Controlled Feedback Techniques for Guitar

Controlled feedback transforms potentially problematic amplifier-guitar interaction into a musical tool. Rather than fighting feedback, skilled guitarists harness it for sustain and harmonic effects. Understanding controlled feedback techniques enables using this phenomenon musically.

Feedback Fundamentals

Sound from speakers causes guitar strings to vibrate sympathetically. The vibration feeds through pickups back to the amplifier. The loop creates sustained tone.

Different harmonics feedback at different positions. The fundamental, octave, fifth, and other intervals each have sweet spots. Position determines which harmonic dominates.

Volume threshold must be met for feedback to sustain. Below a certain level, the loop doesn’t maintain itself. Sufficient volume is required.

Position and Angle

Standing directly in front of the speaker favors fundamental feedback. The direct sound pressure drives the strings most efficiently. This position produces the strongest fundamental.

Angled positions favor overtones. Moving to the side changes which harmonics receive reinforcement. The angle selects different pitches.

Distance affects feedback ease. Closer positions feedback more readily. Greater distances require more volume.

Height relative to speakers matters. Different heights favor different frequencies. Experimentation reveals optimal positions for desired effects.

Selecting Harmonics

Fret position affects available harmonics. The natural harmonic nodes along the string determine what feeds back. Fretting at specific points encourages specific overtones.

Light touch at harmonic nodes encourages overtone feedback. Touching the string lightly at the twelfth, seventh, or fifth fret favors those harmonics. The technique selects pitches.

Moving the guitar in space shifts feedback pitch. The gradual position change transitions between harmonics. The movement becomes part of the performance.

Practical Techniques

Starting a note and allowing feedback to develop creates musical effect. The transition from picked note to sustained feedback has character. The evolution serves melodic purposes.

Vibrato during feedback adds expression. The pitch variation while sustaining creates interest. The technique remains expressive during feedback.

Whammy bar manipulation shapes feedback pitch. The bar allows controlled pitch movement. The effect ranges from subtle vibrato to dramatic swoops.

Moving pickup selector during feedback changes character. Different pickups feedback differently. Switching during sustained feedback creates tonal shift.

Volume and Gain Settings

Higher gain settings lower feedback threshold. The additional amplification makes feedback easier. High-gain situations require less volume for feedback.

Power tube saturation encourages feedback. The compression helps maintain the loop. Cranked tube amps feedback naturally.

Clean settings require more volume for feedback. Without compression, the loop is harder to maintain. Very loud clean settings may be needed.

Managing Unwanted Feedback

Noise gates can control feedback when not desired. The gate cuts the signal when below threshold. Between intended feedback, the gate eliminates unwanted sustain.

Position awareness prevents accidental feedback. Knowing where feedback sweet spots are helps avoid them. Moving away stops unwanted feedback.

Lower volume obviously reduces feedback. When feedback isn’t desired, reducing level addresses it. The simple solution works.

Recording Controlled Feedback

The musical use of feedback records effectively. Capturing the intentional sustain preserves the performance element. The technique adds to recordings.

Consistency between takes may be challenging. Feedback is somewhat unpredictable. Multiple takes provide options.

Monitoring positioning helps repeatability. Marks on the floor or other references aid consistent positioning. The repeatability improves with preparation.

Electronic Alternatives

Sustainer pickups provide feedback-like effects without volume. The electromagnetic sustain maintains vibration. Any volume level works.

EBow creates sustained vibration through electromagnetic drive. The handheld device vibrates individual strings. The effect resembles feedback.

Infinite sustain pedals process signal to simulate feedback. The electronic approach works at any volume. The results approximate the effect.

Compressors before high gain encourage easier feedback. The sustained signal level helps maintain the loop. The processing lowers threshold.

Genre Applications

Rock solos extensively use controlled feedback. The sustained notes singing through songs define the technique’s use. Classic rock especially features feedback.

Blues bends into feedback work beautifully. The emotional sustain suits blues expression. The technique serves the genre’s feeling.

Experimental music uses feedback as primary material. Beyond sustain effects, feedback becomes compositional element. The approach differs from supportive use.

Combining with Effects

Delay extends feedback into spatial territory. The sustained tone through delay creates ambient effects. The combination expands possibilities.

Reverb adds dimension to feedback tones. The sustained notes in reverberant space create atmosphere. The processing enhances the effect.

Modulation during feedback creates movement. Chorus or flanger on sustained feedback adds interest. The combination produces evolving tones.

Practice and Development

Developing feedback control takes time. The technique involves physical positioning, not just equipment. Practice builds intuition.

Experimentation reveals possibilities. Each guitar, amplifier, and room combination behaves differently. Exploration discovers what’s available.

Integration into playing requires musicality. Feedback should serve the music. The technique becomes another expressive tool.