A microphone polar pattern chart shows how sensitive a microphone is to sound arriving from different directions. Once you can read its angle labels, curves, and frequency markings, you can use it to place a mic deliberately, manage room sound, and reduce unwanted bleed.
What a polar pattern chart represents
A polar chart is a top-down view of a microphone’s directional response. Imagine the microphone at the center and a sound source moving around it at a fixed distance. The chart indicates how strongly the mic responds as that source moves from the front to the side or rear.
Most charts use a circular grid. The microphone’s front is usually at 0 degrees, located at the top. Moving clockwise or counterclockwise, 90 degrees is one side, 180 degrees is directly behind, and 270 degrees is the other side. The exact graphic may place the front elsewhere, so check its legend or the manufacturer’s diagram before applying the angles.
The curved lines show relative sensitivity. A curve that reaches the outer ring at the front and pulls inward behind the mic describes a microphone that is most sensitive in front and less sensitive at the rear. The inner rings usually mark reductions in level, often in decibels (dB). For example, a reading 6 dB below the outer reference means the response is quieter at that direction under the chart’s measurement conditions; it does not mean the mic completely rejects the sound.
A polar chart describes direction, not distance. It does not tell you how far away to place the microphone, how loud the recording will be, or whether the room sounds good. Those depend on the source, room, microphone, gain, and placement together.
Read the labels before choosing a curve
Before interpreting the shape, identify the chart’s orientation, scale, and frequency legend. These details prevent common mistakes, such as assuming the rear is always at the bottom or that every pattern is measured at the same frequency.
- Find the front reference. Look for 0 degrees, an arrow, a capsule icon, or a label such as “front.” The grille’s appearance alone may not reveal the microphone’s acoustic front; check the model’s instructions.
- Read the concentric scale. The rings may be labeled in dB, with the outer circle representing the on-axis reference and inner rings showing lower sensitivity. Some charts use different scales or omit ring labels, so avoid assigning an exact rejection value unless it is provided.
- Check the frequency key. Several curves on one chart commonly represent different frequencies. Each curve may have a color, line style, or frequency label. A chart with one curve may show only a selected frequency or a simplified summary.
- Look for the measurement note. Manufacturer charts may state the distance, test setup, or normalization method. Normalized curves compare directional response to the microphone’s front response at each frequency, while an absolute measurement may retain sensitivity differences between frequencies.
A chart is a guide to a microphone’s behavior, not a promise of identical performance in every studio. A nearby wall, desk, floor, or reflective instrument can alter what reaches the capsule, and off-axis tone may change as well as level.
Recognize common pickup shapes
The pattern name gives you a useful first clue, but the plotted curves show the detail. A microphone with a switchable pattern may have separate charts for each setting; each setting changes how it hears the room.
| Pattern | Typical chart shape | Useful starting point | Watch for |
|---|---|---|---|
| Omnidirectional | Nearly circular | Natural room sound or a source whose position may move | Picks up sound from the room and nearby surfaces |
| Cardioid | Rounded front lobe with a rear dip | One vocalist or source with unwanted sound behind the mic | Rear rejection is frequency-dependent and placement-sensitive |
| Supercardioid or hypercardioid | Narrower front lobe, with a smaller rear lobe | Isolating a source in a controlled setup | The rear lobe can pick up a monitor or another source |
| Figure-eight (bidirectional) | Similar front and rear lobes, deep side nulls | Two facing sources or a stereo technique | Both front and rear are active; the sides are the quieter directions |
An omni is not necessarily perfectly even at every frequency or angle. A cardioid is not a one-way sound gate. Supercardioid and hypercardioid patterns vary by design, so compare the actual curves rather than assuming one universal shape. A figure-eight mic hears both sides; placing the quieter sides toward competing sound can be more useful than pointing its front directly at the source.
Some microphones offer intermediate or selectable patterns, such as wide cardioid. If a particular recording requires a strong null or rear rejection, confirm that the chart belongs to the exact pattern setting you will use.
Compare frequency curves, not just the outline
Many charts plot multiple frequencies because directivity changes with frequency. Low-frequency sound may wrap around a microphone more readily than higher-frequency sound, while the mic’s capsule and acoustic design affect the details. As a result, the rear dip or side null shown by one curve may become shallower or shift at another frequency.
Use the legend to compare curves at the directions that matter for your setup. If the pattern is cardioid, inspect the rear at several frequencies rather than assuming one deep notch applies across the whole spectrum. If two singers are positioned at the sides of a figure-eight microphone, examine whether the side rejection remains useful across the frequencies that distinguish their voices or instruments.
A polar chart usually emphasizes level response. It may not fully communicate how off-axis sound is colored. A source that arrives from the side can be quieter but also sound darker, brighter, or otherwise different from a source directly in front. This matters when room reflections or bleed become prominent in a mix: lowering the level may not make the remaining sound blend naturally.
