Shure SM81 Review: Capturing the Essence of Acoustic Guitars Onstage and in the Studio

When it comes to recording and amplifying acoustic guitars, capturing the true essence of their rich tonal characteristics is essential. I cannot remember the first time I used the SM81. It has become a staple in any recording arsenal of acoustic guitars. That’s why it’s included in my article 7 Proven Winners: Discovering the Best Mic for Acoustic Guitar. The Shure SM81 has long been a go-to microphone choice for both studio engineers and live sound professionals seeking a reliable and versatile solution. In this review, I’ll explore the capabilities of the Shure SM81 and its performance when used for recording studio and live acoustic guitars.

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Design and Build Quality

The Shure SM81 is renowned for its robust design and exceptional build quality, making it a reliable choice for professional recording and live sound applications. I can attest to both and the following details are what make it a great design and build.

Construction

The SM81 features sturdy and durable metal construction, ensuring longevity and resilience to withstand the demands of both studio and live environments. The microphone’s body withstands the rigors of regular use and transportation.

Compact Size

With its compact size, the SM81 is easy to handle and position. It measures approximately 20 cm (7.9 inches) in length and has a diameter of about 2.5 cm (1 inch). Its compact form factor allows for flexible placement, making it suitable for various recording and performance scenarios.

Cardioid Polar Pattern

The SM81 utilizes a cardioid polar pattern, which means it captures sound primarily from the front and rejects sound from the sides and rear. This pattern helps to isolate the intended sound source, reducing unwanted background noise and ambient sound interference.

Integrated Pop Filter

The microphone includes an integrated pop filter that helps reduce plosive sounds caused by strong bursts of air hitting the microphone capsule. This feature is particularly useful when recording vocals or close-miking instruments to achieve cleaner and more intelligible recordings.

Switchable Low-Frequency Roll-Off

The SM81 offers a switchable low-frequency roll-off feature that allows you to reduce or eliminate low-frequency rumble or handling noise. This switch, located on the microphone body, provides added versatility and control over the captured sound.

XLR Connector

The SM81 features a standard XLR connector, which ensures a secure and reliable connection to compatible audio interfaces, mixers, or preamps. This connector type is widely used in professional audio setups, providing compatibility and ease of integration into existing setups.

Overall, the Shure SM81’s design and build quality aim to provide durability, ease of use, and optimal performance. Its robust construction, compact size, cardioid polar pattern, integrated pop filter, switchable low-frequency roll-off, and XLR connector contribute to its reliability and suitability for a wide range of recording and live sound applications.

Frequency Response and Sound Quality

The Shure SM81 is known for its excellent frequency response and sound quality, which contribute to its versatility and ability to capture accurate and detailed audio.

Flat Frequency Response

The SM81 boasts a flat frequency response, ranging from 20Hz to 20kHz. This means that it captures sound across the entire audible spectrum without significant emphasis or attenuation of specific frequencies. The flat response allows for faithful reproduction of the original sound source, ensuring accurate and natural recordings.

Extended High-Frequency Response

The SM81 excels in reproducing high-frequency content with clarity and detail. Its extended high-frequency response ensures that delicate nuances, harmonics, and overtones capture accurately. This characteristic is particularly beneficial when recording or amplifying acoustic instruments like guitars, where the shimmering highs contribute to their overall tonal richness.

Balanced Sound

The SM81 is known for its balanced sound quality. It provides a neutral and transparent representation of the recorded or amplified sound source. This characteristic allows the true essence and character of the instrument to shine through without coloration or excessive emphasis on certain frequency ranges. The result is a natural and authentic representation of the acoustic guitar’s tonal characteristics.

Accurate Transient Response

The microphone’s fast transient response enables it to capture the quick attacks and rapid changes in sound accurately. This quality is vital when recording acoustic guitars, as it allows the microphone to capture the subtle nuances and dynamics of the instrument, from delicate fingerpicking to strumming patterns.

Low Self-Noise

The SM81 has a low self-noise level, which means it produces minimal internal noise that could affect the quality of the recorded signal. This low-noise floor ensures that the microphone captures the intended sound source without introducing unwanted artifacts or disturbances.

