Pick up buzz due to hot pickups / dirty house power

chinjazz · #1 01-13-2012, 07:17 PM

Hey Folks,

Thought this might be a good place to post this.

I'm trying to address an issue on buzzing noise with my bass pick ups.

It wasn't an issue before, but with a drop in temp outside, and what I think isn't such a clean power source in my house, I get a very healthy buzzing on my bass. Lifting fingers off the strings (when I touch the bridge - all gone). Nordy Big Singles in this bass.

On a lower output bass I don't have this problem.

I got suspicious of my power source and tried these 2 tests:

1) Plug into an iPad with Apogee Jam - no issues
2) Plug into MacBook Pro (battery power) - Firebox powered from laptop - no issues

It seems like my house power is not clean. Anyone know what I can do to nip this issue?

Thanks and happy Friday!

~ A

chinjazz · #2 01-15-2012, 05:57 AM

Oddly enough, yesterday the issue went away. I'm thinking someone in a nearby home has some power tool or something introducing this into the common power lines we all share. I don't know. This is a mystery.

SGD Lutherie · #3 01-15-2012, 08:12 AM

That's not really an issue with the bass per se, but shielding will help in those situations.

Avalon · #4 01-15-2012, 08:44 AM

Hi Chinjazz. I'm curious about this issue as well. Have you tried to add any shielding to your bass?

My understanding is that there are two types of interference, one being RFI and the other being EMI. Apparently you can use either aluminum foil or copper foil for shielding the interior compartments of your instrument. However, copper is often preferred. With aluminum, it is nearly impossible to get a good solder. I've seen that soldering of the foil sheets is strongly recommended, and therefore the copper seems the easiest choice. Still, some people still have shielded with aluminum foil held by glue and electrical tape or screws. Aluminum advocates claim to achieve excellent results at a substantially lower price than copper.

The reason I make the aluminum-copper distinction is that copper is better at conducting emi while aluminum is better for rfi or vise versa (which is better for which?). Both materials can abate both types of interference, but each performs slightly better than the other in difference ranges of interference.

I don't know what kind of interference is the most common, but apparently both can be a problem. According to Wikipedia....

"Broadcast transmitters, two-way radio transmitters, paging transmitters, and cable TV are potential sources of RFI and EMI. Other possible sources of interference include a wide variety of devices, such as doorbell transformers, toaster ovens, electric blankets, ultrasonic pest control devices, electric bug zappers, heating pads, and touch controlled lamps."

Which one are you contending with? Who can tell with so many possible sources? Once I figured out that I had to turn off one of our outdoor floodlights to eliminate some buzz I was getting. On the next occassion where I had buzzing, turning off the outdoor lights didn't help.

However, as I understand it, for most environments either material (copper or aluminum) will work sufficiently to shield from both forms of interference. So is more of a good thing better? Would a layer of aluminum foil covered by a layer of copper foil (with conductive adhesive) work any better or would it create problems?

chinjazz · #5 01-15-2012, 09:48 AM

Quote:

Originally Posted by SGD Lutherie

That's not really an issue with the bass per se, but shielding will help in those situations.

True, as it actually completely went away today - with no changes on my part. Shielding the pick up cavities I'm told may affect the tone to some degree. To what Degree I'm not sure.

When I lived in a different home I had some crackling issues with a different bass (DJ5) whenever my finger would hit one of the exposed poles of the pickup, and if my fingers swiped the pick guard... I went to town on shielding, and basically that quieted it up a bit. There was something to the air being dryer and in the winter that caused it to be more prevalent than in the summer.

I'm sort of inclined to do nothing about it with this bass because it's a higher end instrument and I don't want to affect the tone, but "ya never know" what I'll end up doing.

Today... Is a good day, with no buzz...Really annoying when it happens truthfully, especially if I'm recording... When that happens I disconnect my AC power and go all battery powered on my laptop/firebox interface... Sort of causes me to nail it as much as possible with less time to play with (batt).

Thanks for the feedback Avalon & SDG Lutherie!

tabdog · #6 01-15-2012, 02:54 PM

A good power conditioner may help.
Most gigs are close to all kinds of
interference. It never hurts to have
a good power conditioner if you are
serious about playing bass.

Tabdog

chinjazz · #7 01-15-2012, 03:46 PM

Quote:

Originally Posted by tabdog

A good power conditioner may help.
Most gigs are close to all kinds of
interference. It never hurts to have
a good power conditioner if you are
serious about playing bass.

Tabdog

Hey Tabdog,

What sort of power conditioners do serious bass players get?

I have a few triplite power strips with 'isolation' on them, however no mention of conditioning.

Thanks,
A

DiabolusInMusic · #8 01-15-2012, 04:03 PM

Monster power conditions work quite good. Honestly go into a good electronics store they can offer many.

But you really should shield your bass. It's a must for me, I cannot stand when a bass "hisses". I've never heard of anything about it affecting tone, I do it to all my basses (when necessary).

As far as electrical noise, you want to keep your bass amp off the same circuit as any compressors or anything that kicks in and out with high amps, like a fridge.