For practical decisions, consider the strongest unwanted sound and its important frequency content. A noisy keyboard, cymbal, or room reflection may not be controlled evenly by the same angle. When a chart does not provide enough frequency detail, treat its plotted shape as a starting point and judge the actual recording in context.
Apply the chart during a recording session
Start by identifying the wanted source and the main unwanted sound. Then choose a pattern and angle that favor the source while placing a quieter region of the chart toward the competing sound. This is a placement hypothesis to try, not a guarantee of isolation.
For a single vocal in a home room, cardioid is a common starting point. Aim the microphone’s front toward the singer, then consider placing a computer fan, reflective wall, or noisy part of the room toward the rear. If the chart shows a rear dip at the frequencies that matter, this can reduce some pickup. Keep in mind that reflections can arrive from other directions, and the rear dip may be less effective at certain frequencies.
For a guitar amplifier, first choose whether the mic should emphasize the speaker, the cabinet, or the room. A cardioid mic close to a speaker can help control room pickup, but moving the mic across the cone often changes tone more than changing a few degrees of angle. A figure-eight or omni may suit a roomier sound if the space is reasonably controlled. Use manufacturer guidance for safe placement around hot equipment and avoid obstructing ventilation.
For two people sharing one figure-eight mic, place each source toward one of the two active lobes and turn the side nulls toward the most troublesome room noise. Both people need to maintain their position and speaking or singing distance; the pattern itself will not compensate for large level differences. For stereo recording, use only a setup appropriate to the microphone pair, recorder inputs, and intended stereo format.
A simple setup routine:
- Confirm which pattern is selected and where the microphone’s front is.
- Mark the wanted source and the loudest competing sound around the mic.
- Compare their directions with the chart, including the relevant frequency curves.
- Position the mic and source, then record a short passage at the intended performance level.
- Listen for room sound, bleed, tonal changes, and level balance; adjust the angle or distance and record again.
If you change the pattern on a multi-pattern condenser, make sure the microphone and preamp are connected and operated according to their manuals. Use a suitable stand and shock mount when needed, and keep cables clear of moving performers and instrument hardware.
Use polar response in mixing and troubleshooting
A polar chart is most useful before recording, but it can explain why a track contains bleed or room sound. If the unwanted sound is strong despite aiming a cardioid mic’s rear toward it, check whether it reached the mic from a different route, such as a nearby wall reflection or a side angle. Repositioning the source or microphone may help more than relying on the nominal pattern.
When bleed is already recorded, try practical mix decisions in order: adjust track level and panning, use editing or automation where appropriate, and apply equalization or dynamics only if they improve the sound without damaging the wanted source. A directional pattern cannot remove sound that was captured, and aggressive processing may make both the source and bleed less natural. If isolation is essential, changing the recording setup is usually more effective than trying to fix severe bleed later.
Common problems have straightforward checks:
- The mic seems to reject the wrong side: verify the front orientation and pattern setting against the model documentation. Side-address microphones often require the singer to face a particular side of the body.
- A rear rejection notch does little: check the sound’s actual arrival direction and whether reflections are reaching the mic from other angles. Compare the frequency curves; rejection may vary across the spectrum.
- The recording sounds boxy or harsh off-axis: the mic may be receiving colored reflections. Change the angle, move away from a reflective surface, or try a different room position. A pattern chart alone cannot predict the room’s response.
- One performer is much louder in a shared setup: adjust their position, distance, or performance level. A polar pattern changes directional sensitivity, not the performers’ acoustic balance.
- The room sounds too dry or too roomy: try another pattern if available, but also change the mic-to-source distance and room position. Omni usually captures more room sound than cardioid in the same setup, though the result depends on reflections and placement.
Limits, compatibility, and safe use
A chart may represent a single microphone sample, a particular pattern mode, or measurements made under specified lab conditions. Real units and operating conditions can differ. The plotted response also cannot tell you how a particular vocalist, instrument, room, preamp, or monitoring arrangement will sound. Use the chart to narrow choices, then listen to a short recording made with your actual source and setup.
Confirm compatibility before relying on a pattern switch or microphone accessory. A passive ribbon, dynamic mic, and phantom-powered condenser have different connection and power requirements; follow the manufacturer’s instructions for the specific mic and preamp. Do not assume that a microphone can tolerate every power arrangement or that an accessory fits because it looks similar. Consult the product documentation for handling, mounting, cleaning, and storage, especially for delicate capsules or ribbons.
For home recording, the practical goal is not to find a curve that promises silence behind the mic. It is to understand where the mic is more and less sensitive, place the wanted source in a favorable direction, and account for the sound that still reaches the capsule. Keep the chart nearby when planning a session, but let the recorded result guide the final placement.