Skip to content
Notifications
Clear all

Acoustic pickup buzz in some locations and not others


(@to_the_sun)
New Member
Joined: 12 years ago
Posts: 4
Topic starter  

I have a rosewood Gibson acoustic and a cheap single coil Fishman pickup for it. The pickup always buzzed heavily, but i was told single coils will do that so i bought a nicer one, an $80 Lace. Same exact buzz. I brought my amp, cords and guitar into the store where i purchased the pickup and we were unable to reproduce the buzz. Even on my old pickup the amp would not buzz. I then went to my parents' house and tried both pickups; the old one didn't buzz, while the new one did buzz, but would stop buzzing if you touched the metal input part of it. I have tried multiple outlets, cords and amps in each location (except the store). The results are always the same. At my house, both buzz. At my parents' only the expensive one buzzes. And at the store neither one did. This has to be some sort of grounding issue or something, but i don't know anything about grounding. Any help?

The old pickup - http://www.fishman.com/products/details.asp?id=27
The new pickup - http://lacemusic.com/acoustic_pickups/california_acoustic/california_specs.php


Quote
(@gnease)
Illustrious Member
Joined: 18 years ago
Posts: 5058
 

both of these are single coil pups, so each will have vulnerabilities. the main differences in susceptibility are going to be due to
1. shielding: this will help resist electric field (components) of noise, such as that due to spark noise from switches and dc motor brushes, as well as plasma discharge from florescent lights and (now old fashioned) CRT monitors/TVs, also e-field radiation from switching power supplies found in wall worts, and most electronics including laptops, cellphones, iPodish things … everything. also AM radio stations, and GSM/GPRS cellphones (we all know the GSM tattoo by now).
2. coil design: pup coils will pick up the hum from AC mains (house wiring, AC motors, florescent light ballast transformers and guitar amp power transformers <mostly tube amps>). if the design is large inductance coil and small magnet, it is more prone to picking up hum than smaller inductance (fewer windings, same direction) coils that use amps (active versions) or more powerful magnets. "design-wise", best ways to avoid magnetic interference pickup are humbucking or hum canceling dummy coil pup configurations. the latter basically is similar to the former except the dummy pup does not provide live signal output, only a hum canceling signal.

so when you write "buzz", what type of interference do you mean?

-=tension & release=-


ReplyQuote
(@to_the_sun)
New Member
Joined: 12 years ago
Posts: 4
Topic starter  

i suppose i should also mention that the pickups both also buzz when i am recording with them plugged into my interface. the buzzing with the old one was pretty bad; the new one was better, but it was still there. I used the bulit-in mics on my interface to record the buzz when you plug the acoustic pickup into the amp. you can listen to it here:
http://www.last.fm/music/To+The+Sun/............/buzzes+through+the+amp ...
first the amp is off, then i turn the amp on, then i plug in the acoustic. Sometimes, depending on where the amp is placed apparently, the buzzing will get louder or sometimes softer if you move the guitar close to it

also, i recorded the buzz it makes through the interface when recording:
http://www.last.fm/music/To+The+Sun/............/...as+well+as+when+recording+through+an+interface
this recording might be a little quiet, but if you turn it up you should be able to hear it. the first chord is strummed and recorded using the built-in mics on the interface, the second is the old pickup, plugged directly into the interface, and the third is the new pickup plugged into the interface


ReplyQuote
(@blue-jay)
Noble Member
Joined: 13 years ago
Posts: 1638
 

I couldn't get the first link at all, and the second link sounded not too bad. I didn't hear alot of buzz. I appreciate the fact that you were so specific, and precise in describing your set up.

It does seem like a grounding issue, with all of the foregoing details. I have no solution, but wondered if your house was near high tension lines, outdoor overhead wires, external AC feed wires, a transformer, or in an electromagnetic field, from within or without.

Then other houses could have underground cables , or a more solid ground. The guitar store would have plenty of sources of interference, but your issue was okay while there. So, maybe they have a certain industrial application to their wiring, I don't know.

I know that when you move your amp around it gets better or worse. I have that too, with a built in phase switch on my Tacoma that takes care of it.

Anyhow, the biggest clue is your touch. When you touch metal, your buzz goes away, so I agree in the first place that is is most likely grounding.

Bring some other guitars into the house, some electrics if you can get your hands on them, and try plugging them in. Get a guitar with humbuckers as well, to try. And a Tele on its middle position, or a Strat at 2 & 4 to do some serious trouble shooting and see wassup?

Actually, if you really wanted to get into trouble shooting, you migh fabricate cables or wire with alligator clips, and ground the pickup to a pipe or radiator, sink tap, IDK what you've got? I mean for a test - you aren't going to be able to play that way. I do things like that - got lots of jumpers and alligator-clip thingys.

Seriously, it doesn't get much more serious ; testing a pot here and/or an amp for good ground characteristics.

In the end, I think it will point to a problem in the house, and some houses are just like that.

Like a bird on the wire,
like a drunk in a midnight choir
I have tried in my way to be free.


ReplyQuote
(@gnease)
Illustrious Member
Joined: 18 years ago
Posts: 5058
 

I think I hear two different types of interference. the first (second strum) sounds like switching noise -- probably an insufficient shield issue for that pup. the second (third strum) sounds like it is a harmonic of 60 Hz. that is either caused by a ground loop (unlikely given the configuration), crappy pup cable or due to being a single coil pup. if the latter (as seemingly confirm by the changing position WRT you amp => changes interference), you are probably stuck with it. overall, the hum is not that bad. granted, you don't want to hear it on your recordings, but it's either change the pup (to humbucking or similar) or fix it in the mix (attenuate guitar during silent periods).

-=tension & release=-


ReplyQuote
(@to_the_sun)
New Member
Joined: 12 years ago
Posts: 4
Topic starter  

i went back to the store and made sure i got a humbucker pickup this time. the buzz is severely reduced, but not gone. unfortunately they had only one brand of humbucker, Dean Markley, and it's apparently not a very good one, because, when you put the pickup in the soundhole correctly, so it's low down and tight fitting, it picks up almost nothing at all. Next to no amplification. If you pull the pickup out some, so it's sticking out of the soundhole, almost touching the strings where it gets in the way of your playing, it picks up just fine. That being said, i haven't tested this one out much (while recording or in different locations), i just need to get a better brand of humbucker. Sooooo...

What suggestions do you have for the absolute best humbucker pickup that i would be able to go out and find?


ReplyQuote
(@greybeard)
Illustrious Member
Joined: 19 years ago
Posts: 5899
 

blue jay,

click on the second link. You'll see a picture of a cd jewel case - click on that and it will take you to another page, where there is a "track list". Listen to the first one - there are two things to be sorted out.

Firstly, you hear that the amp has a basic hum. Possibly caused by the house earthing.
As soon as the cable is connected to the guitar, the real noise kicks in. It is so loud that I'd put it down to something wrong in the circuit. Could it be that the cable is connected wrongly (e.g. sheath to centre)? One thing that I've suffered a couple of times is the strand short circuit. When you desheath the wire, you should always twist the core strands together, carefully. Sometimes, you miss one of the strands and it hangs off the side of the connection and as you move the cable around, it eventually hangs on the other connector, creating a short circuit. The result is that kind of noise.

I started with nothing - and I've still got most of it left.
Did you know that the word "gullible" is not in any dictionary?
Greybeard's Pages
My Articles & Reviews on GN


ReplyQuote