What's going on here, neck movement, truss rod?

[jazzyvee]

Here we go guys, I had a gig yesterday night at an out door carnival.  It was only a couple of days or so before the gig that I was asked to dep on bass. So having decided to take my burl maple series I bass i started working on the setlist, even up to yesterday morning I got a couple of successful runs through the set list before leaving for the gig.
I arrived about16:30 and our set was not until about 20:00 so spent the day watching the other bands with my bass on my back in my gig bag.


Sound check arrived and we went through a couple of numbers and all was fine in all registers on the bass.
Gig starts and I get to the part in the set where i'm moving down to the frets Low C up to E on the B string and F up to G# and the notes were choking out.


During the gig the choking started spreading up to about the 7th fret on both B and E strings and I had to jump around the fretboard to keep things working. In the end I turned up the bass and played really lightly to avoid the buzz and managed to get through the gig. No-one else in the band or my other half who was out from front mentioned anything wrong with my sound so I presume the sound guy did his job with a compressor to even things out.
I checked the bass when I got home and the the same areas were still choking out. I'm leaving it to settle in the case for a couple of days then will check it again.

But i don't recall any sudden changes in the neck like this before in the UK and I have played many outdoor gigs and festivals with this bass. However now I think about it, this happened once before when I was doing a cruise ship gig but that was kind of expected due to the massive climate swing between UK and the Caribbean and that time raising the nut slightly solved the issue.

If I had time between numbers my plan was raise the nut slightly but there wasn't time.

It wasn't an overtly hot or cold or rainy day either, just normal average summer weather for the area.

Any experience of this and quick fire remedy.
:-(

[edwardofhuncote]

Whatever the cause, relative humidity or temperature or some combination of them, the neck decided to lay back. If you'd had an Allen wrench to tweak the bridge up a turn or two, it might have gotten you through the set. I would not try to adjust the truss rods in mid-set... too time consuming. I'd be too rattled to play after that.


Has the bass returned to its former setup?

[JimmyJ]

An unwelcome surprise for sure but it can happen.  It's just wood...  And it sounds like you pulled it off without anybody else noticing so that was a success.  Sure made the set more interesting, right?

A quick 1/2-turn up of the low side of the bridge would have been the ticket.  The nut would not have made any difference (think about it). In that circumstance I'd also try leaning forward and pushing on the back of the neck while playing.  In other words, make sure you're not pulling it towards you while you play because that can have an effect on the action, especially if it's low to begin with.  Sometimes the difference between sitting and standing can affect the action, and the tuning.

You did the pro thing and played right through it so good on ya!

Jimmy J

[jazzyvee]

Thanks for the tips guys. Hopefully that does not happen again but If it does and I have time I will try to adjust the bridge. Out of curiousity, does the neck recipe have any impact on the sensitivity of movement due to to climate and/or humidity? For examples would a neck has  ebony laminates as opposed to purpleheart be more or less likely to move?

[hammer]

I don't know how hot it was in the UK yesterday and it may not have been that hot compared to the 90 degrees F that we are experiencing today in southern Minnesota.  However, what I do know, is that things can get pretty dang hot inside of a gig bag at this time of year given the position of the sun.  That's  especially the case if one's gig bag is a dark color and one is setting with their back to the sun. A couple hours of that, along with relatively high humidity, could have led to your problem.  My rule of thumb is that if it is too hot a day to have one of my dogs in the car, it's too hot for my bass inside of its gig bag or case to have any direct exposure to the sun.