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Discussion Starter #1
Hello from Montreal!

I see there are a lot of experienced and knowlegeable people on this site...isn't that cool!!

I'm hoping someone out there can offer up some suggestions on reducing the noise coming from my Seymour Duncan P90 pups. I recently bought a used Godin LG P90 and when I turn it up to a usable volume, the hum is unbearable. I've already lined all cavities with foil tape and grounded them. I'm also using an amp with built in noise reduction and this helps while I'm NOT playing.

Are there any options other than swapping them out? :eek:

Thanks!
 

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"Don't Panic!" - Zephod Beeblebrox

scottomy said:
Hello from Montreal!

I see there are a lot of experienced and knowlegeable people on this site...isn't that cool!!

I'm hoping someone out there can offer up some suggestions on reducing the noise coming from my Seymour Duncan P90 pups. I recently bought a used Godin LG P90 and when I turn it up to a usable volume, the hum is unbearable. I've already lined all cavities with foil tape and grounded them. I'm also using an amp with built in noise reduction and this helps while I'm NOT playing.

Are there any options other than swapping them out? :eek:

Thanks!
Google up the "gearnuts" site. This is a great site to help with guitar wiring. It has some super info on grounding and hum problems.

One of the main factors you will see is that most folks wire their pickups and controls totally wrong as far as grounding! Even some factory wiring is prone to these mistakes.

The biggest misconception is that ground is like the frame of your car - any metal anywhere is ok for ground. This works for light bulbs but is a guaranteed way to get hum in any audio circuit.

All grounds under the pickguard should be at one point only. That means the ground wire of the pickups and the ground return of the volume and tone controls. Usually you can bring them all to one terminal and then bring it back to the ground at the jack that feeds the guitar cord. This means hum currents can't flow all over the place and get in to the main signal. If the pickups have one shielded wire instead of two separate ones the shield braid is always the ground return.

Sometimes I see horrible messes of ground wires all over the place and big blobs of solder on the back of the pot/control metal cans. I guess the idea was to try to create a metal shield over everything. Usually it just makes the hum worse. If you wire the grounds properly you don't need to solder to the back of the controls at all.

Make your life easier and go to the gearnuts site!
 

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I've got an LG with p90's and it isn't bad wiring in this case. P90's are noisy, and if there are flourescent lights or if it is in an older house with older wiring (different codes back then) it just adds to it. Baseboard heaters etc can also add to it.

One friend of mine has an old Les Paul Pro with Gibson p90's and it is the same way. It is part of the nature of the beast.
 

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Also lighting dimmers on the same breaker as the plug that the amp is plugged onto, or computers and monitors on in the same room, can add significantly to the noise radiated into the pickups. I have to turn my computer monitor off, especially with my Axis SS with P90's, or the buzz is unbearable.

Brian
 

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So true Brian, computer monitors and laser printers are huge offenders are are game stations etc. That all being said though, I wouldn't trade my P90's a for all the tea in China.
 

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Discussion Starter #7
Hey Guys,

Thanks for the insight! I'll be heading off to gearnuts after this!!

WildBill - I don't know why the workmanship may be in question as I have done the exact same tricks on 2 other guitars I have, although they were not P90 equipped. (That and I've been in electronics for 20+ years so I'm familiar with proper soldering techniques) I actually don't do any soldering, I use the casing of the pots to make direct contact with the foil. Do you see any problems with that?

Brian and Ripper - I do have an old house (from 1958 and mostly ungrounded, and no baseboard heaters) and I do have a couple of flourescent lights in the house and a computer (which was off at the time). I guess I'll play by candlelight or something to check that out! I do love the sound from the LG.

I also played a 1978 Les Paul Pro just last week, through the same amp I use with the Godin and the sound was...too good to put into words. Let's just say, better than any other sound coming from MY gear! That's why I was so concerned with this guitar. P90's should sound great!!

Thanks again for your help!!
Scott
 

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P-90's sound great, but they can be pretty noisey. I am not sure how much you can do about that. I have owned several P-90 guitars, and all of them have had noise issues in some situations.

With most dual P-90 guitars, the middle position on the pickup selector is 'hum cancelling'.
 

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Discussion Starter #9
Hey Torn,

I expected some noise from these pups but I think this is excessive! The Les Paul Pro with P90's I played was noisy too but it was bearable.

From what I've read on the Seymour Duncan site the wiring of the neck pup is reversed as well as the magnetic field. They suggest loosening the screws on the back plate and reversing the magnets 180 degrees. This is how the 2 pups work like a humbucker. They say you can use a compass to verify this, but mine seem to show the magnetic field is north for both. I'm going to try this the next time I change the strings....unless I find another solution.

:food-smiley-004:
 

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torndownunit said:
I'm not sure how my Reverend is wired, but in the middle position it's completely silent.
Same thing with my PRS Soapbar SE.
 

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torndownunit said:
I'm not sure how my Reverend is wired, but in the middle position it's completely silent.
Most likely the neck pup is reverse polarity, so when both are on they function like a humbucker.
 

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Likely RWRP on the pickups, my Wolftone P90's are the same, although even in bridge or neck only position I find it no noisier than my strats or tele which for single coils is quite reasonable, easy to live with and great tone..
 

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PaulS said:
Likely RWRP on the pickups, my Wolftone P90's are the same, although even in bridge or neck only position I find it no noisier than my strats or tele which for single coils is quite reasonable, easy to live with and great tone..
I have the same experience with my Lollar P90s. Totally acceptable.
 

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Discussion Starter #17
it's funny but now I've played the guitar for a couple of months, the neck and middle positions are noisy but the bridge position is fairy quiet! Go figure!!
 

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Every single factor around the guitar affects the P90's too. You can plug into a bunch of different amps in the same room, and on some you will get noise and some you won't. They are just moody pickups. The tone is well worth it though :)
 

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torndownunit said:
Every single factor around the guitar affects the P90's too. You can plug into a bunch of different amps in the same room, and on some you will get noise and some you won't. They are just moody pickups. The tone is well worth it though :)
If I rub the back of my R4, I can hear the static coming through the P90s. I get a kick out of it.
 

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My MusicMan (P90's) Axis SS has the Silent Circuit, however you can defeat the circuit by taking the battery out. I have to say, as long as I don't have the computer monitor on, I don't hear a big difference in noise with and without the circuit. (Home conditions - I'm sure club/stage/venue conditions bring other complications.)

I was surprised by this, either I didn't make the comparison carefully enough, or the circuit doesn't "damage" the sound quality like I thought it might.

On this guitar, the middle position is humbucking, the other positions can have noise, but it's not in any way extreme.

Brian
 
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