Noisy Gibson lap steel

[Rhodesplyr]

A friend of mine has a 1950s Gibson BR-6 lap steel and has asked for my help in seeing if anything can be done about how noisy it is. It has its original single-coil pickup, and it's extremely susceptible to any ambient fields. I've checked it out thoroughly, and there are no wiring problems. He wants to use it for studio recording, but it drives engineers nuts.

He's done an excellent job of lining the pickup cavity and cover with copper, but, as we know, this doesn't stop magnetic fields. Interestingly, it hums/buzzes the least if you hold it in a vertical plane. The only thing I could do that cut the noise was holding a large sheet of steel over the pickup area--not very convenient.

He wanted me to swap in a Strat pickup, but it didn't really fit properly. (Mounting was a problem, and the poles didn't line up with the strings.) If we were to find one that mounts reasonably well, are chances good that a modern single-coil would be less susceptible to noise pickup? Any recommendations for brands/types?

Or would he be better off finding a different lap steel? I'm a keyboard player, so I'm not up on all the finer points of pickups.

[ric]

Hi Rhodes-I have had a similar problem when I reversed the leads on a Tele bridge p/u to have it in phase with a neck p/u I was trying. I didn't realize that the bridge p/u's plate was connected to the common wire. When I reversed them it was then attached to the hot. Moving the plate connection to the new common took care of it. You could meter around in the p/u cavity and see if you find any thing in there- shielding, base plate, a pots back or anything that has continuity to the signal. HTH. -ric

[big_teee]

Sounds like you need a humbucking pickup.
A Blade pickup, or Sidewinder hum canceling pickup would work.
T

[rjb]

The only thing I could do that cut the noise was holding a large sheet of steel over the pickup area--not very convenient.

Does the BR6 have a full guard that covers the pickup, like this:
http://www.vintageguitars.fr/details...54-detail3.jpg

Or a partial guard, like this:
http://www.vintage-strings.co.jp/images/s1010_4.jpg

If your friend has one like the 2nd image, could you fabricate a guard similar to the 1st image?

He wanted me to swap in a Strat pickup, but it didn't really fit properly.

In general, lap steel string spacing is wider than guitar spacing- you'll either have to find a lap steel pickup, have one made, or build one yourself.

Welcome to the club.

-rb

ps- Big Tee has done some work with lap steel pickups lately (hint).

[Rhodesplyr]

This BR-6 has the full guard, and both the cavity and the guard have been very nicely covered with copper foil, connected to the main ground.

[big_teee]

Could you show a pic of the body cavity.
Might give us some more insite on what to do next?
Are you playing the lap steel real close to the amp?
Is there shielded wire, or regular wire inside?
Are you playing near flourescent lights, light dimmers, etc?
Doe it act this way in other areas, with other amps?
I would try to process and eliminate everything you can.
GL,
T

[Rhodesplyr]

My friend has his lap steel on a short tour, so I won't be able to get to it again for a couple of weeks.
No, the lap steel is not being played close to the amp. I'm not quite that clueless :-)
The wiring inside the lap steel is dead-stock with ancient shielded coax.
He's playing it live on gigs, so he could be around any number of ambient noise sources depending on the venue. It's a consistent problem.
It acts the same way everywhere with different amps.

The only thing I haven't explored is the possibility of multiple ground paths inside the lap steel. Assuming that the original pickup shield is non-conductive, the addition of the copper foil shielding (nicely done) created a new ground path between the tone and volume pot bushings, so there is definitely a small loop in the ground since these pots are also grounded via their shells. However, its owner says that it did not become noisier after adding the foil shielding.

[Paleo Pete]

You said single coil pickup, singular, so I'm guessing it's the same as mine, WWII era Electromuse with a similar single coil. No noise from mine, or very little anyway, even before I replaced the soldered in cloth covered guitar cable.

The one thing I see from your comments is the guitar is wired with "ancient shielded coax". Replacing that might help, if possible.

Also does it have a capacitor between volume and tone pots as mine was set up? Mine had an ancient "domino" cap, bass player hung his foot on the cable one night and yanked it off the guitar stand, replacing cable left it still very noisy, replacing the cap solved it. I really hated losing that old cloth covered cable too...All I had done was replace the jack. And squirt some contact cleaner in the pots, sounded fabulous. Got it back to usable condition now but I think next string change I might swap the cap for a different value to cut back the treble a bit.

Anyway consider the cap, or adding one, and if possible replace the old shielded cable. If it's ever been dropped or the cable yanked it could have either a bad cap or a bad spot in the shielding.

Just for fun here's mine before the cable was replaced.

[big_teee]

Sorry, not trying to insult anyone, I always start at the beginning. lol
Like Pete said, I would give it a total rewire.
I just did that on a Jap made import 335 type hollow body for a customer.
It was terribly noisy, and after I rewired it all with the small shielded cable it was dead quiet.
Check and make sure the bridge ground didn't come loose.
I like to hook the ohm meter to the sleeve of the guitar cable plugged in and read to ground all around on everything.
Making sure it reads low ohms.
I bet you will figure it out.
GL,
T

[Audiotexan]

I've long been a fan of the Seymour Duncan STK-1's (noise-cancelling dual coils stacked in a single coil config) that came stock in my Jackson DK-1. Great tone, no noise.