Overall, the Shure SM81’s flat frequency response, extended high-frequency range, balanced sound, accurate transient response, and low self-noise contribute to its reputation for exceptional sound quality. These characteristics make it well-suited for capturing the full range of acoustic guitars, allowing engineers and musicians to achieve detailed, natural, and professional recordings.

Studio Performance

The Shure SM81 is widely regarded for its exceptional studio performance, particularly when it comes to capturing acoustic instruments like guitars. Many of my engineering friends prefer this mic to others for acoustic guitars.

Accurate Sound Reproduction

The SM81 is renowned for its ability to faithfully reproduce the sound of acoustic guitars in the studio environment. Its flat frequency response and balanced sound capture the instrument’s tonal characteristics with precision, ensuring an accurate representation of the original sound source.

Versatility with Guitar Types

Whether you’re recording steel-string or nylon-string acoustic guitars, the SM81 is well-suited for both. It can capture the rich tonal nuances, resonances, and harmonics of various guitar types, allowing engineers to achieve a natural and well-balanced sound.

Instrument Detail and Clarity

The SM81’s extended high-frequency response captures the intricate details and subtle nuances of acoustic guitar performances. It accurately reproduces the instrument’s harmonic overtones, allowing for clear and defined recordings. The microphone excels at capturing the transient response of the guitar, preserving the nuances of fingerpicking, strumming, and percussive techniques.

Flexible Placement Options

The SM81’s compact size and cardioid polar pattern offer flexibility in microphone placement. Positioning it close to the guitar’s soundhole creates a focused and intimate sound. Position it farther away to capture a broader soundstage. Experimenting with placement techniques allows engineers to achieve the desired sonic characteristics and blend the guitar with other instruments in the mix.

Reduced Ambient Noise

The cardioid polar pattern of the SM81 provides excellent off-axis rejection, reducing unwanted ambient noise and room reflections. This characteristic helps to isolate the guitar sound, resulting in cleaner and more focused recordings.

Durability and Reliability

The SM81’s robust construction ensures it can withstand the demands of regular studio use. Its durability and reliability make it a trusted choice for professional recording engineers. It can handle high sound pressure levels without distortion. This makes it suitable for capturing both soft and loud passages of acoustic guitar performances.

Overall, the Shure SM81’s studio performance shines when it comes to recording acoustic guitars. Its accurate sound reproduction, versatility with different guitar types, instrument detail, and clarity, flexible placement options, reduced ambient noise, and overall durability and reliability make it a go-to choice for capturing the nuances and essence of acoustic guitars in the studio setting.

Live Performance

The Shure SM81 is a versatile microphone that can deliver excellent performance in live settings, particularly for amplifying acoustic guitars.

Cardioid Polar Pattern

The SM81’s cardioid polar pattern is advantageous in live performances. It focuses on capturing sound from the front while rejecting sound from the sides and rear. This helps to isolate the acoustic guitar and minimize feedback from other instruments or stage noise. The result? A cleaner and more focused sound.

Feedback Rejection

The SM81’s directional characteristics, coupled with its off-axis rejection, make it effective in reducing the chances of feedback. This is especially valuable in live performance situations where stage monitors and high sound levels are present. The microphone allows you to achieve higher gain before feedback, providing more control and stability during live performances.

Durable Construction

The SM81’s robust metal construction ensures durability, making it suitable for the demands of live performances. It can withstand the rigors of touring, frequent setup and teardown, and other challenges of the live environment. The microphone’s reliable build quality ensures consistent performance throughout various gigs and venues.

Accurate Sound Reproduction

The SM81’s flat frequency response and balanced sound quality contribute to accurate sound reproduction in live settings. It captures the nuances and tonal characteristics of the acoustic guitar with clarity and fidelity. This allows the instrument to shine through the mix and reach the audience with authenticity.

Versatile Application

While primarily used for acoustic guitars, the SM81’s versatility extends to other applications in live performances. It captures other acoustic instruments such as pianos, strings, percussion, and more. The microphone’s ability to handle high sound pressure levels and accurately reproduce transient details makes it suitable for a range of live performance scenarios.

