bill lawrence L500 trouble

[copperheadroads]

i got a L500 blade humbucker in a guitar for about 15 years now i hasn't used it for a couple of years ,but when i fired up today it sounded really muddy so i ended up replacing it with another pickup i checked it with my meter it read 8.4k . i checked the individual coils they were around 4.2k. I'm pretty sure this pickup was around 11 to 12 k i guess there's not much you can do with it .its a epoxy sealed pickup

[Dave Kerr]

Sympathy pains?

[kevinT]

i got a L500 blade humbucker in a guitar for about 15 years now i hasn't used it for a couple of years ,but when i fired up today it sounded really muddy so i ended up replacing it with another pickup i checked it with my meter it read 8.4k . i checked the individual coils they were around 4.2k. I'm pretty sure this pickup was around 11 to 12 k i guess there's not much you can do with it .its a epoxy sealed pickup

I believe the L500 should have a higher DCR. Probably a short somewhere..

[MKB]

That's strange that both bobbins shorted out. IIRC the neck pickups had a lower DCR than the bridge, but it has been years since I saw one.

You can remove coils from potting, but you have to be extremely careful and hope the epoxy didn't soak the coil too much, and the builder taped the coils prior to potting. I successfully unpotted a Gibson Super Humbucker from a seventies LP Custom and reused the coils. Some potting epoxies tend to become crumbly when heated, so you take a heat gun and dental picks, heat the epoxy and flake it off until your coils pop out.

It might be harder or impossible to unpot a L500 as those have plastic bases IIRC, and the plastic may melt while you are trying to heat the epoxy.

[Robert M. Martinelli]

i got a L500 blade humbucker in a guitar for about 15 years now i hasn't used it for a couple of years ,but when i fired up today it sounded really muddy so i ended up replacing it with another pickup i checked it with my meter it read 8.4k . i checked the individual coils they were around 4.2k. I'm pretty sure this pickup was around 11 to 12 k i guess there's not much you can do with it .its a epoxy sealed pickup

It depends on what version you have, AFAIK the L500 used to be available in three "grades", L500R, L500L, L500XL, the R version was intended to be used in the (R)ear position, so its DC resistance, inductance ( and stray capacitance ) are low compared to the L500L(ead), which was intended to be used in the bridge position, and the L500(e)X(tra)L(ead), a "souped up" version of the L500L(ead).

I once measured an L500XL's electrical constants, and its DC resistance ( coils in series ) was around 15K, its inductance about 9H, and the stray capacitance some 70 pF.

I'd bet what you have is a "standard" L500R...Since the coils do exhibit the same DC resistance, I don't really think they're shorted/defective (it's highly unlikely that they've suffered the same kind of damage at the exact same point of the winding IMHO).

Hope this helps

Best regards

Bob

[Joe Gwinn]

Hot knife for removing epoxy

Some soldering iron makes can be fitted with a knife tip, intended for use as a hot knife, which will make short work of epoxy without melting everything nearby.

For instance, the Weller WES51 iron accepts the ETKN tip.

One can also make knife tips from standard tips.

[David Schwab]

Lawrence actually used polyester resin in the pickups.

I disassembled a closed cover Lawrence pickup that I had since the mid 80's. One coil had gone dead.

I couldn't do it with heat, so I had to chip it apart.

The L-500 has a closed bottom plastic cover, so there's no practical way to get one open without destroying it.

[Vihar]

the R version was intended to be used in the (R)ear position

Just a small correction: not "Rear", Rhythm. The rear pickup is the lead one. lol

[copperheadroads]

i emailed them .they said a L500 lead/bridge pickup is about 8.2 k and the L500XL is 11-12K so i guess im wrong .i put it in the neck position to try it, it sounds great. in the bridge playing down the neck below the 12 fret it sounds like you got a wah pedal turned on

[Robert M. Martinelli]

Just a small correction: not "Rear", Rhythm. The rear pickup is the lead one. lol

Sorry for that - sometimes thinking and typing seem to be a world apart
( hope the point I was trying to make was clear enough ).

Cheers

Bob

[Robert M. Martinelli]

i emailed them .they said a L500 lead/bridge pickup is about 8.2 k and the L500XL is 11-12K so i guess im wrong .i put it in the neck position to try it, it sounds great. in the bridge playing down the neck below the 12 fret it sounds like you got a wah pedal turned on

That confirms my thoughts about your pickup being an L500(R) in good working order.

Now, about the e-mail they sent you, I find it strange that they say the L is 8,2 K and the XL is 11-12K, I'm pretty sure about the XL specs I gave in my previous post, ( 15KOhm, 9H, 70 pF ) so I guess they were referring to the "R" and "L" version respectively.

It's very strange that the pickups sounds "good" at the neck and "bad" ( muddy ) at the bridge, are you sure there are no caps connected to the bridge position and acting as filters? If the pickup sounds muddy at the bridge it should sound muddier at the neck....

Cheers

Bob