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 Pickups & Electronics Issues in a Used G&L L-2000? 
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Joined: Tue Jul 24, 2012 2:53 pm
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Post Pickups & Electronics Issues in a Used G&L L-2000?
Hey Guys --

I just bought a used G&L L-2000 on e-Bay (for $850), and -- while I like the tone -- I'm trying to figure out if the electronics are doing weird things.

For starters, the instrument was modified with a single coil option (there's now a 3-way series/single/parallel toggle instead of just a 2-way series/parallel switch). I like the idea of this feature, and like the single coil tone, but here's one possible issue. With a one pickup or the other selected, the instrument is suitably quiet in parallel mode, and expectedly noisy in single coil mode. But what I don't get is that it's just as noisy in series mode as it in in single coil. Is that to be expected? Maybe I don't understand something basic about pickup circuitry, but I would've thought that series mode was still humbucking and would be quiet. Incidentally, when both pickups are on and single coil mode is selected, the two single coils cancel out the hum, just like on a Jazz bass. Anyway, that's problem number one (if it's a problem at all).

The second issue has to do with the active electronics. Namely, I get an unacceptably loud "Pop" when I switch from passive to active mode. This isn't normal, is it?

Finally, once I'm actually in active mode, the signal seems to be so hot that it's unusable. I know these basses are known for hot pickups and a very hot pre-amp. Am I right to assume that the bass is clipping the input stage of my recording chain -- a Demeter Tube Direct Box? Or does this sound like a problem within the pre-amp's own circuitry? Turning down the instrument's own volume seems to eliminate the clipping, but then it's a pretty anemic signal coming out of the bass.

I'm not sure I need active mode anyway, but would love some opinions about this issue -- and the parallel mode noise I mentioned, too.

It seems like a really nice instrument provided I can get the electronics performing the way they should.

Thanks in advance!

Alan


Tue Jul 24, 2012 2:58 pm
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Location: Near Annapolis, Maryland, USA
Post Re: Pickups & Electronics Issues in a Used G&L L-2000?
Alan,

Hopefully Ken Baker will see this thread and weigh in. Untilhe does, I will take a stab at it.

My 2000 L2K has none of the problems you describe. It has the stock circuit. It's fretless, but that shouldn't make a difference aside from the attack and decay of the notes and maybe a slight loss of high end compared to fretted basses.

I have no significant changes in volume between different switch positions, even on the passive/active/treble boost switch. Others could do a better job of explaining the details, but the preamp in these G&Ls isn't intended to give a massive boost to the signal. It's true that the pups are hot, but judging by my L2Ks they are equally hot in all positions. My other L2K is an early one and has the original circuit, but it still responds in basically the same way - just a touch more thunder on the low end in certain settings.

None of my G&L basses (or guitars for that matter) pop when I change settings. This may be a problem with the switch, or possibly the mods done by the previous owner.

FWIW, I would try going back to the stock L2K circuit and decide from there whether you need any mods. These are incredibly versatile basses, so between the instrument and amp settings you should be able to pull off all sorts of styles. Of course, YMMV.

One other relevant bit of information is the year your bass was built, as there have been a couple of minor circuit changes along the way. The earliest ones came in two models, the L-2000 and L-2000E. These were from '81 to (I think) early '82, and had front loaded controls with a chrome bridge and control plate. The passive version went away around '82 (the "E" was dropped from the model name at the same time) and the body hardware got a black plating. There was a change to the circuit around '84, and a change to rear-loaded controls in the late 80s. I can't remember whether the circuit changed with the introduction of rear-loaded controls. Obviously, the answers about your circuit may be a little bit different if you have one of the older versions.

I hope this helps!

Ken C


Tue Jul 24, 2012 5:27 pm
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Post Re: Pickups & Electronics Issues in a Used G&L L-2000?
Thanks, Ken -- I appreciate the thorough response. My L-2000 was apparently built in 1999, for what that's worth. I don't have any info about the mods that were done, other than knowing that the single coil option was added. Again, I do like that. Anyway, I think that's the only change that was made. I just can't figure out the noise I get in serial mode, as opposed to parallel mode (which is reasonably quiet and seems to be properly humbucking).

Anyway, thanks again!