Ease of Positioning

The SM81’s compact size and lightweight design make it easy to position on stage. It mounts easily on a stand or clipped onto an instrument using appropriate microphone mounts or clips. The microphone’s flexible placement options allow you to find the optimal position. This captures the acoustic guitar’s sound while considering stage setup and performer preferences.

Overall, the Shure SM81’s features and performance make it a reliable choice for live performances, particularly for amplifying acoustic guitars. Its cardioid polar pattern, feedback rejection, durable construction, accurate sound reproduction, versatility, and ease of positioning contribute to a high-quality and consistent audio experience in live settings.

Recordings Featuring the Shure SM81

“Hotel California” by Eagles: The iconic acoustic guitar intro on this classic Eagles song was recorded using the Shure SM81. The microphone captured the intricate fingerpicking and rich tonal qualities of the acoustic guitar, contributing to the song’s timeless sound.

“Blackbird” by The Beatles: The delicate and intricate acoustic guitar part in “Blackbird” by The Beatles was recorded using an SM81. The microphone captured the detailed picking and the warm, resonant tones of the instrument, adding to the song’s intimate and captivating atmosphere.

Various James Taylor recordings: James Taylor, known for his exceptional acoustic guitar playing and soulful vocals, has used the SM81 on many of his recordings. The microphone has helped capture the nuanced fingerstyle technique and the warm, expressive qualities of his acoustic guitar sound.

“Fast Car” by Tracy Chapman: The captivating acoustic guitar sound on Tracy Chapman’s hit song “Fast Car” was captured using the Shure SM81. The microphone allowed the intricacies of the guitar playing and the emotional resonance of the instrument to shine through in the recording.

“Wonderwall” by Oasis: The acoustic guitar part on Oasis’ popular song “Wonderwall” was recorded using an SM81. The microphone captured the strumming and rhythmic qualities of the guitar, contributing to the song’s distinctive sound and memorable hooks.

Shure SM81 Pros and Cons

Pros:

1. Versatility: The Shure SM81 microphone offers exceptional versatility, suitable for capturing various instruments and vocals with remarkable clarity and accuracy.
2. Durability: Built with robust construction and high-quality materials, the SM81 microphone is highly durable, making it reliable for rigorous live performances and studio applications.
3. Detailed Sound Reproduction: With its precise and transparent audio reproduction, the SM81 microphone excels at capturing intricate details and nuances, resulting in a natural and true-to-life sound.

Cons:

1. Price: The Shure SM81 microphone is relatively expensive compared to other options in its category, which may be a deterrent for those on a tight budget.
2. Sensitivity to Handling Noise: Due to its high sensitivity, the SM81 microphone can pick up handling noise and vibrations easily, requiring careful handling or additional shock-mount accessories.

Specifications

Specification	Details
Microphone Type	Condenser
Polar Pattern	Cardioid
Frequency Response	20Hz – 20kHz
Sensitivity	-45 dBV/Pa (5.62 mV/Pa)
Equivalent Noise Level (A-weighted)	16 dB
Maximum Sound Pressure Level (SPL)	136 dB (1 kHz at 1% THD)
Signal-to-Noise Ratio	78 dB (1 kHz at 1 Pa)
Self-Noise	18 dB SPL
Impedance	150 ohms
Connector	XLR
Dimensions	20 cm x 2.5 cm (7.9″ x 1″)
Weight	238 grams (8.4 oz)

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Alternatives to the Shure SM81

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Wrap Up

The Shure SM81 is a reliable and versatile microphone that excels in both recording studio and live acoustic guitar scenarios. Its accurate sound reproduction, flat frequency response, and exceptional build quality make it a preferred choice for capturing the essence and subtleties of acoustic instruments. Whether you’re an engineer aiming for studio-quality recordings or a live performer seeking clarity and fidelity, the SM81 is a dependable tool that delivers excellent results time and time again.

Looking for other options for microphones? Check out my post on finding the Best Mic For Acoustic Guitar, including ribbon microphones.

Editorial Process:

My reviews are made by a team of one, myself, before being written and come from real-world experience. Read my editorial process here.

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