Weird problem with new SG

[foghorn]

The good news: After a lot of hemming and hawing over models, I secured a new Pelham Blue SG special and love everything about it. The neck, the P90's, great playing/sounding/looking guitar.

The bad news: Yeah, it has an intermittent problem.

On about the 3rd day, I was playing with the switch in the bridge position and suddenly the sound died. I also noticed when I moved the switch to middle, when I rolled the volume to 0 on the neck pickup, I still had sound which is obviously wrong. Zero volume on neck pickup shut volume off as it should. (I might have this reversed...can't recall). Wiggling switch in middle position produced noise. After a minute or two the problem went away but I found a local tech (I live hours way from any "Gibson authorized" repair shops) and he took a look, went through the entire guitar, found "nothing wrong", and blamed my cord. Took the guitar home but a few days later it happened again.

At this point I called a couple friends and we decided the likely culprit was the switch. I took off the back cover (a chore in itself, another long story) and I sprayed the points on the switch with contact spray. After that, for 7-8 days the guitar was fine, then it happened again only this time the symptoms were "slightly" different: The sound didn't immediately "cut out" but sort of bled away, like the air going out of balloon, seemed to take a couple seconds. (NOTE: this MIGHT have been the case the first time as well but then I was playing through an amp, the subsequent times have been through headphones playing into an interface box, so maybe I'm "hearing" the sound die whereas I wouldn't have through the amp?). Futzing with the switch/unplugging and replugging the cable eventually sets things right and I go on my merry way. Played it for another week, happened again last night.

So far the issue has occurred with switch in treble or middle position, never neck. "So far". I'm not even entirely convinced it's the guitar at this point (possibly interference, a voltage issue, who knows?) although it probably is. I'll try and attach a photo of the inside, everybody who has looked at it doesn't see anything weird.

Any ideas? At this point, I'm at a loss.

 

[Grizzlyman]

If it’s new I would return it.
Sounds to me like a faulty bridge pickup…

 

[foghorn]

Here's the photo...

 

[JimH]

I had a new Les Paul that had a similar problem. I found that the braided shielding from one of the pickup wires was making contact with one of the pots, causing the signal to cut out. Maybe double check the control cavity for something like that.

EDIT: the photo didn't load until after I posted, so I guess it's not what I mentioned.

 

[foghorn]

Thanks Grizzlyman....do you know if there is some sort of "definitive test" I could have my tech perform to confirm a bad pickup? Obviously I can ask him as well. (Unfortunately at this point returning the guitar isn't an option).

JimH, it actually looks like braided wire IS hitting upper right pot (or could be)..But it sounds like you think mine looks ok? Sorry I'm a complete dummy when it comes to guitar electronics...

 

[cerebral gasket]

Outer braided shielding = ground
Inner black insulated wire = hot

Those two should never touch each other or sound will cut out.

The solder blob over the pup leads on the back of the neck pup volume pot looks to be suspect.

There is solder covering the black insulation of the hot wires to the pups. If any of that black insulation got burned away during the soldering process, the bare hot wire may be touching the outer braiding or solder causing a short to ground resulting in either intermittent or no sound at all.

Avoid solder at the transition where the inner black hot wire insulation exits the outer shielded braided wire which is ground. Solder only the outer braided shield to the back of the pot casing.

To test the pup, use a multimeter to measure the resistance between the hot and ground leads of the pup which should be around 8kΩ for a P-90.

 

[foghorn]

Thanks cerebral! Even to my untrained eye it looks like a sloppy soldering job.

I'm looking at your photo and only see one braided wire with one black insulated exiting whereas I seem to have 2 so a little confused there, but in any case you specified the outer so I know where to look. Looks like I need to scrape off some solder to see whats going on but what you said makes sense. Also I assume since these pups are wired in series if it is a bad connection it could effect the treble pup and not neck. When this happens it's always after I've been playing a while....maybe the minute amount of heat generated (if any) might coax the hot wire to touch ground whereas when it's "cold" if doesn't? Just a guess. Thanks again for this info!

 

[cerebral gasket]

The two coils of a Humbucker are wired in series with each other. Neck and Bridge pups are wired in parallel with each other when selector switch is in middle position.

