Help. Faint volume from one pickup

lonechicken

New member
I have a standard Les Paul wiring setup with two humbuckers and a 3 way switch. The volume on the neck 59 is fine. The bridge sounds very faint, and I have to strike the strings very hard to get some sound, and even then the sound cuts out quickly. Like it's got massive noise gate turned on or is a very weak single coil. So here's what I've done with no difference:

-Swapped out the bridge 59 for a brand new Duncan Distortion
-Changed the pickup selector to a new one
-Changed the output jack
-Changed the volume pot for the bridge
-Changed the tone pot for the bridge
-Replaced old wires with brand new wires
-Raised and lowered bridge pickup
-Changed the cap for the bridge tone pot
-Used a multi-meter to check all pots and they seem normal
-Attached ground wire from bridge first to neck tone, then tried bridge tone

And of course I've checked the wiring vs. Seymour Duncan's diagrams about 100 times, and it's correct. I've never run into this problem before, and I'm kind of running out of ideas as far as troubleshooting.

Using the multimeter and touching the selector and output jack in various combinations...
Switched to bridge pickup:
-Neck to outer ring of jack 519k
-Neck to inner ring of jack 007k
-Bridge to outer ring of jack 0
-Bridge to inner ring of jack 512k

Switched to neck pickup:
-Neck to outer ring of jack 0
-Neck to inner ring of jack 007k
-Bridge to outer ring of jack 519k
-Bridge to inner ring of jack 512k

I knew I'd forget something, and it goes along with the readings. For the bridge pickup (old and new) when selected, it does this weird thing where turning down the tone will turn off the sound, but so does the normal action of turning down the volume pot.

I'm not sure what to make of the above readings. Do they even make sense the way I wrote it?
 
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Re: Help. Faint volume from one pickup

Connect the pickup directly to the jack by itself and see if that works. If not, it's the pickup.

If it works, connect the pickup to the Vol, then the Vol to the jack.

If it works, add the Tone.

If it works, run it all to the switch.
 
Re: Help. Faint volume from one pickup

Connect the pickup directly to the jack by itself and see if that works. If not, it's the pickup.

If it works, connect the pickup to the Vol, then the Vol to the jack.

If it works, add the Tone.

If it works, run it all to the switch.

I'll give it a shot.

Both the old and the new bridge pickup having this problem though? Not impossible, but hmmm...

Question, so in your suggestions, where should I hook up the ground from the jack? And where do I hook the ground of the pickup?
 
Re: Help. Faint volume from one pickup

This problem usually turns out to be some metal part of the selector switch making physical contact with the screening on the surface of the switch cavity (or the cavity cover plate), creating a short.
 
Re: Help. Faint volume from one pickup

I'll give it a shot.

Both the old and the new bridge pickup having this problem though? Not impossible, but hmmm...

Question, so in your suggestions, where should I hook up the ground from the jack? And where do I hook the ground of the pickup?

Sounds like a bad switch.

If you want to run directly to the jack -

Make sure you run the ground wire from the pickup AND from the bridge to the jack.
 
Re: Help. Faint volume from one pickup

So far...

- Pickup straight to jack seems okay as far as loudness and fullness. It's a bit noisy because I twisted the ends together instead of soldering.
- Pickup + Switch sounds about the same as above. It's about as loud as the neck pickup, though I thought the Duncan Distortion would be a little louder than the neck 59even if it's at the bridge.
- Pickup + Volume Pot seems to be a little thin. Questionable.
- Pickup + Volume Pot + Tone. Definitely something weird there. And the same problem of turning down the tone turns off the sound.
- Pickup + Volume Pot + Switch also seems questionable.

Not quite ruling anything out, but I'm thinking the problem is probably not the pickup, jack, or switch.

It would seem weird to me that two Gibson 500k pots as well as two CTS 500k pots brand new would all be bad.

Going back to the numbers in my O.P., I'd think it would make more sense if those 512k numbers were around 0 in both cases, right?
 
Re: Help. Faint volume from one pickup

So far...

- Pickup straight to jack seems okay as far as loudness and fullness. It's a bit noisy because I twisted the ends together instead of soldering.
- Pickup + Switch sounds about the same as above. It's about as loud as the neck pickup, though I thought the Duncan Distortion would be a little louder than the neck 59even if it's at the bridge.

This is because the 59 is actually closer to the strings, and the strings at that area have more vibration. Not much you can do here except use a very low output pickup (Jazz) or lower the 59.

- Pickup + Volume Pot seems to be a little thin. Questionable.
- Pickup + Volume Pot + Tone. Definitely something weird there. And the same problem of turning down the tone turns off the sound.
- Pickup + Volume Pot + Switch also seems questionable.

Then you've found the problem. Try running it to the Tone without the volume pot in the chain (pickup to Tone to jack), then to the switch to the tone to the jack without the volume.

Not quite ruling anything out, but I'm thinking the problem is probably not the pickup, jack, or switch.

It would seem weird to me that two Gibson 500k pots as well as two CTS 500k pots brand new would all be bad.

It happens.
 
