Microphones are one of the most important pieces of equipment in any recording studio. The type of microphone used on an instrument or vocal can have a significant impact on the overall sound quality of a recording. As music production technologies have advanced over the decades, studio microphones have evolved to offer producers more options for capturing sound. Selecting the right microphone for the job is an essential part of achieving a full, balanced mix.
A Brief History of Studio Microphones
The invention of the microphone in the late 1800s revolutionized sound recording and transmission. Early microphones were crude devices, but they laid the groundwork for studio microphones that would eventually transform music production.
Early Microphone Models
Some of the earliest microphone models included the carbon microphone, the condenser microphone, and the dynamic microphone:
- Carbon microphones use carbon granules to vary electrical resistance and output audio signals. They were used in early telephones and radios.
- Condenser microphones use an electrically charged thin metal diaphragm that vibrates to convert sound into an electrical signal. These provided clearer audio than carbon mics.
- Dynamic microphones use electromagnetic induction by a coil of wire attached to a movable diaphragm. They introduced ruggedness and reliability.
These primitive microphone types paved the way for more advanced microphones to come.
The Ribbon Microphone
The revolutionary ribbon microphone was introduced by RCA in the early 1930s. Instead of a diaphragm, it uses a thin corrugated aluminum ribbon suspended in a magnetic field to capture sound vibrations.
Ribbon microphones offered a more natural, well-rounded sound, and quickly became a staple of recording studios. They lent an intimate warmth to vocals and provided smooth, transparent recordings of acoustic instruments.
The Condenser Microphone
German manufacturer Georg Neumann introduced the first condenser microphone with a vacuum tube amplifier in 1928. Unlike previous condenser mics, Neumann’s design provided impressive sound quality with wide dynamic range and frequency response.
This kicked off the reign of condenser microphones as the studio microphone of choice through the 1950s and beyond. Early high-end condenser mics from Neumann and Telefunken contributed to the rich vocal tones and audio fidelity captured on historic jazz and classical recordings.
The Electret Condenser Microphone
The invention of the electret in the 1960s provided new possibilities for condenser microphone design. An electret is a permanently charged material that replaces the external power historically needed to charge a condenser microphone’s diaphragm.
This led to the durable, affordable electret condenser microphones (ECMs) found in most modern recording devices. From inexpensive podcast mics to high-end studio condensers, electret technology makes condenser microphones accessible for all levels of recording.
Modern Studio Microphone Types
Thanks to a century of microphone advances, today’s producers can choose from a wide range of specialized microphone models to capture any instrument, voice or ambient sound. Let's examine the key types of microphones used in modern music production:
Dynamic Microphones
Dynamic microphones remain a studio staple, valued for their ruggedness, affordable price, and ability to handle high volume sources. They work via electromagnetic induction to convert sound into an audio signal.
Use cases: Close-miked vocals, guitars, drums and other loud instruments. Live performances.
Examples: Shure SM57, Sennheiser MD 421, AKG D112
Condenser Microphones
Condenser microphones are known for excellent transient response and high sensitivity to capture nuance and detail. They convert acoustic vibrations to electrical signals using a thin diaphragm and capacitor plate.
Use cases: Overhead drums, acoustic instruments, percussion, vocals, speech
Examples: Neumann U87, AKG C414, Rode NT1A
Ribbon Microphones
Ribbon microphones work similarly to dynamic mics but use a suspended aluminum ribbon and magnet system. They provide a smooth, natural tone and excellent transient response.
Use cases: Vocals, guitar and drum overheads, brass, strings, ambient room mics
Examples: Royer R-121, Beyerdynamic M160, sE Electronics Voodoo VR2
Tube Microphones
Tube microphones incorporate vacuum tube amplifiers to replicate the warm vintage tone of early condenser and ribbon microphones. Modern tube mics provide detailed sound with rich harmonics.
Use cases: Vocals, acoustic instruments, drum overheads, guitar amps
Examples: Neumann U47, AKG C12, Telefunken Ela M 251
Critical Microphone Specifications
From rugged dynamics to smooth ribbons to pristine condensers, today’s microphones provide endless options. Here are some key technical specifications to consider when selecting a microphone for the studio:
Frequency Response
This indicates the mic’s range of accurately reproduced frequencies, measured in Hz. Wider is generally better.
- Vocals:Â 40Hz to 15kHz
- Acoustic instruments:Â 20Hz to 20kHz
Polar Patterns
The pickup pattern indicates where a mic will focus its sensitivity. Choose patterns that reject unwanted sounds.
- Cardioid:Â Picks up sound source directly in front
- Omnidirectional:Â Picks up sound equally around the mic
- Bidirectional:Â Picks up from front and rear of mic
Sensitivity
Measures how well the mic converts acoustic sound pressure to output voltage. Higher sensitivity means the mic can detect subtler sounds.
- Condensers:Â -30 to -50 dBV/Pa
- Dynamics:Â -55 to -70 dBV/Pa
Impedance
The output impedance of the microphone, which impacts the strength of its signal before amplification. Lower impedance reduces interference.
