Amp or cab problem? Or both? I think I know the answer

[agedhorse]

I've been in the same situation many times Jimmy and it was always something that even after I found it, fixed it, and the sound went away, I would swear it couldn't have been that.

I see it all the time, over half of all reported rattle defects end up being something other than the cabinet itself.

 

[Cave Puppy]

One of the odd sources of rattles is air leaks in enclosures - an unused 1/4 inch jack, or a small leak where wood pieces don't completely seal - you get chuffing noise, which, since it's turning on and off at the rate of the air pressure changes, sounds like a speaker buzz. Until you've troubleshot one or two of those, they're really hard to figure out.

I had a Rumble combo that had a loose piece of the cardboard paper in one the port tubes. It produced a zipping kind of noise and was a bit different depending on note frequency. That took me about a month to find. Replaced the whole amp under warranty.

 

[Cave Puppy]

As far as the low end wonk your getting, I want to say it's just your bass bro. Those MFD humbuckers are freaking insane. I had a kiloton for about 3 weeks. I couldn't get a clean tone out of it. No matter what I did. People say play softer, and roll the volume back. I say, if that's the case then what I need to do is get another bass...so I did.

Truth. I have an MFD split coil (the one that comes on the SB-2) and that thing is untamable. They’re the only set of p pickups I have that are gathering dust (not installed in anything I have).

 

[lildrgn]

Haven't tested yet, kids still sleeping. But I do feel dorky having brought it up. I have worked in PC repair and support and have troubleshooting strategies for that stuff and for some reason, neglected to try any of those same ideas for my bass gear. (I think I was distracted by making a dumb video)

I did try the cabs separate yesterday, so I know that the buzzing seems to only be with the 210. I usually have it stood vertically; it is horizontal in the video because I thought that might stop the buzzing (nope). I think I also plugged directly into the amp (or at least with pedals disengaged) and the amp still made noise.

Lots to do, will report back later. Thanks everyone!

 

[trevcda]

I like your dog.

Read the whole thread and thought anything I might have added was already nicely covered. Had no plans to watch the video, as my computer's speakers are terrible, until I read that!

tl/dr- I came here for the dog!

 

[Lobster11]

I'll bet simply turning off the fluorescent light will eliminate the buzz that goes away when you touch the strings.

 

[micguy]

Truth. I have an MFD split coil (the one that comes on the SB-2) and that thing is untamable. They’re the only set of p pickups I have that are gathering dust (not installed in anything I have).

If you wire it in parallel, it’ll be manageable level wise, and you can load it capacitively (1500pF is a starting point) to get a wide array of sounds from it.

 

[Ric5]

to test for problems:

- turn off all pedals
- put a new battery in the active bass
- test one cab at a time
- tighten all screws in the cabs
- check all cables ... all of them ... swap them out an ab them
- try pedals one at a time
- unplug everything and leave it unplugged for a few minutes

 

[Cave Puppy]

If you wire it in parallel, it’ll be manageable level wise, and you can load it capacitively (1500pF is a starting point) to get a wide array of sounds from it.

Thanks and whaaaaat???

I tried several different wiring schemes with it. It has four conductors/wires but according to G&L themselves and to my own observations, coil splitting isn’t possible. How would I go about wiring one of those in parallel and loading it as you state?

 

[micguy]

Thanks and whaaaaat???

I tried several different wiring schemes with it. It has four conductors/wires but according to G&L themselves and to my own observations, coil splitting isn’t possible. How would I go about wiring one of those in parallel and loading it as you state?

Four conductor wiring means wiring it in parallel is pretty easy - It’s not coil splitting (using that term will cause confusion), it’s wiring the coils in parallel. I no longer have the bass with that pickup in it (I’m playing 5’s now), so I can’t give you color codes, but G&L can if you ask them the right question. Loading the pickup capacitively is simple for someone who knows a bit about electronics. If that’s not you, find a friend that does. You want to wire the loading capacitor from the top of the volume control to ground.

 

[Cave Puppy]

Four conductor wiring means wiring it in parallel is pretty easy - It’s not coil splitting (using that term will cause confusion), it’s wiring the coils in parallel. I no longer have the bass with that pickup in it (I’m playing 5’s now), so I can’t give you color codes, but G&L can if you ask them the right question. Loading the pickup capacitively is simple for someone who knows a bit about electronics. If that’s not you, find a friend that does. You want to wire the loading capacitor from the top of the volume control to ground.

Wiring diagrams for that pickup have two of the leads connected together, the other two being used as hot and ground. I suppose I could take the two leads that are connected together and connect them separately - in parallel, and add a capacitor as stated. I do know a fair amount about electronics but never heard of this doing this until now.

