Amp Settings Explained: Gain, Bass, Mid, Treble & More

Drive into an amp that is already working

Tube Screamer into a saturated amp

1980s onward — The most copied trick in metal, and it is a filter trick rather than a gain trick.

• Chain: guitar → noise gate → TS with drive at zero and level high → high-gain amp input → 4x12
• Mechanisms: Pre-clipping high-pass, Soft clipping, High input impedance drive, Frequency-selective clipping, Post-clipping low-pass
• Gear: TS808, TS9, Maxon OD808, Boss SD-1 into a 5150, Rectifier or JCM800
• Appears in: pairings 07, 22
• Correction: With drive at zero the pedal is barely distorting at all. What it is doing is stripping everything below 720 Hz before the amp's preamp ever sees it, so palm mutes stop turning to mud. The tightening is the high-pass, not the diodes.

Pedal into amp stage (6)

18. THE PREAMP IS ALREADY THE DRIVE

Overdrive → Effects loop — The four cable method rig, The rack rig and buffered loop switching

• Mechanisms: Effects loop, Preamp vs power amp distortion, Four cable method, Time before drive, Tone stack placement
• The move: A drive pedal placed in the amplifier's loop rather than at the front, which is where it does not belong and occasionally exactly where it should be.
• The friction: The loop sits after the preamp distortion, so a drive there is clipping an already-clipped signal at line level rather than shaping what gets clipped. Usually that is mud. But on a clean amp the loop's higher level and different impedance can make the same pedal sound tighter and louder than it does out front.
• The recipe: Front of the amp for anything meant to interact with the preamp; the loop for level boosts and for EQ you want applied after the distortion. If a pedal sounds thin in the loop, it is a level mismatch — many loops run at line level and pedals expect instrument level.

Loud, tight, high-gain guitar where the boost is clearly happening after the distortion rather than before it, four and a half minutes, 140 BPM, controlled and enormous. The amplifier's preamp supplies all the saturation, and a level boost sits after it in the amplifier's own loop, so the character of the distortion is completely unchanged between rhythm and lead — only the volume and the presence in the mix jump. That is audibly different from a boost in front, which would have changed the texture as well. The tone is dense and midrange-forward with a hard attack, into a real cabinet that band-limits everything above 5 kHz. Rhythm sections are palm-muted and precise; lead sections are the same tone, several decibels louder, sitting on top of the band. Delay and reverb also sit in that loop, so their repeats stay clear and undistorted behind the saturated tone rather than being re-clipped into mush. Bass and drums are tight and modern. The arrangement alternates between rhythm and lead several times so the level jump is obvious each time. It ends on a sustained lead note held into feedback.

19. DRIVING THE SPRINGS

Spring reverb unit → Front of the amp — The surf rig, The blackface clean rig

• Mechanisms: Spring reverb, Dwell, Tank decay rating, Bias tremolo, Band-limiting
• The move: An outboard tube reverb tank placed between guitar and amplifier rather than in a loop, so the springs themselves are being overdriven.
• The friction: Everything about modern practice says reverb goes last. This puts it first, and it works because the tank is a physical device with its own gain stage: the Dwell control is a drive level feeding the input transducer, not a decay time, so turning it up makes the springs distort rather than making the reverb longer.
• The recipe: Dwell high, mix around a third, tone bright, into a clean amp with headroom. Do not expect a loop or a digital spring emulation to do this — the crash comes from mechanically overdriving a real tank, and there is nothing in the algorithm to overdrive. Keep the amp clean or the tank's output will clip it as well.

Bright, wet, dripping instrumental surf guitar with an enormous crashing reverb, three minutes, 168 BPM, urgent and splashy. The reverb is a real mechanical spring tank being driven hard from a valve gain stage placed before the amplifier, so it is not a subtle ambience but a huge, splashing, metallic wash that crashes and overloads on every hard attack — the springs themselves are distorting. Because a helical spring is a dispersive medium, different frequencies arrive at different times and every transient smears out into that unmistakable drip. The guitar is a bright single-coil instrument with heavy flatwound strings, played with fast tremolo picking on the bridge pickup and long glissando slides down the low strings. The amplifier is clean and loud with plenty of headroom, and its own valve tremolo pulses underneath at a fast rate, thick and gooey because it works by modulating the power tubes' bias. Drums are simple, hard-hit and reverberant. Bass is a simple driving eighth-note line. No distortion anywhere. It ends on a crashing low-string slide left to ring out through the reverb tank.

