Audio Technica 2021 cardioid mics

Top: omni-directional mic capsules;
Bottom: cardioid directional caps;
built by Chris Church, of Church Audio

The Sonic Archives Arsenal of Miniature Recording Gear
how to carry a virtual live recording studio in a backpack

How does one capture the energy of a live performance in a recording? Well, there's more to making a great recording than having a good ear, although that is definitely a good resource to have. You've got to have some decent equipment as well. I tend to use my equipment in a somewhat unconventional manner, but then again, I'm not trying to get conventional results, and I'm not trying to compete with bigger, "professional" recording facilities. Some folks really believe they need a 24-channel mobile studio for a live recording. All the gear I need to record a show generally fits in a backpack or a duffle bag, and I'll probably show up at your gig on a mountain bike.

What I can offer is a simple, economical, down-to-earth approach to live recording. What you do with it is - literally - your business. After all, it's your music; I'm just the engineer.

The Sonic Archives Live Recording arsenal:

Audio Technica AT-2020 side-address cardioid condenser mics (2)
Audio Technica AT-2021 small-diaphragm cardioid condenser mics (4)
Church Audio B-99M stereo pro-binaural mics (stereo pair)
Church Audio ST-11 stereo binaural mics [cards & omnis; stereo pair]
Church Audio ST-11 single-line binaural mics [cards & omnis]
Realistic 33-1090A PZMs [pressure zone / boundary mics]
Crown Sound Grabber II PZMs [pressure zone (boundary) mics]

Zoom R24 Recorder:Interface:Controller:Sampler (16/24-bit 44.1/48kHz) [not pictured yet!]
Edirol R-04 (16/24-bit 44.1/48/96kHz) [not pictured yet!]
Edirol R-09 (24/96) digital recorder
M-Audio Microtrack 24/96 digital recorder
SHARP IM-DR420 mini-disc digital/analog recorder
Canon G9 digital camera

Church Audio ST-20 stereo pre-amp [-20/+20dB; optional 8kHz filter]
Church Audio custom-built 4-channel pre-amp [+10/+30dB high-pass filter]
Mackie Micro Series 1202 12-Channel Mic/Line Mixer
BBE Sonic Maximizer
Kenwood GE-1100 12-band EQ
Yamaha EMX 62M powered mixer [6 inputs, 7-band graphic EQ, 200-watts]
Yamaha BR12M 12" 2-way monitor speakers [2]
Mac audio applications, including Audacity, Garage Band, Sound Booth, ProTools
PC applications including CD Wav editor, SoundForge, Magix Music Studio deLuxe 12

Environmental, stage, soundboard and "matrix" recording options are available, and possibly even a few ideas we haven't tried yet!

Audio Technica 2021 cardioid mics mics

Audio Technica AT-2020 cardioid mics

Audio Technica AT-2020 (cardioid) mics
Small-diaphragm cardioid condenser microphone

High SPL handling and wide dynamic range
Low-mass diaphragm provides extended frequency response and superior transient response
Cardioid polar pattern reduces pickup of sounds from the sides and rear, improving isolation of desired sound source

Technical specs:
Fixed-charge back plate, permanently polarized condenser
Element: Fixed-charge back plate, permanently polarized condenser
Polar pattern: Cardioid
Frequency response: 20-20,000 Hz
Open circuit sensitivity: –37 dB (14.1 mV) re 1V at 1 Pa
Impedance: 100 ohms
Maximum input sound level: 144 dB SPL, 1 kHz at 1% T.H.D.
Noise: 20 dB SPL
Dynamic range (typical): 124 dB, 1 kHz at Max SPL
Signal-to-noise ratio: 74 dB, 1 kHz at 1 Pa
Phantom power requirements: 48V DC, 2 mA typical

Audio Technica 2021 cardioid mics mics

Audio Technica AT-2021 cardioid mics, shown here with Edirol R-04

Audio Technica AT-2021 (cardioid) mics
Small-diaphragm cardioid condenser microphone

Ideal for acoustic guitar, overheads, piano and group vocals
Condenser design for studio-quality vocal and instrument applications
Excels in high-SPL applications
Extended response for smooth, natural sonic characteristics
Low-mass element for superb transient response
Corrosion-resistant contacts from gold-plated XLRM-type connector
Rugged design and construction for reliable performance
Cardioid polar pattern reduces pickup of sounds from the sides and rear, improving isolation of desired sound source

