt. The message is: don’t give up! After doing it a thousand times the precision and speed will come, remember speed comes from accuracy!
First, you need to get used to slapping down and in on the string. You are striking down so that your thumb comes to rest on the string below your target and in towards the bass body. If you are looking down at your bass your thumb should rest so you see almost half on it on either side of the string (video 1). Get good at this. Just practice the down/in slap until you can do it consistently on all strings (remember, possibly weeks!), then move on to the other steps.
Once you are used to slapping down/in you need to practice the up/out maneuver. When you thumb is resting below the target string, hook it around behind the string above and pop it out (video 2). You want to practice this move in isolation at first, but then link it with the down/in slap (video 3). User your metronome: play so that your down-in-slap is on the click and up-out-pop in between.
Once you are doing it consistently at a slow speed (40-50 bpm) start working your way up and gradually increase the speed. The key here is to develop consistency in the timing of the technique, I can’t stress enough how much this matters. Repeat: speed comes from accuracy! Accuracy is built by doing it SLOWLY! (a lot!!!!)
Lastly is the finger snap. Hook your index finger around the string and snap it. The key here it to keep you index finger curled before hand. It takes too much time to bring your finger up to snap if it’s straight or hanging loose. The best way is to get used to having your finger rest on the string below your target before you snap it (video 4). Again, this can be practiced in isolation and then with the other techniques. Work with the metronome, do the previous drill counting triplets on each beat:
Put them all together and you’ve got it! I know, it sounds clunky at first, and there’s no short-cut. This is a technique that requires a lot of muscle memory which takes time (and tons of repetition) to build. After you have the basic motion on one string, start expanding to the other strings and play scales. Ascending the finger-snap helps you to cross strings, descending you reset your hand position on each string (video 5). Same as above, use a metronome to keep your timing consistent and gradually increase the speed. Expect this to take some time; it’s a difficult (but learnable!) technique.
The beauty of this technique is that it allows you to produce very fast sets of triplets (video 6). After you get comfortable with it you can start experimenting with different patterns. A pattern I like is using the down-up-snap over a chord alternating with my thumb between the root and the fifth to create a pad to for others to solo over (video 7).
This lesson created by Evan Kepner, a regular contributor to notreble.com.