Guitar Amplifier Microphones

What a microphone captures in front of a guitar cabinet

The recorded electric guitar sound comes from the complete chain: instrument, effects, amplifier, speaker and microphone position. Microphone selection therefore cannot be separated from the cabinet setup. Establish the intended clean or distorted character first, then find a useful pickup position. An unsuitable amplifier balance is not always repairable with equalisation after recording. Listen with bass, vocals and drums: a huge isolated tone may occupy too much space in the arrangement.

Prepare a riff, chords and single notes using normal performance dynamics. If several amplifier channels are used, test transitions between them. A position that suits a dense rhythm part may not be the best choice for a clean arpeggio. Decide whether the concert requires one practical compromise or studio sessions allow placement changes between separate parts. This also affects how convenient the mounting arrangement needs to be.

Speaker centre, cone edge and microphone angle

A position closer to the speaker centre generally produces a brighter character, while moving towards the edge can soften the top end. This is a useful direction for experimentation, not a guarantee across every cabinet. Move in small steps and compare short recordings at matched playback level. Test angle separately: rotating the capsule and moving it sideways are different changes and may affect the tone differently.

Check which side of the specific microphone receives sound. A flat body does not mean that every surface is the working side. Consult its instructions and orient it correctly towards the grille. When a cabinet contains several speakers, audition each at a comparable position; units within the same enclosure can sound different. Mark the chosen point in a way that does not damage the finish so that placement can be restored quickly after transport.

Distance, room sound and open back cabinets

A close position increases the proportion of direct sound and generally makes a loud stage easier to manage. Moving away introduces more room influence and changes the overall cabinet perspective. That can support a studio production, but reflections in an unsuitable room may complicate the recording. Establish one useful close channel before deciding whether a distant microphone has a worthwhile contribution. A spare input is not by itself a reason to add another source.

An open back amplifier also radiates rearward, so its position relative to a wall matters. If both front and rear are recorded, listen carefully to their combination: polarity and different distances influence the sum. Moving the cabinet itself can sometimes change the result more than replacing the microphone. Document cabinet location, microphone height and distance when parts will be doubled on another day or the session may need to be recreated later.

Amplifier distortion versus recording overload

Wanted guitar distortion and unwanted overload in the recording chain are different things. Set input level so that the strongest accents remain within preamplifier and converter capability. If clipping happens before the fader, turning the channel down does not remove it. Check microphone headroom, any available input pad and the complete signal path. Do not conclude that the capsule is faulty before examining the other stages.

A microphone connects to an appropriate microphone input, not to an amplifier's loudspeaker output. Speaker cables and microphone cables serve different purposes. Check the powering requirements for condenser or active models and follow the instructions for other designs. Choose amplifier volume according to tone and operating conditions rather than assuming that the maximum control setting always produces a better recording. Leave room in the recording level for the player's actual accents and changes in channel settings.

Adding a second microphone or a direct signal

A second microphone is useful when it contributes something specific, such as another attack character, density or room perspective. Listen to each separately, then together and in mono. If the combination becomes thin or harsh, adjust position or proportions before adding complex processing. A polarity switch can be part of the check but does not correct every timing difference. Preserve separate tracks so that the balance can be changed later without another performance.

A direct guitar signal can provide additional material for later processing, but needs a suitable instrument input or appropriate DI arrangement. It is not identical to the microphone signal in front of the speaker. A cabinet emulated output should also be evaluated as a distinct option. When blending different paths, assess timing and combined tone rather than only matching meter readings. Judge the result within the musical part and arrangement.

Practical questions about recording an amplifier

Is one microphone enough? Yes. One well positioned channel often gives a complete result and simplifies live setup. Can the microphone hang from its cable? Use only a placement method appropriate for the model and proper support; improvised hanging can change orientation or strain the connector. Why does the recording differ from the amplifier in the room? The microphone hears one point from one distance, while a person elsewhere hears a different relationship between speaker output and room sound.

When is a pad useful? When its use follows the instructions and prevents overload at the relevant stage. What should be checked before purchase? Cabinet type, available space, required tone, sound level, mixer input and supplied mounting accessories. How should models be compared? Record the same part at comparable positions, match playback loudness and listen in the mix. This is more informative than judging solely from a frequency response description or the appearance of the body.