20. AFTER THE TONE STACK

Modulation → Power amp — The rack rig and buffered loop switching, The stereo ambient rig

• Mechanisms: Tone stack placement, Passive FMV tone stack, Effects loop, Stages to notches, Chorus
• The move: Modulation placed downstream of the preamp and its EQ, so nothing shapes it afterwards.
• The friction: In a normal amplifier the tone stack sits early — Fender after a cathode follower following the first stage, Marshall after the second stage and plate-driven — so anything in front of it gets EQ'd. Put modulation after and it arrives at the power tubes unfiltered, deeper and more obvious, with none of the amp's voicing applied.
• The recipe: Loop or power-amp input for depth and clarity; front of the amp for a modulation that sits inside the tone. If a phaser is too subtle in front of a high-gain amp, moving it to the loop is more effective than turning up the depth — and if it is now too much, that is the amp's tone stack no longer taming it.

Clean guitar with a very deep, unmistakable modulation that sits on top of the tone rather than inside it, five minutes, 88 BPM, liquid and hypnotic. The modulation is placed after all of the amplifier's own equalisation, so it arrives at the power stage unfiltered: the sweep is wide, the notches are deep, and the effect is obviously an effect rather than a colouration. It moves slowly, taking many bars to complete a cycle, and because it is downstream of the tone controls, turning the amp's treble or bass does nothing to tame it. The underlying guitar tone is clean and full with a lot of low-mid weight, played fingerstyle with the thumb on the low strings and fingers above, arpeggiating a cycle that repeats without resolving. Long notes are allowed to ring into one another. The amplifier is loud but clean, into an open-backed cabinet so the sound is wide and omnidirectional in the room. Bass is sustained and simple; drums are brushed and quiet. There is no distortion. The modulation continues after the playing stops, and the piece ends on a chord left to fade through several full sweeps.

21. DETECT ON ONE SIGNAL, MUTE ON ANOTHER

Noise gate → High-gain preamp — The djent direct rig, The scooped Mesa rig

• Mechanisms: Two-gate detection, Input gate, Attack time, Pre-clipping high-pass, Impulse response
• The move: A gate arranged so that what it listens to and what it cuts are two different points in the chain.
• The friction: A gate at the input is nearly useless, because the hiss is generated downstream of it. A gate after the gain block can act on the real noise, but distortion has put a sustaining note and the noise floor at nearly the same level, so it chatters. Neither position works alone.
• The recipe: One gate keying off the clean guitar signal for detection, a second after the gain block doing the muting — which is what a four-cable gate or a modern gate with a key input is for. Set the threshold from the clean signal, not from the distorted one. Fast attack, short hold, and let the release be the only thing you tune by ear.

Extremely tight, percussive, rhythmically precise heavy guitar where the silences are as important as the notes, five minutes, 108 BPM, mechanical and hypnotic. Two heavily distorted extended-range guitars are clamped under a hard noise gate with almost instant attack and very short hold, so every palm-muted note is a short discrete event with no ring and no decay, and the gaps between them are absolutely silent — no hiss, no hum, no bleed. That silence is the rhythmic figure: the pattern is defined as much by where nothing happens as by where the notes fall. The gate keys off the clean signal rather than the distorted one, so it never chatters on sustained notes and never clips the front of a chug. The tone is a hard dry click around 2 to 4 kHz over a compressed midrange grind, high-passed so the lowest fundamental is removed. The riff is seven beats long against drums holding a completely steady four-four, so it lands somewhere different on every repetition. Bass doubles the guitars exactly. It ends with everything cutting together into a full bar of silence.

22. CHOOSE WHAT DISTORTS OR RESHAPE IT

EQ → Distortion — The scooped Mesa rig, Tube Screamer into a saturated amp

• Mechanisms: Frequency-selective clipping, Baxandall stack, Passive FMV tone stack, Pre-clipping high-pass, Effects loop
• The move: The same equaliser in two positions doing two completely different jobs.
• The friction: Before the clipper, an EQ decides which frequencies distort most — boost a band and that band saturates hardest. After the clipper, it can only reshape harmonics that already exist. Same box, same settings, entirely different function, and no amount of listening to it in one position tells you what it does in the other.
• The recipe: Before the drive for tightening and for choosing the character of the saturation — a high-pass here is worth more than any tone knob. After the drive, or in the amp's loop, for removing fizz and for fitting the guitar into a mix. The Mesa graphic sits after the preamp for exactly this reason, which is why its scoop stays articulate.

