This is from the book/CD "Standing In The Shadows Of Motown" - it is Bob Babbitt playing the James Jamerson bass part for "Ain't Nothing Like The Real Thing". This is a perfect example of an awesome, mid-rangey bass tone that sits well in the mix. I assume this is a Fender Precision. The thing I find most surprising is that you can hear some scrape sounds when Bob changes position - indicating that he is using roundwound strings! If you take this clip an send it to a mixer, then blend the bass-only track with the backing track, you'll see how well this tone sits in the mix. It may be true that to sound like Jamerson, you need to use flats - but - maybe rounds are a better choice for that style of music. Jamerson used what was available at the time - it seems like Bob is using a later technology to achieve a tone that is similar, but maybe even a little better?