I have the same problem with 16th notes. Drives me nuts.
I've been working on an exercise from an old issue of Bass Player (May 2000 - pg. 24 - "Tom Kennedy On Adding Control To Your Technique"). Ex. 3 shows 2 measures of 16th notes and 16th note rests:
R = rest
C and A = notes to play
1st measure: CRCR CRCR ARAR ARAR
2nd measure: RARA RARA RCRC RCRC
I started as low as my metronome could go (40 bpm) and focused on the steps that were listed:
Step 1 -
The attack. (this applied to ex 1 which was 2 measures of quarter notes and basically talked about getting the click of the metronome to disappear underneath. Play with the metronome, don't follow it, as he stated.)
Step 2 -
Breaking down subdivisions. Here's where the 16th notes were brought into play. He stated: "mentally break down the...16th notes into individual increments and internalize them."
Step 3 -
Note durations. This talked about holding a note until you get to the next one. Release the note "just before you reach the next note or rest."
Step 4 -
Dynamics. This focuses on incorporating dynamics into the exercise, like increasing the volume slightly with each note.
I work on this exercise a little every day. I'm stuck at 65 bpm right now (don't laugh!

) with the 16th notes LOL. I get all messed up on the second measure.
Here's another exercise from an old Bass Player:
http://archive.bassplayer.com/z2000/...riedland.shtml
Hope this helps.