- 150-250 ohms:Â Best for condensers and ribbons
- 1000-10,000 ohms:Â Normal for dynamics
Microphone Techniques for Recording Instruments
One of the biggest factors impacting recording quality is microphone selection and placement. Let's look at some common miking techniques used during music production:
Recording Vocals
- Large diaphragm condenser:Â Warm, detailed sound for lead vocals
- Small diaphragm condenser:Â More precise transient capture
- Dynamic:Â Rugged reliability for live or loud singers
- Proximity effect:Â Boosted bass when close (1-6 inches)
- Pop filter:Â Blocks plosives on close miked vocals
Recording Acoustic Guitar
- Small diaphragm condenser:Â Articulate string and body detail
- Cardioid pattern:Â Rejects sounds not directly in front
- Over shoulder:Â Place 6-12 inches back from sound hole
- Room mic:Â Add ambience with omni condenser further away
Recording Electric Guitar Amps
- Dynamic mic:Â Handles high SPL of guitar amps
- Condenser mic:Â Catches more overtone nuance
- On axis:Â Place 1-2 feet from amp at cone level
- Off axis:Â Reduces harshness, bright overtones
Recording Drums
- Overheads:Â Pair of condensers in XY or spaced pair
- Kick drum:Â Large diaphragm dynamic just inside port
- Snare:Â Small diaphragm condenser on top
- Toms:Â Dynamics on top or on side aimed at head
Recording Piano
- Stereo pair:Â Matched condensers spaced evenly over piano
- **Ribbon mics:**Smooth, mellow tone
- Room mics:Â Additional omni mics for ambience
- Close miking:Â Condensers on soundboard to catch detail
Microphone Preamplifiers and Audio Interfaces
Quality microphone preamplifiers and audio interfaces help produce optimal sound when recording. Microphone preamps strengthen the mic's quiet signal before processing and recording. Audio interfaces convert the analog signal to digital and enable connectivity.
When selecting preamps and interfaces, consider:
- Gain:Â How much amplification can the preamp provide? At least 50-60dB is ideal.
- Max input:Â The highest input level the interface can handle without distorting. +16 dBu or higher is best.
- Bit depth/sample rate:Â Look for 24 bit/192 kHz for studio recording. This captures more dynamic range.
- Latency:Â The delay between input and DAW playback. Under 10ms is imperceptible.
- EIN:Â Equivalent input noise indicates how little self-noise the preamp adds. Around -125 dBu is excellent.
- DI inputs:Â Direct boxes for instruments like bass and keyboards.
- Connectivity:Â Number of mic/line inputs needed. Consider expansion.
Mixing Tips for Optimal Recordings
No matter how pristine your microphones, proper mixing is vital to achieve professional results:
- Use EQ thoughtfully:Â Boost key tones, avoid drastic cuts
- Compress gently:Â 2:1 ratio, low threshold & makeup gain
- Add depth via reverb:Â Short plates for instruments, halls for vocals
- Pan for space:Â 60L to 60R for spread, double-track for centered vocal
- Set levels properly:Â Peak around -18 dBFS, normalize if too low
- Listen on many systems:Â Consumer speakers, earbuds, car stereo, etc.
- Take breaks:Â Fresh ears catch issues like buildup or masking
The Impact of Microphones on Music History
Imagine classic albums like Kind of Blue by Miles Davis or Tapestry by Carole King without the warm intimate vocals and acoustic instruments captured by vintage microphones. The unique sonic signatures of cherished mics not only shaped timeless recordings, but influenced the evolution of entire genres:
Jazz
Ribbon mics like RCA 44 captured the smoky ambience of New York jazz clubs while Neumann U47s lent vocalists sultry presence on vinyl records. These helped define jazz's smooth, mellow aesthetic.
Rock & Roll
The Shure SM57's ability to handle skull-rattling volume made it a staple for miking electric guitar amps and powerhouse drummers like John Bonham. Its signature rock sound carries on today.
Hip Hop
The rise of the AKG D12 for booming kick drums and Sennheiser MD 409 on toms forged the punchy beats behind sampled breaks that spawned hip hop. Neumann KM84s also captured crisp cymbals popular in early drum machines.
Pop Music
Neumann U87s lent intimacy to the crooning vocals of Elvis, Frank Sinatra and pop divas. On the studio side, LA2As glued the overdubs that created Phil Spector's famous "Wall of Sound" on countless pop singles.
Clearly, the history of music production goes hand in hand with the evolution of the microphones used to capture it. Careful selection of today's top mics enables modern producers to craft recordings that honor vintage tones while pushing music forward.
FAQ
What are the main types of microphones used in studios today?
The four most common modern studio microphone types are:
- Dynamic - Rugged, handles high SPL. Good for drums and amps.
- Condenser - Sensitive and detailed. Ideal for vocals, acoustic instruments.
- Ribbon - Smooth, natural tone. Good for soft instruments, room mics.
- Tube - Warm, vintage vibe like classic ribbon/condenser mics.
Why are condenser mics preferable for acoustic instruments?
Condenser microphones excel at capturing the nuanced textures of acoustic instruments. Their extremely thin diaphragm can follow the most delicate vibrations, translating them into intimate recordings. The extended frequency response also helps reproduce the harmonic richness of instruments accurately.
Should vocals be recorded with a dynamic or condenser mic?
It depends on the vocalist. For loud, belting singers, a rugged dynamic mic may avoid distortion. Softer singers benefit from the detail of condensers. Opt for a large diaphragm condenser for rich, intimate vocal recordings. A pop filter helps reduce plosives.
What are the advantages of using two overhead mics on drums?
A spaced pair of overhead mics enables a stereo image of the cymbals and toms. Typically small or large diaphragm condensers. Typical placements include XY configuration (angled at 90-110 degrees) or spaced pair (3-6 feet apart, panned left and right).
Why are ribbon mics ideal for piano?
Ribbon mics deliver smooth frequency response perfect for the complex harmonics of pianos. They avoid the harshness that can plague condenser mics on piano overtones. For mellow classical or jazz piano, a ribbon captures the lush resonance of the instrument.
How can I improve my home studio recordings?
Focus first on microphone selection and placement - not just the mic, but where it's positioned for the instrument. Learn optimal placement techniques. Upgrade to an audio interface with robust preamps and 24-bit/192kHz sampling. Add acoustic treatment to tame reflections. And mix with quality headphones or monitors.
