Variation on dead string conundrum: less volume/sustain on open A

[Testing_123]

Hi all -- long-time TB lurker, first time poster here.

I'm playing a '98 MIM Jazz Bass. Bought it new and it has served me well through a variety of projects over the years.

The only annoyance I've had with it is minor, but has been consistent. Did a search here on TB, but this seems a bit different than what others have discussed, so here goes:

When playing amplified, the open A note sounds a bit duller than fretted notes up the fretboard on the same string or on other open strings.
To my ears, all sounds fine if playing the bass acoustically -- there's no apparent differences in sustain or note volume.

The problem has occurred with both roundwound and flats (which I'm using currently) and with different amps.

Instrument setup is good, not fretting out, no visible issues with the nut/nut slot. String action might be a little higher than some might prefer, but it works for me. I've added a second string tree to the headstock to increase the A-string's break angle off the nut, which seemed to help somewhat but did not fully remedy the problem.

I was starting to think there is some strange resonance in my band's rehearsal space that "masks" that note's frequency, but the problem doesn't occur when playing an A on the bass's E-string (same frequency).

In most cases I can bypass the problem by covering that A note on 5th fret E-string -- functional, but not always ideal. I know a decent compressor would help balance things, but I'm someone who prefers to fix things at the source when possible.

Perhaps I'm missing something. Any other troubleshooting paths I should consider?

Thanks in advance,

Jay

[testing1two]

I would start with a closer examination of the nut and the string path between the nut and the tuning post. Post some pics when you can.

[Testing_123]

Re-heating this thread to report on my solution -- prompted by another TBer's posting in a different thread on vintage vs. high mass bridges.

I had never noticed this on my bass, but the ground wire underneath my bass's bridge had caused the bridge plate to sit slightly off the body towards the G-side. Not visible, but I found I was able to slide a thin piece of paper under the corner of the bridge plate on the G side, but not the E side. Result: E string boomed, while other strings' vibrations (A string especially, apparently) were not being "transmitted" to the bass body to the same degree.

I pulled off the bridge, repositioned the ground wire, reinstalled the bridge, and voila! More evenly-matched volume across all strings, and the bass "feels" more resonant and lively on notes across the fretboard.

Duh. Wish I had found this awhile ago.

Cheers.