Evidently though they've been discontinued, and it seems the closest thing I can find with the same config is the PA-STK1 Seymour Duncan PA-STK1 Parallel Axis Stack Single Coil - neck/middle. There's a pic in that link that shows the stacked coils that I'm referring to. http://www.macdaddymusicstore.com/me...b11541bd_l.jpg

No clue how the PA-STK sounds.. but I love the originals from 97! Might give those a go if string spacing is close, and I'm sure they can be found on ebay or similar with a little diligence. At least it'd be a whole lot cheaper than having one rewound/custom built.

GL!

https://www.youtube.com/watch?v=J0BFwkj98TI

[rjb]

Yea, what them other guys said.

I, too, cast my vote for rechecking the stock wiring for ground discontinuities... or saving time by just replacing the coax and cap!
IMHO, the hum is far more likely to be caused by rusted/busted coax shielding or a cracked cap than by a ground loop.

Please report back after you've solved the problem.

-rb

OFF-TOPIC Regarding the Electromuse:
FWIW, I don't think the pickups are all that similar.
Going by what I've read, the BR-6 pickups are similar to P90s.
The Electromuse "Eye-Beam" pickup is a chunk of I-beam shaped alnico, wrapped with a few turns of wire.
I think the low turns count makes the Eye-Beam less susceptible to noise than other single coil pickups.
I've rewired an Electromuse and rewound the (open) pickup.
Stock, the volume pot is 21K (vs 250K typical for Fender SCs or 500K for P90s), and there is not much wire wrapped around the magnet.
I filled the available space with about 2300 turns of 38 AWG, for a DCR of 600 ohms. That's probably more turns than the original winding.
It is the quietest single coil pickup I've plugged into an amp- and more powerful than you might expect.
The ferrous hand rest is part of the magnetic circuit; it spreads the field and balances it on either side of the string, increasing volume and sustain.
Or something like that.
Anyways, I think Electromuse pickups are probably inherently more quiet than BR-6 pickups.
For what it's worth.

[Steve A.]

#1. As a lap steel the BR-6 has wider string spacing than a regular which rules out dropping in any other pickup (besides perhaps a 7 string pickup with a blade.) It also is wider than most other lap steels so I doubt that an Electromuse pickup would work.

#2. A steady hum or buzz can be digitally removed from recordings very transparently. You take a sample of the noise and the noise reduction plug-in will subtract that waveform from your guitar track. The trick is to set it moderately to reach a noise level that you can live with. (If you set it to 100% it will sound artificial.) My instructions refer to Adobe Audition 3.

#3. IMO dummy coil following the Chiliachki patent would be the best solution. (I've been experimenting along these lines with mixed results. The larger the circumference the better the dummy coil would work (routing a channel under the removable plastic fretboard might work perfectly.)

http://www.blueguitar.org/new/misc/p...chiliachki.pdf

Gibson used 5 or 6 different pickups in their BR-6's so posting a photo would help. Along with the string spacing measured right at the pickup.

Steve Ahola

P.S. One other option- send it in to Pete Biltoft at Vintage Vibe Guitars to be rewound. He does a great job and keeps the noise of a single coil down with shielding (and whatever other tricks he uses!)

Vintage Vibe Guitar Pickups: Assorted Pickups

P.P.S. Where I live single coil lap steels hum a lot because of their horizontal orientation. With a regular guitar you can usually rotate around until the noise is minimized but you don't have that option with a lap steel (unless you don't mind playing it at a 45 degree angle to the floor.)

P.P.P.S. If your friend doesn't mind changing the appearance of his BR-6 he could have a custom pickguard/pickup cover made that will accommodate a George L E-66 pickup (all of his pickups are humbucking.)

George L's Pickups

[Steve A.]

Here is an earlier thread on BR-6 pickups...

http://music-electronics-forum.com/t17349/

Steve

P.S. The BR-9 was the last lap steel that Gibson made that looked like a guitar rather than just a plank of wood.

P.P.S. That thread from 2011 has a post from Jason Lollar

that's a special size pickup with a special mounting plate- I make them but don't list them on my site , call the shop unless someone else would rather do it.

[rjb]

It also is wider than most other lap steels so I doubt that an Electromuse pickup would work.

AFAIK, no one suggested using an Electromuse pickup. They're probably harder to come by than BR-6 pickups, and not a drop-in replacement in anything but Electromuse lap steels. They're also tonal opposites (pristine bell-like clarity versus gutsy P90 tone). Plus, they need a 21K volume pot.
I did contend that EyeBeam pickups are inherently quieter- only because Paleo Pete characterized them as "similar" to BR-6 pickups, and I don't think they really are.

... custom pickguard/pickup cover...

Which prompts a "just curious" question:
What material is the original pickguard/pickup cover made of?
It seems to me that a steel cover would provide shielding, plus increase output and sustain.
But in the photos, it looks like some kind of plastic....

[Steve A.]

Looking at the picture the pickguard/pickup cover is the plastic piece which covers about 80% of the lower bout. It could be lined with tin foil over the pickup and wiring. Gibson used "metallized cardboard" in the control compartment of my 1948 Century 6. Like chipboard with aluminum foil glued to it.