Aggressive scooped rhythm guitar where the midrange has clearly been removed after the distortion rather than before it, four minutes, 200 BPM, fast and cutting. The amplifier's cascading preamp supplies all the gain, and a graphic equaliser set in a deep V curve sits after that preamp, so the scoop is applied to distortion that has already happened — the result stays articulate and defined rather than going hollow and mushy the way a pre-distortion scoop would. Fast downpicked single-note figures on the low strings stay completely separate, each note a distinct percussive event. The tone is bright and sharp at the top, deep and tight at the bottom, with a pronounced hole in the middle. Two guitars are tracked hard left and right playing identically. Drums are extremely fast with a thin snare and a clicking kick. Bass fills the midrange gap the guitars have vacated and is unusually prominent as a result. Playing is relentless, with sudden unison stops. The cabinet is a real four-by-twelve so there is no fizz above 5 kHz. It ends on a fast unison figure cut dead.

23. ONE ZERO CROSSING PER CYCLE

Octave pedal → High-gain rig — The doom and sludge rig, Fuzz into a cranked amp

• Mechanisms: Monophonic tracking limit, Octave down by division, Octave up by rectification, Downtuning tension loss, Inharmonicity
• The move: An analogue octave circuit asked to track a downtuned, harmonically dense signal.
• The friction: Both analogue octave types need one unambiguous repeating feature per cycle — a zero crossing for the divider, the waveform shape for the rectifier. Low strings and chords produce dense waveforms with multiple crossings per true cycle and a fundamental that is often weaker than the second harmonic, so the detector has nothing to lock onto. It is a limit of monophonic tracking, not a fault in any one pedal.
• The recipe: Octave first in the chain, before any distortion, and fed the cleanest possible signal — neck pickup, tone rolled back, single notes only, above the fifth fret. If you need it on chords or low strings, use a digital pitch shifter with proper pitch detection and accept the latency. Or use the glitching deliberately.

Heavy guitar with a synthetic sub-octave under the riff that periodically breaks down into glitching, five minutes, 92 BPM, unstable and menacing. An analogue octave-down circuit tracks the guitar by squaring the waveform and halving its frequency, so on clean single notes high on the neck it produces a solid, square, synthetic note an octave below — and on low notes and anything approaching a chord it loses the fundamental entirely and stutters, jumping between octaves and dropping out. That instability is used deliberately: the riff climbs into the region where tracking is solid and then descends into the region where it falls apart, so the sub-octave shreds and glitches on the low notes. Behind it a heavily distorted guitar plays the same figure, and the amplifier is loud into multiple cabinets so the low end is physical. A screaming octave-up fuzz appears in the second half on single notes near the twelfth fret, clean and vocal there, turning into clangy inharmonic chaos the moment two notes sound together. Drums are slow and enormous. It ends with the octave circuit oscillating on its own after the guitar stops.

Amp into load (6)

24. THE ELECTRICAL HALF OF LOUD

Cranked amp → Attenuator — The Echoplex-front rig, Plexi at full volume, no pedals

• Mechanisms: Attenuator limits, Reactive vs resistive load, Thermal power compression, Mechanical non-linearity, Power supply sag, Power scaling
• The move: A full-output amplifier into a load that dissipates most of its power as heat.
• The friction: It preserves the output stage's behaviour and none of the speaker's. A cabinet at volume contributes excursion-dependent cone breakup and thermal power compression — a voice coil going from 20 °C to 200 °C loses 4.7 dB of sensitivity — and an attenuator cannot reproduce any of that, because the cone is no longer moving that much air.
• The recipe: Use a reactive attenuator, not a resistive one: a flat resistive load makes the tone more compressed and dark as attenuation rises, and records far too bright and buzzy. Expect to add treble back as you attenuate further. And accept the limit — heavy attenuation of a Plexi will never sound like a loud Plexi, because half the mechanism has been removed.

Overdriven valve amplifier tone at moderate volume, with all the electrical compression of a cranked amp and none of the cabinet's own breakup, four minutes, 96 BPM, thick and slightly flat. The power stage is genuinely at full output — the tubes are working, the supply is sagging on hard attacks and swelling back behind them, and the transformer is contributing its own soft saturation on low notes. But the speaker is barely moving, so the ragged excursion-dependent cone cry and the thermal compression that a loud cabinet would add are simply absent: the tone is smooth, even and controlled where a loud amp would be unruly. It sounds like a photograph of loudness rather than loudness. The top end needs help and is bright as a result. Playing is blues-rock lead and rhythm, dynamic and dependent on pick attack, with the guitar's volume control used constantly. Drums and bass are recorded at natural volume in the same room, so the guitar's restraint is obvious against them. It ends on a sustained chord that decays without ever blooming into feedback, because there is not enough acoustic energy in the room to start one.

