Find Reviews and Compare Prices for:       All ProductsGuitar Effects     5.0 (1)   Add a review Seymour Duncan SFX-04 Twin Tube Mayhem Distortion Guitar Effects Pedal...   The Seymour Duncan SFX-04 Twin Tube Mayhem is a distortion pedal with a high-quality guitar preamp that includes a built-in boost. Using a duo of premium, mil-spec, subminiature, USA-made Phillips-Sylvania 62051 pentode tubes, the Seymour Duncan ... Have a question? Just Ask! Member Reviews Compare Prices Product Spec Send to a friend Category Overdrive, Distortion, Fuzz & Boost Bass Guitar EffectsCompression & SustainDelay & ReverbDesktop & Rack Guitar EffectsDIYEqualization & Tone ShapingFloor Guitar EffectsHarmonizer, Pitch Shifter, Octave Mod.Looper & SamplerModulation, Chorus, Flanging, PhasingMulti Effects PedalsNoise Gate & SuppressorOctave & Ring ModulatorOverdrive, Distortion, Fuzz & BoostPedalboardsPower SuppliesRouter, Signal Path & Pedal TunerVolume & ExpressionWah, Talk Box & Filter--------Suggest a new option Brand Seymour Duncan AguilarAMT ElectronicsAphexBarberBBEBehringerBlackstarBossCarl MartinCMATMODSCoffin CaseDamage ControlDanelectroDaphonDevi EverDigital MusicDigiTechDNA AnalogicDODDunlopEBSEbtechEffectsPowerSupplies.comElectro-HarmonixEMMAErnie BallEventideFenderFishmanFractal AudioFulltoneGatorGeorge DennisGig-FXGodlykeGoosoniqueworxGuitarPCB.comGuyatoneHaoIbanezISP TechnologiesJacquesJHS pedalsKeeleyKorgKrankLehleLine 6Mad ProfessorMahoneyMalekko Heavy IndustryMarshallMaxonMI EffectsModtone EffectsMorleyMorpheusMPMMusicians GearMXRPearlPedaltrainPigtronixPro CoRadialRed WitchRMCRocktronRoger Linn DesignRolandSabineSanyoSeymour DuncanSKBSnarling Dogs Sonic ResearchSR&DSuhrT-RexTC ElectronicTech 21THDToadWorksVisual SoundVoodoo LabVoxWamplerWhirlwindXotic EffectsZoomZVex--------Suggest a new option Something wrong in this page? Let us know! Related products: More Overdrive, Distortion, Fuzz & Boost Guitar Effects Other Guitar Effects internal use: spec24 spec275 spec584