Selling Jazz bass pickups Tonerider Jazz Plus

[FaustoB]

I know it was a very practical thing to do, but changing the scale length and then after a while, changing the pickups would have been a more instructive way of hearing the differences in the pickups.

Moving the bridge will have changed the part of the string each pickup sensed, so either added more treble or more bass depending whether the saddle shifted forwards or backwards (I'm assuming it was a significant scale length change rather than just a couple of mm). That itself would have notably changed the tonality.

But obviously you've now got hum-cancelling pickups which can be a big plus. I fitted some Bartolini J-style hum-cancelling pickups to a Yamaha BB604 bass of mine that had very noisy single coils and it made a huge difference to its usability (and it did sound nice).

Good point Simon.
The scale length was about a 5mm-6mm change (5-6mm shorter). It's a mod that I shared & documented in some of my build diaries. This mod allows a fretless JB or PB bass to have an extra "fret" (21 frets, 3 full octaves from lower E to high E on the G string), instead of the standard 20 "frets" (from E to Eb, very weird to me).

When you play a fretless JB or PB with a full 34" scale, you can feel that that high E on the G string is almost there on the fretboard, just a mm or two out.. shortening the scale slightly makes the instrument a bit more fun to play, and having 3 full octaves feels like "closing a circle", without any noticeable change in playability. imo.

About the sound, it's probably hard to say, as my upgrade approach wasn't very scientific as you correctly noted, but based on what I hear, the sound profile changed a lot, way beyond what 5-6mm could cause, but I might be wrong.