Technical specs:
Element: Fixed-charge back plate, permanently polarized condenser
Polar pattern: Cardioid
Frequency response: 20-20,000 Hz
Open circuit sensitivity: –37 dB (14.1 mV) re 1V at 1 Pa
Impedance: 100 ohms
Maximum input sound level: 144 dB SPL, 1 kHz at 1% T.H.D.
Noise: 20 dB SPL
Dynamic range (typical): 124 dB, 1 kHz at Max SPL
Signal-to-noise ratio: 74 dB, 1 kHz at 1 Pa
Phantom power requirements: 48V DC, 2 mA typical

Church-Audio B99A pro-binaural mics

Church-Audio B99A pro-binaural mics, shown with and without windscreens

Church Audio B-99A stereo omni-directional (pro-binaural) mics

Personally, I happen to like the mics made by Church Audio, in terms of their portability and reproduction. I thought I'd let the man who built these mics speak for himself.

from the Church-Audio eBay store:

This stereo microphone is designed for high quality capture of music, speech, and nature recording. It produces a very natural sound with a very wide flat frequency response, the measured response is 20hz to 40khz. These mics are perfect for any type of recorder that provides plug in power and a 3.5 mm stereo mic input jack.

This microphone includes 4.5 feet of high quality Mogami cable, for quality audio. We use gold plated Neutrik jacks because they are the best available and last as long as our mics do. We use a shielded microphone housing to eliminate noise. These mics also include windscreens for recording outdoors.

Technical specs:
Type Electret Condenser Non-directional Sensitivity -43db@1 khz
Operating voltage: 1.1 volt to 10 volt
Max. sound pressure: 120dB SPL
Impedance: 1.6k
S/N ratio: 58dB
Frequency response: 20hz to 40kHz

Church-Audio ST-11 stereo mics and caps

Church-Audio ST-11 stereo pair; pictured with windscreens and interchangeable set of omni caps

Church Audio ST-11 Stereo binaural mics
(interchangeable cardioid or omni-directional capsules; 20-40kHz)

Chris Church sent me a prototype version of these mics, and frankly, I was blown away, the first time I used them ... and the time after that ... and the time after that as well!

The cardioid caps will handle loud dynamic volumes at extremely close range (for example, mounted on stage at a loud rock show, three feet from the guitar amp), with remarkable clarity and no distortion. I've tested these mics mounted on a hat, from the back of a room at an acoustic concert, and came away with a recording so clear I could hear the detailed resonance every time the singer parted his lips! In a non-stealth recording situation, approximately ten feet in front of an overhead P.A., I get a balanced mix that you wouldn't be able to get from a soundboard recording! Of course, the omni caps are pretty amazing too - if you want to capture more of a room's ambient sound, they will do especially well in that application.

These mics work well with any unit that requires no more than a mini (1/8-inch) plug, and do not need an external power source. When combined with a battery box or pre-amp (such as the Church Audio ST-20), there is the option of boosting or reducing the range, for sharper dynamics.

Church-Audio ST-20 pre-amp

Church Audio ST-20 pre-amp

Church Audio ST-20 pre-amp

All the technical info is in Chris Church's own words:

• Very low self noise (below -120dB S/N ratio with no input connected)
• Very good stereo separation and excellent phase response
• Powered by a single 9-volt battery
• Very low power consumption
• Gain range: -20 to +20
• Ideal for making the most of your signal-to-noise ratio, and for acting as a pad in loud situations like concert recording
• Provides a full 9 volts plug-in power for all stereo mics that require it

Built-in ST-20A High Pass Filter:
Rolls the bottom end off at 80Hz, at 6dB per octave, and gets rid of rumble from large arena recordings or recording situations where there is too much low frequency.

Church-Audio extended mics w/ card & omni caps

Church Audio custom extended mics:
top: omni
bottom: cardioid

Church Audio ST-11 extended single-line binaural mics
(interchangeable cardioid or omni-directional capsules; 20-40kHz)

These mics were built to satisfy a need for on-stage mic placement within a close range to the instruments, for non-stealth recording. Because of the extended shell, they can be placed on mic clips, or suspended in a shock mount.

The capsules are essentially the same as the smaller stereo mics, and will deliver the same amazing results, but these particular mics were designed to work with a single-line application, so the gain for each mic can be controlled separately.

