Shields up!

We’ve all experienced unwanted noise coming through our guitars.  Sometimes it’s 60 cycle hum (essentially noise caused by the electricity coming out of your wall), which single coil pickups particularly susceptible to; sometimes it’s electromagnetic interference – which is evidenced mostly by radio frequencies coming through your amp (why is it always the Spanish station?), but can also be interference from computer monitors, stage lighting, and other electronic equipment.  60 cycle hum can be mostly avoided by by using humbuckers, silent single coils, or setting your Strat or Tele in the middle positions (essentially creating a humbucking effect) – but how do you stop electromagnetic interference?

We’ve found the best way to help prevent stray noises from getting in to your guitar is to have it properly shielded.  Most guitars coming straight out of the factory only have a tiny bit of shielding – but if it’s not a full shield of the entire electronics cavity, it’s no real shield at all.  The function of a shield is essentially this: it creates a conductive cage around all your electronics, which intercepts incoming interference and then shunts it to ground.  It’s a simple trick, and can be very effective (especially for those of you living in and around the radio towers on Twin Peaks).

One of our favorite customers brought in his 1966 Fender Mustang for a complete overhaul, which included a shielding job.  We partnered with our friends at Guitar Mill to refinish the stripped body in bubble gum pink nitrocellulose lacquer (how wonderfully obnoxious!), and once we received the body back we started shielding the entire electronics cavity.  We covered the entire pickguard with conductive copper shielding tape (taking care to overlap each strip of tape and cutting it back from the pickguard edges, then wired up the original 1966 pickups:

The next step is to shield the electronic cavities.  It’s important that the shielding in the cavities are electrically connected to the shield on the pickguard – so we take a few strips of copper tape and put them over the pickguard screw holes, and fold them into the body routes.  When the pickguard is screwed in to the body, the copper shielding on the pickguard connects with the shielding in the body routes through the pickguard screws.  We do this BEFORE we apply shielding paint, to ensure conductivity throughout the shield.

Next we apply conductive shielding paint to the body routes:

When we install the electronics, the conductive paint and copper tape are connected to the ground, which effectively shunts any electronic interference out of the signal path.

While there’s no fool proof way to completely eliminate ALL noise, shielding can help out a LOT.  We are gigging artists ourselves, and we’ve found that a proper shielding job can really help keep those pesky radio stations, MIDI and DMX blips, and static out of our rigs even in the dingiest dive bars.  Got questions?  Give us a call or send us an email.

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