Some dual pup guitars have both braided shields soldered to same pot and others are wired to separate pots. Does not matter since both are ground.

Main thing to look for is short between hot and ground wires.

 

[papagayo]

Did you try the guitar without the controls plate? Some times the jack touck the plate.

 

[laza616]

When you switched to the bridge pup, the sound died and then when you went to the middle position and turned the volume pot on the neck pup to 0 and you had a sound
But was it a neck pup you were hearing or the bridge one? Do you even hear crackling while switching?

My bet would be poorly soldered switch to the cables / maybe these soft wires are broken and the contact is wonky.

You bought a very good guitar that will be with you for the rest of your life, or until you sell it. Anyway, this is an instrument that is worth spending some quid on it. I know its under the warranty and they should be fixing it for you. If it was my case, i would have taken the guitar not to some local tech who assumed you have a bad cord. Bad cord my ass. But i would have the guitar taken to the skilled luthier to have it pro fixed and set. Yeah Gibson should have done that in the factory, so that leads me to the question how they checked it
Buy maybe, maybe its just that they didnt pay any extra attention and you were just unlucky that from the thousands of guitars that Gibson produces, you took the one that wasnt 100% flawless. Still its no excuse
To be honest, looking at the photo of your cavity, this is quite a lousy soldering and cable job.
It looks like a friday afternoon production or some novice worker had a shift and put a little effort to it

Anyway, send more photos of that axe!

 

[Huntroll]

The leaf switch needs adjustment.
You can see a gap between the lower set of points.

 

[Colnago]

It sounds like a grounding issue where something is intermittently touching something it shouldn’t be.
What’s the problem with the back plate?

 

[cerebral gasket]

It sounds like a grounding issue where something is intermittently touching something it shouldn’t be.

Or an open circuit where something is not touching something when it should be like the gap on the switch contact to the bridge pup.

 

[cerebral gasket]

Did you try the guitar without the controls plate? Some times the jack touck the plate.

The control cover plate is plastic.
Plastic is an insulator.

 

[foghorn]

When you switched to the bridge pup, the sound died and then when you went to the middle position and turned the volume pot on the neck pup to 0 and you had a sound
But was it a neck pup you were hearing or the bridge one? Do you even hear crackling while switching?

Unfortunately, I don't recall which pup was sounding. Yes there was crackling which is now gone ever since I sprayed the switch contacts.

If it was my case, i would have taken the guitar not to some local tech who assumed you have a bad cord. Bad cord my ass. But i would have the guitar taken to the skilled luthier to have it pro fixed and set.

Well, I didn't know I was going to get the "it's the cable" response until after he went through the guitar and found nothing. I didn't know this guy but he was close by and seemed reasonably competent. For the record, I live more than 2 hours from the nearest "Gibson authorized repair" dealer and when I called them he said they would have to charge me because I didn't buy the guitar from them. This sounded crazy so I called Gibson and they verified this - it's entirely up to the store whether they want to take on a repair. Sounds crazy but that's what he said. Lastly, I of couse could have returned the guitar immediately upon finding an issue. But frankly I thought thisi would be an easier fix, and the Pelham Blue's were already becoming scarce (there is now another thread here claiming the run is over) so these are some of the reasons I took the course I did, right or wrong.

The leaf switch needs adjustment.
You can see a gap between the lower set of points.

Yes. I noticed the bridge points look funky and so did my two buddies who looked at the photo. To me it does appear they "make contact" but it's really close...maybe a slight bend on the inner arm to angle it in slightly would do the trick. But it does seem odd that when it does crap out, it isn't always right away after I've made a change to the switch position, it can be a few minutes later...

What’s the problem with the back plate?

It's an extremely tight fit and a bear to get off. You can see where they probably oversprayed the finish. I've already gouged the plate twice trying to pry it off and I've been avoiding taking it off again lol. But it's obviously inevitable.

So yes, between the plate and the wiring/soldering/switch....pretty dissapointed with the shoddiness of workmanship. But I love the guitar overall, just want to solve this issue and play the hell out of it without worry.

 

[Norton]

the joint from the switch to the bridge volume control pot (yellow wire/ground) looks like it could be a cold joint.

