Hiss sound at loud volume/high gain with high-output pickups

[alexreinhold]

Hi all, I am really running out of ideas. Maybe you can help.

Guitar: Warmoth Tele with a metal pickguard and H-H Black Winter Set with custom nickel silver pickup covers, wired as per Seymour Duncan's instructions (3-way blade, 500k pots). Only difference: put in a battery powered LED light that is active when cable is plugged in (via a stereo input jack).

Problem: loud shrilling hiss when the guitar's volume knob is above 8/10 at high gain and at high volume.

What I've tried so far unsuccesfully:
- re-solder everything
- re-ground pickups to cover (solder)
- re-ground bridge
- wax-pot pickup covers
- wax-pot entire pickups
- disconnect battery
- re-shield/double-shield pickguard
- raise/lower pickups

Any other ideas of how I could solve this?

 

[Rick]

Are you using one of those power conditioners from voodoo labs. I had that and the conditioner got rid of it. Of course it cured the problem in my old house. Or does it happen every where you play? Have you experimented with other amps pedals locations? Gotta try to see if it's something outside of the guitar or house. Probably go to local guitar store. Bring the guitar and another guitar off the shelf. Find a nice amp and compare. Sometimes guitars just hiss or hum. Buzzzz. This kind of issue can make you crazy.

 

[alexreinhold]

Hey Rick - the problem exists everywhere (home, rehearsal room, live venues) and only with this guitar. I even have another guitar with the exact same pickups. No problem :-/

 

[Rick]

Then I'd give up and bring it to my tech who has the tools that can tell which component is glitchy. You are now at the boundry of my knowledge.

 

[Tretgeraet]

Does that happen any pickup position?

Does it happen wenn the pickup isn't mounted but just... let's say, hanging out of the cavity?

Did you try to disconnect the LED?

You already narrowed the problem to the guitar, now you need to narrow it down further.

 

[alexreinhold]

Does that happen any pickup position?

Does it happen wenn the pickup isn't mounted but just... let's say, hanging out of the cavity?

Did you try to disconnect the LED?

You already narrowed the problem to the guitar, now you need to narrow it down further.

- yes, any pickup position
- yes, also when hanging
- only disconnected the battery, not the LED yet.

This is what Claude says:
Pickup/Wiring Issues:

• Test with pickups completely disconnected - if hiss remains, it's in the electronics
• Verify pickup lead shielding isn't damaged where it enters the covers

Potentiometer/Component Issues:

• Replace the volume pot - 500k carbon composition pots can get noisy, especially cheaper ones
• Try a different pot taper (audio vs linear) or switch to metal film resistor pots
• Check for cold solder joints specifically on pot casings to ground
• Install treble bleed circuit - sometimes helps with high-frequency noise at higher settings

Jack/Connection Issues:

• The stereo jack modification could be creating ground loops or noise - try temporarily wiring a standard mono jack to test
• Check if the LED circuit is creating interference - disconnect the LED entirely (not just battery)
• Ensure proper star grounding scheme

 

[supertruper1988]

Because its all pickup positions, I think its in the wiring. I would be looking at jack connections and if the jack touches the body when you plug in a cable. then look at pots and new capacitors. I would also consider putting the LED on its own circuit that is turned on with a micro switch in the back cover to eliminate the chance that its causing the issue.

 

[Tretgeraet]

- yes, any pickup position
- yes, also when hanging
- only disconnected the battery, not the LED yet.

This is what Claude says:
Pickup/Wiring Issues:

• Test with pickups completely disconnected - if hiss remains, it's in the electronics
• Verify pickup lead shielding isn't damaged where it enters the covers

Potentiometer/Component Issues:

• Replace the volume pot - 500k carbon composition pots can get noisy, especially cheaper ones
• Try a different pot taper (audio vs linear) or switch to metal film resistor pots
• Check for cold solder joints specifically on pot casings to ground
• Install treble bleed circuit - sometimes helps with high-frequency noise at higher settings

Jack/Connection Issues:

• The stereo jack modification could be creating ground loops or noise - try temporarily wiring a standard mono jack to test
• Check if the LED circuit is creating interference - disconnect the LED entirely (not just battery)
• Ensure proper star grounding scheme

A lot of good points there!

Those "custom nickel silver pickup covers", were they factory installed?

If yes, then in addition to

- yes, any pickup position
- yes, also when hanging

you cross the pickups out.

I would
- disconnect the LED
- temporarily switch to a mono jack
- replace the pot

In that order.

 

[alexreinhold]

thanks supertruper and Tretgerät. I will try and keep you posted. It's been driving me absolutely nuts

 

[Spud]

Lift the ground from the led.

 

[NedRyerson]

The LED is the main culprit in my mind.