These mics, used with the 4-channel pre-amp shown below, allow me to get as close to the musicians as I need, and essentially use the 4-channel pre-amp as a mixing console. The 2-channel stereo output from the pre-amp remains a pure "live" signal, although the additional mixing capabilities improve the dynamics of each separate channel.

Church-Audio custom built 4-channel pre-amp

Church Audio custom 4-channel pre-amp; built exclusively for Sonic Archives

Church Audio custom-built single-line 4-channel pre-amp

Obviously not designed for stealth recording, this is quite literally a one-of-a kind device in the realm of miniature live recording gear. I had talked with Chris Church about the need for something that worked along the same lines as other portable recording devices where a battery box/pre-amp would be required, but which would also allow me to record separate channels. This pre-amp allows me to actually mix "on-the-fly" binaural recordings, and is especially useful in an acoustic environment. Two separate banks each provide left and right channel separation, so the input signals can be rendered as a naturally balanced stereo output. Think of it as a 4-track input device with 2-channel on-the-fly mix-down capability.

The built-in high-pass filter allows room to record the faintest of sound levels, with the ability to boost levels an additional +10 or +30dB. In a situation where there is no P.A. system or mics involved, this allows the pre-amp to function as a virtual "soundboard" - particularly since the single-line mics can be placed right in front of each individual instrument. Another application for this pre-amp is to create a "live ambient matrix" recording, using a combination of cardioid and omni mics to dial in specific instrumentation as well as the acoustic ambience of the room itself.

Edirol R-09

Edirol R-09 digital recorder

Edirol R-09 24-bit WAV/MP3 Digital Recorder

The Edirol records on flash RAM (i.e., SD & SDHC Compact Flash Cards - the same type of card used by many digital cameras), so there are no moving parts to create any extraneous noise.

Capture source material at a crystal-clean 24-bit resolution with your choice of 44.1 or 48kHz sample rates. You can record and play back in .mp3 format as well (up to 320kbps). Once recorded, your files can be monitored through the R-09’s headphone jack and/or exported to a computer via USB.

features include:
I.A.R.C. (Isolated Adaptive Recording Circuit)
[dedicated analog circuit; electrolytic capacitors provide stable, reliable power to the analog circuits, eliminating DC interference.
input gain volume control to manually adjust recording levels.
Built-in stereo microphone, complete with a dedicated input control, mono/stereo selector, low-cut filter, and gain boost.
1/8" external mic input
USB 2.0 Rapid File Transfer for importing/exporting audio files via computer
[For example, a 600 MB recording at 44.1 kHz/16-bit takes only 5 minutes to transfer, only 1/12 of the time it would take to transfer the same recording from a MiniDisc or tape (cassette/DAT) recorder.]

A 4GB card stores a little over 6 hours of uncompressed PCM (.wav) audio, and a 2GB card can hold a little over an hour of 24-bit data.

M-Audio Microtrack

M-Audio Microtrack; shown with cables and stereo mic

M-Audio MicroTrack 24/96 Digital Recorder

Like its' well-known counterpart, the Edirol, this smart little unit records on flash RAM.

The Microtrack has the capability to record uncompressed PCM (.wav) files: 16 or 24-bit at 44.1, 48, 88.2 or 96kHz; and can also record in .mp3 format: 96 to 320kbps at 44.1 or 48kHz. Keep in mind, most people generally don't hear the difference between a 190 kbps .mp3 and a red-book standard audio CD (16-bit/44.1kHz). The recording volume can also be adjusted while recording, and there are high/medium/low settings for mic sensitivity.

A 4GB card stores a little over 6 hours of uncompressed PCM (.wav) audio, and a 2GB card can hold a little over an hour of 24-bit data.

features include:
• phantom power
• 1/8-inch mini-phone input for electret condenser mics
• 1/4-inch TRS (tip-ring-sleeve) line/microphone inputs with phantom power
• S/PDIF digital audio input
• RCA line outputs
• 1/8" stereo output for headphones
• USB 2.0 port

Sharp IM-DR420 minidisc recorder

SHARP IM-DR420 minidisc recorder; shown with cables and stereo mic

SHARP IM-DR420 mini-disc recorder

Although I'm no longer using this for audio recording, due to the built-in ATRAC compression [see below], this was my unit of choice when I decided to take the plunge into the realm of mini-disc recording. One of the big factors was the ability to adjust the record level while recording, with no interference to the signal input. Later, this became a standard, but at the time, SHARP was the first company to provide this feature.