“You want to wire the loading capacitor from the top of the volume control to ground.” Isn’t the top (case) of the pot ground? To what exactly are you referring here?

Thank you!

 

[rickdog]

One of the odd sources of rattles is air leaks in enclosures - an unused 1/4 inch jack, or a small leak where wood pieces don't completely seal - you get chuffing noise, which, since it's turning on and off at the rate of the air pressure changes, sounds like a speaker buzz. Until you've troubleshot one or two of those, they're really hard to figure out.

I experienced that recently - an odd "rattle" from a PA cabinet. Sound tech put some gaff tape over the screw holes where casters had been removed - problem solved!

 

[micguy]

Wiring diagrams for that pickup have two of the leads connected together, the other two being used as hot and ground. I suppose I could take the two leads that are connected together and connect them separately - in parallel, and add a capacitor as stated. I do know a fair amount about electronics but never heard of this doing this until now.

“You want to wire the loading capacitor from the top of the volume control to ground.” Isn’t the top (case) of the pot ground? To what exactly are you referring here?

Thank you!

If you talk with an Electrical Engineer, the "top" of a pot (electrically) is where the signal comes in, assuming it's used as a potentiometer/voltage divider (which is how a guitar or bass with one volume control is wired).

 

[lildrgn]

Read the whole thread and thought anything I might have added was already nicely covered. Had no plans to watch the video, as my computer's speakers are terrible, until I read that!

tl/dr- I came here for the dog!

Great news, more dog content incoming. He's a great Bass Pupport Manager and oversaw my testing on the deck.

Prior to that, though, I tried with my P (lower output, minimal amp hiss, no cab buzz), my SB-2 (MFD pups, high output, definite amp hiss, light cab buzz), my Epiphone T-Bird (lower output, minimal amp hiss, no cab buzz). It was bass straight into amp, no pedals.

Even though I know G&L MFD pups have SUPER HIGH OUTPUT, 2 + 2 never added up; I didn't even think that those pups would be the source of my hissing/noisy amp.

I took my amp and 210 on the aforementioned deck, under 'pupervision, and tested. Though there was still stuff around, the rattling/buzzing was way down. Check out the new, <1min video and see what you think.

Bass Amp Troubleshooting, part 2 - YouTube

Long story short, I think this thread was much ado about nothing and really proves the KISS theory.

 

[tubatodd]

Great news, more dog content incoming. He's a great Bass Pupport Manager and oversaw my testing on the deck.

Prior to that, though, I tried with my P (lower output, minimal amp hiss, no cab buzz), my SB-2 (MFD pups, high output, definite amp hiss, light cab buzz), my Epiphone T-Bird (lower output, minimal amp hiss, no cab buzz). It was bass straight into amp, no pedals.

Even though I know G&L MFD pups have SUPER HIGH OUTPUT, 2 + 2 never added up; I didn't even think that those pups would be the source of my hissing/noisy amp.

I took my amp and 210 on the aforementioned deck, under 'pupervision, and tested. Though there was still stuff around, the rattling/buzzing was way down. Check out the new, <1min video and see what you think.

Bass Amp Troubleshooting, part 2 - YouTube

Long story short, I think this thread was much ado about nothing and really proves the KISS theory.

As has been mentioned a) the dog is awesome and b) it can be something other than what you think. Glad you seem to have solved the problem....without really doing anything.

Story time:
I thought I blew the speaker in my tiny Hartke kickback combo. It was farting at medium volumes and I had no idea why. It turned out the wire, that connects the amp to the speaker, was vibrating. I added some extra batting to the inside of the cabinet to isolate that cable. Problem solved.

 

[Cave Puppy]

If you talk with an Electrical Engineer, the "top" of a pot (electrically) is where the signal comes in, assuming it's used as a potentiometer/voltage divider (which is how a guitar or bass with one volume control is wired).

Thanks. I totally understand that concept.

 

[vmas]

I went through a similar situation when I switched amps from SWR Silverado to GK MB212. I found that lowering the volume on my ASAT to about 3/4 eliminated the rattle. As someone else mentioned, those pups are hot. I would have sworn a speaker had blown.
Do you not have a parallel/ series switch on your bass?

 

[micguy]

Thanks. I totally understand that concept.

Good - you're welcome.

 

[Nebadon2000]

Good - you're welcome.

Lower Pickups? Clean/check output jack on bass and internal wiring? Battery if active?

 

[Killing Floor]

+1 for firing the drummer.
But has anyone suggested a preamp pedal bender? Sometimes buying 5-6 pedals is the solution.