Cold joints, intermittent connections between braided shielding and the hot signal and switch issues can all show themselves in the way you're describing. Also, bad pots and internal pickup faults can do the same thing. Have you put a meter on the bridge pickup?

I'd check all the "obvious" spots first... and if that doesn't fix the problem, I'd suggest a careful disconnect and re-wire.

That braided shielding on the pickup leads can be very sneaky and troublesome if it's not super neat and clean.

I'd definitely let gibson know about it... and the retailer... but man I would NOT send it back to the factory for such a simple fix.

 

[foghorn]

Thx, I'll check the yellow wire when I go back in. The tech put a meter on both pups and they read in the high 7's (I can't recall the exact number). I'm ordering a multimeter anyway since mine crapped out so I'll recheck.

Yeah, at this point the approach I'm going to take is slow and methodical as possible, attempting to remedy the most obvious (of which I'm not sure there is!) and easiest fixes first. I ordered some deoxit fader spray so I'll hit the pots and I'll double check the switch points making contact in all positions. I'm still considering a light sand (600 grit?) on the points but I've heard arguments against doing that so I don't know. I can have my daughter strum the guitar while I slowly and gently try and move wires (a slight bit) to see if I can recreate the issue.

If I'm still out of luck after all this I guess I'll have to tackle the solder mess on the neck volume pot....I have a friend who can help me since my soldering skills are about zero.

Thanks for all the input everyone!

 

[foghorn]

oh yeah somebody wanted a photo. It is sharp looking I have to admit...

 

[Col Mustard]

Welcome to ETSG!
That Pelham blue guitar is lovely... What to do...

It all comes down to how much you love this guitar.
Me, I tend to bond with my guitars, whatever they are. Once I've got
them in my clutches, I tend to fix what ever is wrong with them and
then rock. Call me a guitar slut... I don't care. I tend to love the
one I'm with.

If the guitar were mine, I'd be in love with it. So here's what I'd do...

1. This sounds like a warranty issue on a new guitar... I'd take it to a genuine luthier who is approved to do Gibson warranty work,
and get the guitar re-wired. If he won't bill Gibson for it, I'd pay
him myself. So I could play music on my new Pelham Blue SG.

The object of the game here is to get the guitar re-wired
by someone who knows what they are doing, and get the pickups
checked to make sure their wiring is ok. I don't tend to fuss too
much about stuff like this. I tend to fix it and take it home so I can
play music.

2. If that's not possible, I'd buy a high quality wiring harness and
install it myself. Only a few solder joints to do this way. I can solder
the connections, but I'm not an expert at it. So I'd rather pay a bit
and get good quality parts... I just want it to work right so I can
play music. This voids the warranty, but we've already established that
the warranty isn't any good to you anyway.

3. After all this hassle, I'd get the instrument set up by the best luthier
I could find or afford. Setup is crucial to your enjoyment of your new
guitar (after the electronics are corrected).

4. rock that sucker...

Oh yeah, but since it all comes down to how much you love this individual
guitar... If you don't care about it so deeply, and if you think that one SG is
as good as another, then return it as defective and get some other guitar.
I don't recommend this, it would break my heart. I recommend you fix the one
you love, and then play music.

 

[foghorn]

Col

I love the guitar. I've had 5 SG's in my life and I have to say, "overall" (assuming I can fix it), this is my favorite - I've had two I wasn't much impressed with, so yes I'm keeping it...and returning it really isn't an option anyway at this point.

I'd be happy to have a "genuine luthier" fix this thing at Gibson's expense but besides travel being a huge issue for me, the next 3 "closest" authorized places (other than the one I mentioned in a previous post) are Guitar Centers. I "might" get lucky but I really don't trust their work all that much and I'd hardly call their techs "luthiers". I'm also pretty convinced I'd be paying for any repair, I've scratched up the back plate and of course long ago removed the plastic on the pickguard so there are light scratches there, etc.

I think I'll try a "one step at a time" approach rather than just have the whole thing rewired, even though in the end that might be more of a PITA to find the problem. I'm keeping my fingers crossed I'll get lucky and find it soon.

But I agree, I'm a player and don't obsess about wiring perfection as long as stuff works. And I want to play this thing. The irony is, I can. I have stints of over a week where it's behaved. But you know the gremlin is coming back to bite me again lol...