One of the simplest mods you can do to your guitar is to double the voltage running through your active pickup set. This is fancy talk for “add another battery”. It’s a simple modification to your guitar’s circuitry that anyone can perform. The amount of tonal difference you receive is quite significant – and if you don’t like it, it’s easily reversible.
Before you start:
Not every active pickup will accept an 18v modification.
The 18 volt modification is most commonly performed with EMG pickup sets – particularly the 81 85 set. In regard to Seymour Duncan’s active sets, there’s no change in the Blackouts’ tone when you wire in another battery, but according to their website, the mod will make a difference with their Livewire pickup sets.
The modification will not make your batteries drain faster, as the pickups are designed to draw on less than 100 microamps – which is very little. The circuit is also only on while your 1/4” cable is connected to the output jack – so always disconnect when you’re not playing. This will make sure you get a long life out of your batteries.
What differences will 18 volts make?
The first thing most people would assume is: 2x power = 2x output. But that’s simply not the way things work here since the purpose of the battery in the circuit isn’t to create a powerful magnetic flux, but to power a gain stage after the induction process and the introduction of a phased signal from a second reverse-coil to eliminate noise.
Even though active pickups were designed with high output in mind, they exist to address the impedance and noise issues that passive pickups create when they are overwound trying to achieve the same purpose. They also address the issue of a much darker tone that comes with the territory of overwinding.
The difference is strictly tonal.
“Powering your instrument with more than 9-Volts will not make it louder. You may notice some difference in the distortion quality of your guitar, or a different result from your amp. We encourage you to experiment.”
–EMG Pickups Manual
To keep things short, the most profound effect of increasing your power to 18v is an increased amount of headroom in the signal. I call it breathing room, since it suddenly feels like your notes have space to play in and stretch out. Don’t take my word for it though, take a listen for yourself in the video!
For more simple circuitry modifications, head over to the capacitor article, or the killswitch article (if you’re into that sort of thing)!
If you’re looking for more info on active pickups, the Duncan vs EMG article provides an extensive tonal analysis of the two most popular active pickup sets. Our custom pickup guide will tell you all you need to know about what makes a passive pickup sound great.