25. THE FROZEN CABINET

Cranked amp → Reactive load and IR — The silent rig, The djent direct rig, The profiler and modeller rig

• Mechanisms: Impulse response, Reactive vs resistive load, Mic placement, Impedance curve, Attenuator limits
• The move: A full amplifier into a speaker-like electrical load, with the cabinet replaced by a linear filter.
• The friction: An impulse response is a linear time-invariant capture. It holds frequency response, phase, inter-speaker cancellation and the entire mic and converter chain — and it categorically cannot hold distortion, dynamic compression or cone breakup. So the amp responds correctly and the cabinet does not respond at all.
• The recipe: The load must be reactive so the output stage sees a speaker-like impedance curve; a resistive one changes what the amp does. Then pick the IR by the mic position you would actually have used — moving an SM57 from dust cap to cone edge is worth 8 dB at 1.6 kHz, which is a bigger move than most EQ. Blend two IRs rather than EQ-ing one.

Silent-recorded valve amplifier tone, perfectly repeatable and completely consistent from take to take, five minutes, 124 BPM, precise and modern. The amplifier is real and running at full output into a reactive load that presents a speaker-like impedance curve, so the output stage behaves exactly as it would into a cabinet — sagging, compressing and saturating naturally. The cabinet itself is a fixed linear capture: it applies the frequency and phase response of a specific speaker, cabinet, microphone and preamp, and it never changes. That means hard playing gets louder and more distorted at the amplifier but never adds the ragged cone breakup a real speaker would contribute, so the top end stays smooth and identical at every dynamic level. The tone is tight, focused and slightly two-dimensional, sitting perfectly in a dense mix. Two guitars are tracked left and right with different cabinet captures — one brighter and centred on the dust cap, one darker and further out toward the cone edge — and the difference between them creates the width. Bass and drums are programmed and tight. It ends on a stereo chord with the two captures decaying at slightly different rates.

26. DOUBLE OR HALF

Amp head → Mismatched impedance — The doom and sludge rig, Plexi at full volume, no pedals

• Mechanisms: Impedance mismatch, Impedance curve, Amp output impedance, Output transformer, Negative feedback
• The move: A valve output stage driving a load that is not what its transformer tap says.
• The friction: The load is a curve, not a number: a measured 8 Ω driver reads exactly 8 Ω at three frequencies, peaks near 70 Ω just above 100 Hz and climbs to around 50 Ω by 20 kHz. Against that, a nominal mismatch is a smaller change than it sounds — until it is not, and then it is a repair rather than a tone.
• The recipe: The convention that keeps appearing: mismatches within double or half the rated impedance are generally considered safe. Beyond that, too high a load stresses the transformer and tubes with excess voltage and too low pulls excess current. Solid-state amps are the opposite — too low a load is the dangerous direction and there is no transformer to protect.

Loud valve guitar tone with a slightly loose, unusual feel, four and a half minutes, 84 BPM, woolly and characterful. The output stage is driving a load that does not quite match its rating, so the damping factor is off and the amplifier's grip on the cone is looser than it should be: low notes bloom and overhang slightly, the low midrange is fatter, and the whole thing feels a fraction slower to respond than a matched rig. The amplifier is a valve head at high volume, sagging under hard attacks, and the speaker's own impedance peak just above 100 Hz is exaggerated by the high source impedance, giving a pronounced resonant thump on every low note. Playing is slow and heavy: sustained power chords with lots of space between them, allowed to bloom and decay fully. The cabinet is closed-back with real cone breakup around 2 to 3 kHz and nothing above 5 kHz. Drums are slow, enormous and slightly behind the beat. Bass is deep and simple. There are no effects at all beyond the room. It ends on a low chord left to feed back and slowly rise in pitch.

27. THE BACK PANEL IS A FILTER

Amp head → Open-back or closed-back cab — The blackface clean rig, Plexi at full volume, no pedals

• Mechanisms: Open back vs closed back, Multiple drivers, Band-limiting, Sensitivity, Mechanical non-linearity
• The move: The same head into two cabinets that differ only in whether the rear is sealed.
• The friction: Front and rear waves interfere below the dipole peak, rolling off at about 6 dB per octave, and sealing the back raises the driver's resonance by roughly two and a half semitones. So the choice is not a preference between two flavours, it is a genuine change in low-frequency response and in how directional the rig is in the room.
• The recipe: Open back for clean and mid-forward tones and for filling a small room; closed back for tight low end, projection and anything downtuned. If a rig sounds huge on stage and thin out front, that is an open back radiating backwards. And note that the cabinet choice interacts with everything upstream — a scooped preamp into an open back has almost nothing left in the middle.

