Testing the TI Flats on a Fretless P-Bass (no talking)

This is a follow-up to the first video, showing a possible problem with the set of strings on an Ibanez TMB310. To see if it's a problem with the bass, I put them on this homemade fretless P-bass. They have the same problem here too. To me, that pretty much points to the strings themselves. Background: I'm pretty new to TI Flats, so I'm not sure how a new set should sound. I'm getting different responses though, from this set: a wide range of harmonic response and also loudness. I really like the sound of the D string - it has a very clear fundamental. But I'm not sure if that's the "TI flats" sound or not.