Sounds like there just isn't enough output. Couldn't you just raise your pu's a little? Or perhaps even just turn up the gain on your amp a touch?
Or am I missing the point here?
No, you're actually spot on - this is in fact one of those lengthy and hair-pulling experiments you're likely to go through trying to get a clean tone out of your Rick without having to resort to either a pick or weight-training on your right hand to develop the strength you need.
I certainly did all of those things to no avail (including strength training on the right hand!).
Flatwounds and lots of compression helps a little bit and plucking directly over the bridge PU will help too. But nothing compares to a different bass with a better tone
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