Line 6 FM4 Filter Modeler
The Line 6 FM4 Filter Modeler is a filter modelling pedal developed and manufactured by U.S. guitar and bass equipment company, Line 6. It's recognised for its rectangular shape and its purple chasis. The FM4 comes from the same family of Line 6's Modeler Pedals which also include the Line 6 DL4 Delay Modeler, the Line 6 DM4 Distortion Modeler, the Line 6 AM4 Amp Modeler and the Line 6 MM4 Modulation Modeler. All of these pedals have been used by various artists.
The FM4 Filter Modeler is built to be used on both guitar and bass and includes a collection of both classic, vintage and collectible filter and monophonic synthesizer effects with the 24-bit processing. The FM4 includes an option to store four programmable presets and also includes 20 factory presets with 16 digital effects. The FM4 also has an option for an expression pedal, allowing the control of the filter cutoffs or the ability to morph between the settings with a foot. The control knobs are as follows; Effect Selector (browses through built-in effects), Freq (sets cutoff frequency), Q (sets the Q of the frequency), Speed (for modulation-based effects), Mode and Mix. It has stereo inputs and outputs.
The pedal was also available in a rack-mount version, called the "Line 6 Filter Pro". It features almost the exact effect settings as the stompbox version but also included features like the tap tempo function and tempo controls, additional XLR inputs and outputs and included 99 user definable programs. The rack-mount version featured studio modeler models based on the Mu-Tron III, Zvex Seek Wah, Oberheim VCF, the Voice Box, V-Tron, Electrix's Filter Factory, Spin Cycle, the Q Filter, Moog, Oberheim, Sequential Circuits & ARP Synthesizers and the Korg X911 Guitar Synth, amongst others.
Chris Wolstenholme uses the Line 6 FM4 Filter Modeler ever since the Origin of Symmetry era. It is most notably used on Sunburn when performed live, as Chris plays the growly synth sweeps during the verses. This is achieved on the pedal by putting it on the "Attack Synth" effect setting. Chris has kept it on the pedalboard ever since then, using it for Sunburn.
The two rack mount versions were used by Chris during the Absolution era, where the stompbox version wasn't included on the pedalboard itself. It was likely also used for Sunburn on the same setting, aswell as a couple of other uninentified songs.