Alan


Tue Jul 24, 2012 6:18 pm
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Post Re: Pickups & Electronics Issues in a Used G&L L-2000?
Actually, in case anyone is inteested, I just came across a Talkbass.com thread started by somebody who'd had the same problem -- excessive noise while in series mode. I'm not sure if their noise was the quite the same as mine, but here's what was suggested:

The loud hum is due to the two big green capacitors connected to the series/parallel switch. Supposedly they put them there to reduce the output of the series mode so it's not a lot louder than parallel but it mostly adds noise. I desoldered them from the back of the pot on my L-2000 and series is super quiet now. It does make series louder but I don't use parallel that often so that didn't bother me. It's a reversible mod, try it out and if you like how it sounds make sure you put tape or insulation on the wires you took off the pot so they don't ground somewhere else when you put the cover back on.


Tue Jul 24, 2012 8:09 pm
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Post Re: Pickups & Electronics Issues in a Used G&L L-2000?
It sounds like your bass has the "K" wiring which G&L does for all L-2000, L-2500, and ASAT Basses
sold to the Japan distributor. See the L-2000K, L-2500K, and ASAT Bass K Picture Diagram in our Gallery.

Hope this helps.

:ugeek:

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Tue Jul 24, 2012 8:28 pm
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Post Re: Pickups & Electronics Issues in a Used G&L L-2000?
Thanks for the responses. Is it standard that, in signal coil mode with both pickups selected, I'd get a humbucking effect like on a J-bass, where the bridge and neck pickups are wound reverse directions? That seems to be happening on my L-2000.

On a related note, I'm still trying to figure out why, when just one or the other pickup is selected, serial mode is every bit as noisy (in terms of picking up interference) as single coil mode, but parallel is nice and quiet. Should I be counting my blessings? On my Jazz Bass, single coil operation is often unacceptably noisy, but on the L-2000, it's totally workable. Some of these issues are making me wonder if the supposed single coil mod is actually doing its thing.

I read on Talkbass.com that the single coil mod still achieves a certain amount of humbucking effect due to the way the defeated coil still interacts with the live one. Any thoughts on this?

Tnanks again,

Alan


Thu Jul 26, 2012 5:35 pm
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Post Re: Pickups & Electronics Issues in a Used G&L L-2000?
I just lost a post. Apologies for posting twice if it somehow shows up!

Hey Alan,

I suggest trying BassesbyLeo.com, the low-end counterpart to the G&LDP. They just talk G&L basses over there, and tend to get pretty heavily into circuitry and mods. There's a good chance the mod you mentioned either originated there or has been discussed there in detail. I bring this up only because you probably have a better chance of getting a quick, thorough answer over there. If I remember correctly, they have an archive of G&L bass mods and a topic page devoted completely to G&L bass mods. Please keep this thread going and let us know what you find out if you do check over there!

Ken Baker is the BbL moderator. He visits here frequently and joins in most of the bass-related discussions, but it seems like he's been away lately.

Ken C


Thu Jul 26, 2012 7:10 pm
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Post Re: Pickups & Electronics Issues in a Used G&L L-2000?
Thanks, Ken. I'll check it out. Why are all of you G&L guys named Ken?


Thu Jul 26, 2012 7:35 pm
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Post Re: Pickups & Electronics Issues in a Used G&L L-2000?
ADWolpert wrote:
Thanks, Ken. I'll check it out. Why are all of you G&L guys named Ken?


Because it's a damned fine name! :mrgreen:

I see a little more info here, specifically that it's a 1999 L-2000. That's not early enough to have had the caps you found installed at the factory. It was probably a mod by someone look to add OMG mode, AKA "Bass Boost" (which is a whole 'nother story). I see you've lifted them and found quiet. Series being louder than parallel is normal.

The "K" model basses come from the factory with single coil mode capability. While they can be ordered now (it's off-menu but available), they were rare in 1999. As to whether or not it's a "K" model, you can tell by looking for blue leads from each pickup connecting to ground. If this is a "for USA" bass, it's probably been modded and will not have the blue leads. If it is a "K" model, it's either a rare USA version or brought back in from Japan.

Ken...

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Last edited by Ken Baker on Fri Jul 27, 2012 12:37 pm, edited 1 time in total.



Thu Jul 26, 2012 11:13 pm
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Post Re: Pickups & Electronics Issues in a Used G&L L-2000?
Hi Ken --

Thanks for the response here -- very helpful. Which Ken am I talking to now?
Getting advice on two separate G&L sites from two different guys named Ken gets confusing!

Actually, I haven't yet determined what caps are in the bass, if there's in fact an OMG mod, etc. And I certianly haven't removed anything yet. All I've done, really, is listen and describe the noise I was hearing. I'm gonna open up the back and take a good look (and maybe even snap a few pictures later today (it's 4:30am in NY, am I'm only up because my 5-month-old son decided I should be!).

Thanks again!

Alan


Fri Jul 27, 2012 1:38 am
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