The same guitar part played twice through two cabinets, five minutes, 100 BPM, illustrative and warm. First half: an open-backed combo, where the front and rear waves partially cancel below the dipole peak so the deep low end is missing, but the low midrange is generous and punchy and the sound spreads omnidirectionally around the room rather than beaming forward. It is airy at the top and feels close and enveloping. Second half: the identical amplifier into a sealed cabinet, where the driver's resonance sits higher and nothing radiates backwards — the low end is tighter, deeper and far more directional, the tone is more focused and forward, and the airiness is gone. The guitar is mid-gain throughout, played with dynamic chord work and single-note lines so the difference in low-frequency behaviour is obvious on both. The amplifier settings never change between halves. Recording is one microphone at a fixed distance, so the cabinet is the only variable. Bass and drums are steady and unremarkable by design. It ends with both cabinets running together on a final chord.

28. TWO SPEAKERS, ONE PHASE PROBLEM

One head → Two different cabs — The two-amp grunge rig, The rack rig and buffered loop switching

• Mechanisms: Multiple drivers, Mic placement, Impulse response, Published speaker specs, Sensitivity
• The move: A single amplifier driving two dissimilar cabinets at once, which is a recording trick and a live problem.
• The friction: Two drivers with different resonances and different distances to a microphone will partially cancel each other. That is exactly what an impulse response captures as inter-speaker cancellation — and it can be a gorgeous comb-filtered thickening or a hole in the midrange, depending entirely on placement, with nothing on the amplifier able to fix it.
• The recipe: Mic each cabinet separately and check the sum in mono before committing; if the low end disappears, flip the polarity on one and check again. Keep the microphone distances equal or deliberately unequal, not accidentally so. Live, two dissimilar cabinets in one room is a lottery — the audience hears a different sum at every seat.

Enormous layered guitar tone built from two different speaker cabinets running from one amplifier, five minutes, 112 BPM, wide and complex. The head drives a closed-back cabinet with a modern high-sensitivity driver and an open-backed cabinet with a low-powered vintage-voiced one at the same time, and each is captured with its own microphone. Because the two drivers have different resonances and their microphones sit at slightly different distances, the sum has a distinct comb-filtered character — certain narrow bands reinforced, others partially cancelled — that gives the tone a hollow, three-dimensional quality no single cabinet produces. The vintage driver breaks up early and adds ragged cone distortion on top of the amplifier's own; the modern one stays composed and supplies the low end and the top. Together they read as one very large, slightly unstable guitar sound. Playing is mid-gain riff-based rock with a heavy pick attack and open ringing strings. Drums are live and roomy; bass is thick. The two cabinet signals are panned slightly apart rather than hard, so the width is subtle. It ends on a chord where the two cabinets decay at visibly different rates.

29. DOPPLER YOU CANNOT SIMULATE

Amp → Rotating baffle — The Texas blues rig, The jangle rig

• Mechanisms: Rotating baffle, Chorus, Stages to notches, Vibrato, Uni-Vibe stagger
• The move: A real speaker mechanically moved, rather than a circuit imitating the result.
• The friction: A rotating baffle Doppler-shifts an actual sound source, so pitch, amplitude and radiation pattern all change together and the room becomes part of the effect. A phaser produces notches, a chorus produces detuning, and neither produces the physical three-dimensional movement — which is why every phase-shift approximation is recognisable as one.
• The recipe: Mic it in stereo, at least two microphones at different angles, and let the room in — a close mono mic throws away most of what makes it work. Speed changes are the effect, so use the ramp between slow and fast rather than parking it. And expect the recorded version to be far more convincing than the in-room version to anyone not standing in front of it.

Clean and lightly overdriven guitar through a physically rotating speaker baffle, five minutes, 76 BPM, three-dimensional and unmistakably mechanical. The sound source itself is moving, so every note is Doppler-shifted in pitch as well as swept in amplitude, and the room's reflections move with it — the effect surrounds the listener rather than sitting in the stereo field. Two microphones at different angles capture it, giving genuine width that is not a delay or a phase trick. The rotation speed changes during the piece, ramping slowly from a lazy sway up to a fast shimmer and back down, and the ramp itself is the most expressive gesture in the arrangement. The guitar underneath is warm and mid-focused, played with sustained chords and slow melodic lines so there is time for the rotation to work on each note. The amplifier is only just breaking up. A small amount of natural room reverb, nothing electronic. Bass is simple and warm; drums are brushed and quiet. It ends with the rotation slowing to a stop over a final held chord, the pitch wobble getting slower and wider until it settles.