Loud popping sound - NOT hitting the pickup

[jrbass70]

Bass - Lakland Skyline DJ4.
Behavior - When I slap on the E string (on the string, not at the bottom of the neck) I get a very loud popping sound. It does not happen on other strings. It happens fretted or open. I tested with both pickups and noticed the issue only happens when the neck pickup is on. I thought I was probably hitting the pickup pole pieces but I looked very closely and did not see any contact. I tried lowering the neck pickup anyway - I set it very low to be absolutely sure the string was not hitting the pickup. The sound was certainly not as loud (all sound was reduced due to the pickup height), but you could still definitely hear it. I also tried on multiple amplifiers

It almost seems as if the E string is picking up and accentuating more than it should and creating the bad popping sound. Of course whacking the E string not down by the neck creates more noise but this is distinctively loud and just sounds wrong. I also have a Fender P Bass, and Sterling Ray34 which have similar setups and don't have the issue.

Could it just be that the neck pickup is 'hot' or is there potentially something wrong with the pole pieces by the E string?

 

[Reedt2000]

Is it clipping your amplifier? So the pop is not a physical interaction but the preamp being overdriven in a sudden and unpleasant way? Is this bass hotter in output than the others you have? Its not an active preamp right? So it's not like you've got boosts cranked. Any pedals in the mix?

 

[jrbass70]

Is it clipping your amplifier? So the pop is not a physical interaction but the preamp being overdriven in a sudden and unpleasant way? Is this bass hotter in output than the others you have? Its not an active preamp right? So it's not like you've got boosts cranked. Any pedals in the mix?

No - it happens even when the amp is at a low setting, definitely not overdriving the amp. I did try with a few different amps just to be sure. This is a passive style J bass - I guess it could just be that the pickups are hotter, but I don't notice it being a lot louder than other basses when I plug them all into the same amp at the same gain/volume levels. I will say it is worse with the tone control all the way up. If I lower the tone control to be about 10-15% it's not too noticeable. And yes - I am plugged directly into amp, bypassing all pedals.

 

[Reedt2000]

Well, you've Isolated the issue to high frequencies. What is the amp EQ like? Do you run the same strings on all the basses? Which strings? Could it be a loose component in the cavity? Something like a loose pot that when you slap it contacts the side of the cavity or some other shielding? Does the jack crackle at all?

 

[jrbass70]

E

Well, you've Isolated the issue to high frequencies. What is the amp EQ like? Do you run the same strings on all the basses? Which strings? Could it be a loose component in the cavity? Something like a loose pot that when you slap it contacts the side of the cavity or some other shielding? Does the jack crackle at all?

EQ is flat - all my basses use GHS Boomers Med-Light (.45,.60,.80,.100). I doubt it is something in the cavity because I just had the bass completely shielded and grounded and all the electronics checked. I'm going to bring it back to the tech (the issue was happening before the job too), but I figured I'd ask here to see if anyone has run into or seen something similar.

 

[MidlifeBeginner]

I would try tapping the bass body in various spots. Also tap the pickup.

Another test would be using a pick on the E string. Picking hard can get you up in the output range of slapping, and easier to adjust. Picking can also give you a different view of what the string might be striking. Look at the bridge when picking hard.

Narrowing the problem down to the least effort needed to reproduce helps a lot in finding root cause.

Your description of tests done makes a pickup issue sound most probable. However, I am not sure what pickup issue could do that.

 

[jrbass70]

So I followed your suggestion and here is what I found -- Using a pick doesn't really reproduce the issue all that much. However, if I have the tone pot all the way up I really don't have to hit the string that hard with my thumb. Basically just letting my thumb almost fall on the string and I get the pop. Anywhere along the body and it happens. What I can tell you it gets even worse if I only use the neck pickup and it gets much worse the higher the tone pot goes. With the tone put all the way up - I barely have to hit it to get the pop sound. The lower I put the tone put, then I have to hit a bit harder, until at about 5-10% tone control it doesn't happen anymore.

Not sure how to interpret this but that's what I am seeing

 

[MidlifeBeginner]

Is that with your other hand in contact with strings to ground your body?

If you have a multimeter, check the resistance of the E string to jack ground and compare it to the other strings.

 

[jrbass70]

Yes - don't have a multimeter

 

[MidlifeBeginner]

Whatever is causing it, the pop is a sharp signal peak. Capacitors smooth out fast changes. Keep tone up all the way while tracking down the problem.

If there is a grounding issue with that string, I expect either pickup soloed would play to pop.

 

[jrbass70]

It's definitely a sharp signal peak - when my compressor is on it really helps and you can see the decibel meter shoot up to compress that pop sound. Only happens with the neck pickup. If I turn neck pickup off it doesn't happen. If I have both on you hear it, and even more so if I turn the bridge pickup off

 

[tchristian]

I would be tempted to swap the pickups, and their connections, front to back. Would reveal whether the problem is with the pickup or with the location of the pickup.

 

[Reedt2000]

E


EQ is flat - all my basses use GHS Boomers Med-Light (.45,.60,.80,.100). I doubt it is something in the cavity because I just had the bass completely shielded and grounded and all the electronics checked. I'm going to bring it back to the tech (the issue was happening before the job too), but I figured I'd ask here to see if anyone has run into or seen something similar.

You just had it completely shielded? I wonder if tapping it pushes something hot into the shielding. I'd open the cavity and pull the pickups to take a look.

 

[MidlifeBeginner]

Something beyond my understanding is probably going on with that neck pickup. Positioning makes some signals stronger on the neck than on the bridge pickup, but not a complete EQ cut.

If a loose connection in the pickup, tapping the body should do it. Only by touching the string sounds like magnetic induction voodoo magic. I stopped taking electronics before reaching that point.

 

[DJ Bebop]

Tweeter?

 

[jrbass70]

I emailed with Lakland and since my bass is under warranty, they are sending me another pickup. I’m going to take it back to tech who did shielding job - with the new pickup he should be able to figure out root cause. I will let you all know results.

 

[ardgedee]

Does the pickup have exposed pole pieces? If so try putting a piece of electrical tape over them and see if that affects the popping.

 

[FullumMusic]

I wonder if it’s a bad capacitor? Capacitors do go belly up from time to time. Or manufacturing imperfections lead them to not maintain their capacitance.

 

[landrybass]

I emailed with Lakland and since my bass is under warranty, they are sending me another pickup. I’m going to take it back to tech who did shielding job - with the new pickup he should be able to figure out root cause. I will let you all know results.

Very possible the cause, I’ve had brand new EMG P pickups bad from factory. The internal shielding was effed and picked up tons of radio signals and had a really weak output. And it was just half a P split set, just the E/A side

 

[juancaminos]

Is it the string striking frets. I had this issue once, I kept lowering the p-ups to no avail. Turned out to be the string striking the frets.