This particular unit preceded the present wave of Hi-MD units, and does not have USB digital uploading capability, so the output signal must be transferred via analog cables to a HD. In some ways, this combines the best of both the digital and analog realm, in terms of recording and editing. At the same time, this can also be seen as one of limitations of this unit. For accurate transfers, the discs should be played on a component-type deck via optical or coaxial outputs.

It should be noted that the unit itself applies a proprietary form of digital compression (ATRAC), which means that the resulting wave form will be lossy [which is specifically why I no longer use it for live recording]. An oversimplification of the ATRAC compression is that it divides the input signal into three sub-bands, which are then re-allocated by an algorithm, which then applies a compression ratio of less than 5:1. This might roughly be considered the equivalent of MPEG-Layer 1, or a 128kbps .mp3. Obviously, this is not meant to compete with produced, studio-quality sound, but for many listeners, this can still provide decent audio quality for a 2-channel stereo live recording, and will also work quite well for audio on the web.

All said, if I hadn't explained all of this, your ears might possibly never know the difference. Still, with so many other un-compressed options to work with, I've retired the SHARP as a recording unit, and decided to use it as both a walkman and a mini-stereo, since it does have digital downloading capability (via USB) from my computer. In a way, this has now become the closest thing to an iPod I will ever own, oddly enough.

Some of the other features that make this unit particularly useful for live recording, include:

• 4-pole earphones, 4-pole to 3 pole conversion cable
• optical cable
• analog cable (1/8" stereo to RCA x 2)
• USB cable (input)
• non-LCD remote
• automatic (low/high range) and manual recording level control
• 1-bit digital amp
• line synchro-start recording (microphone synchro-start [i.e. voice activated] recording)
• mic / line input (auto and manual recording level function)

Tandy / Realistic PZM

Realistic 33-1090A PZM

Realistic 33-1090A pressure zone (boundary) mics (PZMs)

I've used these mics for basic live recording, for more than a decade, and they still can't be beat in certain situations. Because of their unique design, they will provide optimum results if mounted on a flat surface - ideally, around 4'X4'. A typical application for recording orchestral instruments involved placing them on the front of the stage floor; this technique also worked pretty well for an acoustic jazz combo I used to record at a coffeehouse in Tampa, several years ago. Since they are omnidirectional, they "sort" the frequencies out pretty evenly, depending on the relative proximity of each mic, so you don't have to worry too much about "aiming" the mic at the sound source.

I've had some success mounting these mics of the opposite side walls - and even ceilings - of various stages, in order to accommodate the balance of amplified and non-amplified instruments, also incorporating stage monitor mixes. The most common application I've used was to actually mount them on a stereo bar in the middle of a venue, occasionally mounted on a larger flat backing plate, but most of the time, just using them unaltered in any way. Experimenting with phasing issues, I found that when mounting individual mics on separate stands in a large room or open air environment, they could be placed up to 30' apart, before noticeable invasive phasing occurred.

Technical specs:
Manufactured by Tandy (Radio Shack) under license from Crown.
Omnidirectional pick-up pattern
Condenser capsule
1.5V AA battery operation
Fixed lead with built in battery preamp and 1/4" connector

Crown Sound Grabber 2 PZM

Crown Sound Grabber II PZM

Crown Sound Grabber II PZM Microphones

While it can be argued that the frequency response for this PZM is somewhat more restricted than the Tandy-manufactured model, it still has plenty of practical applications, particularly in the range of the human voice. These mics are not the best-suited for densely-textured musical performances, although they can be quite useful in capturing the dynamics of limited-range acoustic instruments that favor the higher frequencies, or where the lower register isn't as essential. Keep in mind that while the range of 20Hz - 20kHz is what the human ear is capable of hearing, what many of us actually do hear tends to fall in the 50Hz - 16kHz range, so this particular mic can be pretty accommodating to most ears. Ideal when mounted on a large flat surface, in environments with little or no reverb.