SGD Lutherie · #9 01-15-2012, 04:30 PM

Quote:

Originally Posted by chinjazz

True, as it actually completely went away today - with no changes on my part. Shielding the pick up cavities I'm told may affect the tone to some degree. To what Degree I'm not sure.

No, it wont do that. I totally shield my pickups, and there's no difference in tone.

What will change the tone is if you wrap foil around the coil so that it forms a closed loop. That will remove some high end.

chinjazz · #10 01-15-2012, 04:31 PM

Quote:

Originally Posted by DiabolusInMusic

Monster power conditions work quite good. Honestly go into a good electronics store they can offer many.

But you really should shield your bass. It's a must for me, I cannot stand when a bass "hisses". I've never heard of anything about it affecting tone, I do it to all my basses (when necessary).

As far as electrical noise, you want to keep your bass amp off the same circuit as any compressors or anything that kicks in and out with high amps, like a fridge.

That is a very good point regarding the circuit that my bass amp is on. I'll check that path out. Also the monster conditioners or others.

When I said I went to town on shielding another bass, I put copper across the bottom exposed poles of the pick ups, pick up cavities, of course ground wires looping it all together. I'm just not convinced its needed on this Nordy because I think it's conditional, just haven't found the root cause yet.

It was dead silent today - fully cranked.

chinjazz · #11 01-15-2012, 04:34 PM

Quote:

Originally Posted by SGD Lutherie

No, it wont do that. I totally shield my pickups, and there's no difference in tone.

What will change the tone is if you wrap foil around the coil so that it forms a closed loop. That will remove some high end.

So just shield the PU cavities/ground?

guy n. cognito · #12 01-15-2012, 04:36 PM

Quote:

Originally Posted by chinjazz

So just shield the PU cavities/ground?

Thats correct.

SGD Lutherie · #13 01-15-2012, 04:37 PM

Quote:

Originally Posted by chinjazz

So just shield the PU cavities/ground?

yes.

guy n. cognito · #14 01-15-2012, 04:40 PM

Jazz Shielding Pictorial (Big Images Warning)

Massive sticky on this very issue.

lowsideonacurve · #15 01-15-2012, 04:48 PM

Quote:

Originally Posted by chinjazz

So just shield the PU cavities/ground?

I'd shield the control cavities, tunnels the wires run through and the underside of the pick guard too., (basically everything.)
The factory shielding paint on my Squier fretless Jazz didn't do much, so I tried the aluminum foil tape and that helped, but not enough, so I took it out and put in the copper foil tape and what a difference!
Spring for the copper tape, it makes the shielding paint and aluminum look bad.

chinjazz · #16 01-15-2012, 05:01 PM

Quote:

Originally Posted by lowsideonacurve

I'd shield the control cavities, tunnels the wires run through and the underside of the pick guard too., (basically everything.)
The factory shielding paint on my Squier fretless Jazz didn't do much, so I tried the aluminum foil tape and that helped, but not enough, so I took it out and put in the copper foil tape and what a difference!
Spring for the copper tape, it makes the shielding paint and aluminum look bad.

This is a Nordy vJ5 and everything is shielded/grounded, except for the PU cavities. By thanks for the advice.

SGD Lutherie · #17 01-15-2012, 05:07 PM

Quote:

Originally Posted by chinjazz

This is a Nordy vJ5 and everything is shielded/grounded, except for the PU cavities. By thanks for the advice.

Does Nordstrand shield their pickups? I think they only ground the magnets.

SurferJoe46 · #18 01-15-2012, 05:20 PM

Perhaps a sidebar here::

This house we moved into in Montana didn't have modern wall switches in it, so I converted those that operate overhead lights to dim-able units.

Then the fun began!

In any position from full ON to very very dim, they buzz in my shielded basses. Never mind that I have a Furman power unit and all my basses are very well shielded, they make noise.

This isn't 60~ hum either - it's a raspy racket that is there all the time the dimmers are actually ON to any degree at all.

Is it RFI, EMI or stray mutagenic Gamma Rays - I dunnow!

chinjazz · #19 01-15-2012, 05:23 PM

Quote:

Originally Posted by SGD Lutherie

Does Nordstrand shield their pickups? I think they only ground the magnets.

Not exactly sure, but I've got an email chain going with them, and I'll ask.

chinjazz · #20 01-15-2012, 05:26 PM

Quote:

Originally Posted by SurferJoe46

Perhaps a sidebar here::

This house we moved into in Montana didn't have modern wall switches in it, so I converted those that operate overhead lights to dim-able units.

Then the fun began!

In any position from full ON to very very dim, they buzz in my shielded basses. Never mind that I have a Furman power unit and all my basses are very well shielded, they make noise.

This isn't 60~ hum either - it's a raspy racket that is there all the time the dimmers are actually ON to any degree at all.

Is it RFI, EMI or stray mutagenic Gamma Rays - I dunnow!

Yeah, I've had a few fun moments with riostats at my old house.
That's not an issue here.