Re: Help. Faint volume from one pickup

I have a standard Les Paul wiring setup with two humbuckers and a 3 way switch. The volume on the neck 59 is fine. The bridge sounds very faint, and I have to strike the strings very hard to get some sound, and even then the sound cuts out quickly. Like it's got massive noise gate turned on or is a very weak single coil. So here's what I've done with no difference:

-Swapped out the bridge 59 for a brand new Duncan Distortion
-Changed the pickup selector to a new one
-Changed the output jack
-Changed the volume pot for the bridge
-Changed the tone pot for the bridge
-Replaced old wires with brand new wires
-Raised and lowered bridge pickup
-Changed the cap for the bridge tone pot
-Used a multi-meter to check all pots and they seem normal
-Attached ground wire from bridge first to neck tone, then tried bridge tone

And of course I've checked the wiring vs. Seymour Duncan's diagrams about 100 times, and it's correct. I've never run into this problem before, and I'm kind of running out of ideas as far as troubleshooting.

Using the multimeter and touching the selector and output jack in various combinations...
Switched to bridge pickup:
-Neck to outer ring of jack 519k
-Neck to inner ring of jack 007k
-Bridge to outer ring of jack 0
-Bridge to inner ring of jack 512k

Switched to neck pickup:
-Neck to outer ring of jack 0
-Neck to inner ring of jack 007k
-Bridge to outer ring of jack 519k
-Bridge to inner ring of jack 512k


I knew I'd forget something, and it goes along with the readings. For the bridge pickup (old and new) when selected, it does this weird thing where turning down the tone will turn off the sound, but so does the normal action of turning down the volume pot.

I'm not sure what to make of the above readings. Do they even make sense the way I wrote it?

this part
shows short

EDIT
before ya'll ask:

.....of the volume pot
 
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Re: Help. Faint volume from one pickup

was going to say switch, but i'm wondering about your pots now (as well)

what are you soldering with..?
 
Re: Help. Faint volume from one pickup

Dumb question: When I bend the one terminal back, does it need to touch the pot or just the solder making the contact in between is good enough?

this part
shows short

EDIT
before ya'll ask:

.....of the volume pot

This diagram is the one I'm using.

http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=2h_2v_2t_3w

Red and White are taped together with electrical tape. Green and bare are twisted together and grounded on the volume pot. First terminal bent back and soldered to the back of the pot. Switch to middle terminal. Pickup's black wire to the third terminal. Third terminal to the first terminal of the tone pot. Etc.

was going to say switch, but i'm wondering about your pots now (as well)

what are you soldering with..?

Something I've been using for a few dozen pickup wiring jobs now. It says Electrical Solder Rosin Core SRC-20. 60% tin, 40% lead.
 
Re: Help. Faint volume from one pickup

Dumb question: When I bend the one terminal back, does it need to touch the pot or just the solder making the contact in between is good enough?
you can bend one terminal back and solder it to the back of the pot, or you can put a short length of wire between the back of the pot and the outer terminal in question, or you can connect one of the outer terminals to a different earth;
but the pickup needs to go onto 1 outer terminal and the other outer terminal needs to be earthed for the volume pot to work.
Something I've been using for a few dozen pickup wiring jobs now. It says Electrical Solder Rosin Core SRC-20. 60% tin, 40% lead.
what about your iron/tip?
 
Re: Help. Faint volume from one pickup

the red/white pair
put a touch of solder on those
before taping

a loose connection there will make the pickup not work
 
Re: Help. Faint volume from one pickup

the red/white pair
put a touch of solder on those
before taping

a loose connection there will make the pickup not work

This looks to be the answer! I untaped it and noticed the connection wasn't much of a connection between the two wires anymore. I've never solder these pairs before in any pickup, but I should probably make this regular practice instead of just twisting them. Thanks!
 
Re: Help. Faint volume from one pickup

This problem usually turns out to be some metal part of the selector switch making physical contact with the screening on the surface of the switch cavity (or the cavity cover plate), creating a short.

I know, I know, you posted that 6 and a half years ago. I'm not the original poster and he didn't clarify if he fixed the issue for sure. However, I bought a used Epi SG400 yesterday and had the same problem so got it for $50 with original hardshell case. After a few simple checks and moving cables, I removed the original pickup so no red/white wires there. I remembered your words so I removed the switch without disconnecting wires and it worked hanging out of the guitar. Wiped the cavity where switch touches inside front wood and reinstalled it. It continued to work just fine. No removing anything else had been needed. Nothing was unsoldered to fix the problem. Thank you, sir. People don't come back to give thanks.
 
Re: Help. Faint volume from one pickup

I have the same problem with a few of my import guitars (Korea and China). When I turn one of the volumes all the way down (off) I don't want any signal leaking through when the selector switch is in the middle position. I like to use the toggle as a kill switch like Randy Rhoads did. I did some experimentation and this is what works for me.
* It is not a bad component in the guitar (switch, ground, wire, capacitor, pot, jack etc.)
* It is how the pickup lead wire is connected to the pot (which lug)
Fix = de-solder each pickup lead wire from the middle (lug#2) of the volume pots and move it to lug #1. Move the 3-way switch wire from lug to the middle (lug#2).
If you want the volume to turn off when rotating the knob clockwise (left handed) solder the pickup lead wire to lug #3

So you just swap the pickup lead wire and the switch wire at the volume pots and that's it, nothing else.
 
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