Technical specs:
Transducer: Electret condenser
Frequency response (typical): 50 Hz to 16 kHz
Polar pattern: Hemispherical (half-omni) on a large surface.
Impedance: 1,600 ohms, unbalanced. Recommended minimum load impedance 10,000 ohms.
Open-circuit Sensitivity: 20 mV/Pa* (-54 dBV/Pa).
Power sensitivity: –42 dBm.
Equivalent noise level (self noise): 21 dB SPL typical, A-weighted (0 dB = .0002 dyne/cm2).
S/N ratio: 73 dB at 94 dB SPL.
Maximum SPL: 120 dB SPL produces 3% distortion.

Mackie 1202 mixer

Mackie 1202 12-channel mixer

Mackie Micro Series 1202 12-Channel Mic/Line Mixer

This Mackie mixer is great for live performances with a small band. It's also a handy audio editing tool for video, and also allows you to make clean adjustments to the relative balance in your home stereo system. It has 4 mic or line inputs [both XLR and 1/4" phono jacks], a pair of RCA inputs for line level sources [such as CD players or tape decks], and 4 additional sets of mono/stereo phono inputs. 12 inputs in all, plus a dedicated tape input.

This mixer features outputs for a power amplifier or self-powered speakers with a stereo mix. It also has built in equalization adjustments for each input source, and the ability to work with either powered mics or those that get their power from the mixer.

Technical specs:
Channels 1-4 XLR Mic, 1/4" Balanced/Unbalanced Line Level with Direct Inserts & Trim Control
Channels 5-12 1/4" Balanced/Unbalanced Stereo Line inputs
Tape in (dual RCA) & Tape Out (dual RCA)
2 Mono Aux Sends & 2 Stereo Aux Returns 1/4". Balanced/Unbalanced line level
Main outs Left, Right. 1/4" Balanced/Unbalanced Line Level
All channels include Gain, Pan, Hi and Lo EQ, 2 Aux Sends
Stereo Headphone Output 1/4"
+48V Phantom Power

Yamaha EMX 62M Powered Amp

Yamaha EMX 62M powered amplifier

Yamaha EMX 62M Powered Amplifier

If your recording situation calls for a P.A., and you don't have one handy, this powered mixer is an amp and a streamlined mixer in one compact, solid unit. It delivers more volume than most mid-sized rooms need, as well as mixing capabilities for 6 inputs, 7-band graphic EQ, and 3 built-in, adjustable levels of digital reverb. One of the more convenient features about this compact unit, is that since there are fewer components to set up, there can be more time to concentrate on the music.

Technical specs:
Maximum Output Power:
@0.5% THD (total harmonic distortion) at 1kHz 200W/4ohms
Input Connectors:
channels 1 - 4: XLR and TRS Phone (1/4")
channels 5 - 6: 2 x TRS Phone (1/4")
Graphic Equalizer:
7 band [125Hz, 250Hz, 500Hz, 1kHz, 2kHz, 3kHz, 4kHz, 8kHz]
Digital Effects:
3 programs - Vocal Reverb, Large Hall & Small Hall

Yamaha BR12M monitors

Yamaha BR12M 12" monitors

Yamaha BR12M 12" 2-Way Monitor Speakers

The perfect match for the EMX 62M Powered Mixer, these speakers can be used as P.A. speakers or individual monitors. If you bring the sound, these speakers will deliver it, from a basement, to a small club or a block party.

Technical specs:
Frequency Response (-10dB): 65Hz-20kHz
8 ohms nominal impedance
97dB sensitivity (1W, 1m)
300W program/600W peak handling
2 - 1/4" phone input jacks
12" high-power woofers
Tweeter (diaphragm): 1" pure titanium drivers
40 degree H x 90 degree V nominal dispersion
22-1/2" W x 16"H x 13-1/4"D each

The photos shown on this page are all pictures of gear I own and use. If some of the mics looks like they've been around the block a few times, well - they have. Then again, it's not the mics I'm selling (although I definitely endorse and recommend them!) - it's what can be done with them.

This gear is definitely road-worthy, and has made converts out of many people who initially doubted what it could deliver. I'm not saying I can do everything with this equipment, but I bet I could surprise you with the results I can get, in less time and for less money, than you might think.

I believe the best way to run a business is to do the best job you can, and keep your costs - and your prices - reasonably low. Word of mouth should take care of the rest. Combined with a little imagination - and of course, a good pair of ears! - it might be interesting to see how some of these ideas could work with your sound!

Church-Audio mic collection

Mics built by Chris Church of Church Audio

all photos © J. Free; 2008

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