EBMM SR5 crackles, but only when slapped!?!

[btp]

My EBMM SR5 H is lovely and sounds great, but has a bizarre problem. When I play fingerstyle, it sounds perfect, no matter how hard I dig in. But when I slap, even quite gently, it makes a crackly noise (almost like a bad cable).

In an effort to isolate the problem, I have swapped amps & cables; played direct into the sound board w/ headphones; etc. I play almost entirely fingerstyle so I only noticed this recently, and it would be impossible to detect playing live. The basic sound is great -- but the side of my thumb seems to add a certain je ne sais -crackle- to the mix.

I can easily reproduce the problem by simply playing the same notes with my fingertips (no crackle) or the side of my thumb (crackle). But I am totally stumped as to what might cause this, especially on an instrument with a reputation for (a) great slap tone and (b) great quality.

Thoughts?

 

[madbassplaya]

are your strings hitting the pole pieces when you slap?

 

[btp]

Not even close to the pole pieces. What kills me about this is that I can dig in seriously hard with the fingertips and sure, I get fret noise, but no crackle. When I just tap gently with the side of my thumb, like you might do on the steering wheel when you're bored, it crackles. And yes, my medication is adjusted. ;-)

 

[perogato02]

Maybe a detached wire?

 

[btp]

So it's time for exploratory surgery, I guess...

 

[BuffaloBass]

Most definitely. Likely a bad connection, or a "cold" solder joint which sometiems is hard to ID visually.

 

[FunkMetalBass]

Have you tried just slapping the bass body to see if it still makes the crackling noise?

 

[btp]

Thanks for suggestions. Very much my suspicion as well: "bad connection" or "loose ____". And yes, I have tried just thumping on the body to see if the vibrations cause the noise... if it happens at all, it's nowhere near as evident as it is from gently tapping the strings. And playing fingerstyle, Really Aggressively, causes a lot of vibration, but no crackle. And I've got my left hand firmly on the strings (to mute all but the one I'm playing) the whole time, either way, so I don't think it's a difference in grounding (unless my left hand is much less conductive and my right hand)...

Hopefully I will have time this evening to investigate a bit more. I should post clips -- video clips -- because if I was reading this thread, I'd be skeptical...

 

[FunkMetalBass]

I just can't fathom why the sound wouldn't be there except with one specific technique. I'm presuming it's not just clackity presence from EQing.

Clips would definitely be helpful, especially if you could also record the normal/aggressive fingerstyle to give a control.

 

[mikezimmerman]

I remember having something that sounds kind of like you're describing, and it turned out to be dirty/oxidized contacts in the jack. The plug was not making perfect connections, and something about the dynamics of slapping brought it out the fact that the signal was not always able to get through cleanly. Try contact cleaner on the jack, and see if that helps--it may be something different entirely, but it's worth a shot!

 

[btp]

Thanks Mike -- I will try cleaning the jack... In the meantime, here are clips. I've been calling it "crunching", but it sounds more like static here. So I will call it static.

http://www.msu.edu/~pentlan2/sr5-clips/fingerstyle-soft.mp3 Fingerstyle soft (no static)

http://www.msu.edu/~pentlan2/sr5-clips/slapping-gently.mp3 Slapping gently (static)

http://www.msu.edu/~pentlan2/sr5-clips/fingerstyle-hard-then-slap-gently.mp3 Aggressive fingerstyle, then slapping gently (static starts when slapping starts...)

These were recorded with a Tascam USB interface into Garageband, no effects, and a fairly new set of Fender 9050 flats, which are great. The only time the static sound shows up is when I play with the side of my thumb. I tried it with a pick: o static.

One interesting new piece of evidence: when I first set up to record, there was no static with any style. After about 2-3 minutes, it's 100% reproducible. Maybe my thumb is oxidized?

 

[btp]

And some results from exploratory surgery:
1) Bang as hard as I want on the back: no static.
2) Tap firmly on the pickguard near the switch: small amount of static.
3) With pickguard/pre-amp out, I can flick the preamp circuit and the pots: no static.
I'm thinking maybe the switch??

 

[Rano Bass]

2) Tap firmly on the pickguard near the switch: small amount of static.
3) With pickguard/pre-amp out, I can flick the preamp circuit and the pots: no static.
I'm thinking maybe the switch??

I think that is your answer, time to take the bass to a good tech or just check the switch yourself if you know how to do it.

 

[iunno]

Try rubbing the pickguard, my Ray 34 does this as well, although I'm not sure if it does with a grounded outlet.

 

[btp]

I'm leaning towards just taking it in. I could futz around endlessly and perhaps do more damage than good...

But the interesting thing here relates to the comment from FunkMetalBass:

just can't fathom why the sound wouldn't be there except with one specific technique.

This is exactly why I started this thread. If any of you-all held it in your hands and played it yourselves, you still would not believe it. We just have to respect the fact that the instrument vibrates in deep and mysterious ways!

 

[fitani]

Had the same problem with my HH. Crackle when I slapped or dug in fingerstyle. turns out it was the switch vibrating in and out of contact. I temporarily shoved a piece of business card under the arm/lever to keep it in place. Still have it there.

Anyone know where I can get a replacement switch online?

 

[btp]

Wow! So I'm not crazy? How about that...

 

[btp]

Cleaning the switch with a compressed air cleaner did the trick. The static is gone, no surgery required.