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...On the UBass: I still can't get used to the low frequencies coming out of such a small instrument. It's just weird to see it and hear it at the same time.
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I know. The polyurethane strings vibrate at about half the speed of steel strings of the same length. Polyurethane strings do not have the mass or energy of steel, but with the right pickup, that does not matter. The full story on purchasing that bass is complicated (very much a Goldilocks story), the order is this:
My wife began playing a short scale (30") electric bass, but did not like the look or tone
So I purchased a short scale acoustic electric bass and she did not like the weight, size of the body or the tone
So I had her play my fretless Steinberger bass, but she found it frustrating finding the notes (in tune)
So I purchased a Ashbory bass (also fretless), she liked the tone okay, but found the fretless part to be troubling and the reach between the notes seemed large to her
She decided that she wanted to try an upright, so I built her a upright suitcase bass, but she found it to be too hard on her hands
So I bought her the Kala bass and she found that to be just right.
That is the short version
of that story, it really was much more complicated.