Thanks for these comments guys. I have used these strings on the bass for four years, so my action and playing style is perfectly adjusted to them.
The bass is a through body, so I never twist the string around the tuning post when tuning up; just bend it into the tuner and then wind without any wrapping around the tuner by hand.
You can hear it through the amp. It doesn't sound quite the same as it does acoustically, but it certainly doesn't sound right.