In a typical tremolo equipped guitar we have a couple of springs that are stretched between the bridge and the body. When you hit the strings bridge and body resonate and cause the springs to resonate too. Pickups are not that far from the springs at all. In most guitars there’s no more than half an inch of wood between them and wood doesn’t do anything to prevent the pickups from picking up vibrations from the springs.

It’s very easy to test this, plug your guitar into the amp, turn the volume up, place the guitar on the bed or something with strings and pickup facing down. That will silence any string movements. Now tap the springs with screwdriver. If you can hear the tapping sound from the amp it means that pickups have…err picked up the vibration from the spring.

When playing this may add some reverby character to your guitar which gets even nastier when run through an overdriven amp or a pedal.

To get rid of it, we want to prevent the springs for vibrating, but keep them doing their main job – expanding and contracting without resistance. I found that the easiest way to do it is using isolation stripped from a typical UTP network cable most of us have in our homes. Cut the insulation in as many 1″-2″ pieces as you have springs and install them inside each of them. Try to repeat the test with tapping the springs and make sure that tremolo operates normally. If both test pass you’re ready to rock 🙂 Photo below shows installed “spring silencers” in my Ibanez RG2550.

Edit: I found that cable I used in one of my guitars had different insulation material which made squeaky sounds while springs are contracting/expanding. It’s probably safer to use some softer material to tame springs, like mouse pad foam or something similar.

Cheers,
Bane