This is about the microphones themselves. For their use in recording, seeAudio.In comparative tables, model numbers in italics indicate specialized microphones (e.g., percussions).
(2017-05-25) Reversible local oscillations.
(2014-06-05) Exploiting the variation with pressure of another physica; variable.
Historically, the problem of converting sound into an electrical signal wasfirst solved by devising a resistor sensitive to sound (this dominatedthe telephone industry for 60 years). Now, most microphones arebased on the variation with sound pressure of either an inductance or a capacitance.
Alternative possibilities include piezoelectric microphones, which rely on the voltages generated by varying pressure in certain solids.
Unlike all of the above, optical microphones can measure the variation of air pressuredirectly, without the help of any kind of moving membrane, but they're not yet commonplace.
Here's a complete classification of the different types of microphones:
Resistive microphones, using liquids, powders or granules:
Transforming one physical quantity into another is called transducing. Ultimately, all microphones are transducers of sound waves into electrical signals (mostly, variations in voltage).
To do this, various intermediary techniques can be employed. In some condenser microphones, for example, the sound-sensitive capacity of the capsuleis part of a low-noise radio-frequency (RF) circuit. That way, sound modulates the frequency of theprimary circuit, which is then demodulated to retrieve the signal. I'm told that Sennheiser's MKH series works this way, including the legendaryMKH 416. (That's called RF biasing.)
(2014-06-05) Condenser (varying capacitor) and dynamic (varying inductor).
Here, we'll focus only on capacitive and inductive microphones (condenser microphones and dynamic microphones) which are currentlythe most commonly used inaudio applications. They are electrical duals of each other and it's enlighteningto discuss them in parallel...
An ideal capacitor (resp. inductor) is a two-lead component characterized by two parameters, an electrical one and a geometrical one: voltage U and capacitance C (resp. current I and inductance L) whose product is equal to an extensive electromagneticquantity stored by rhe device: the electric charge q (resp. the magnetic flux ). In the absence of external electromagnetic fields, we have:
q = C U = L I
Differentiating this with respect to time, we obtain:
I = C' U + C U' U = L' I + L I'
As mechanically-induced motion causes C (resp. L) to vary, a signal is generated which is proportional to the mechanical speedsinvolved. If the geometry is tied to the position of a mechanicalmembrane, that dynamical position is easily retrieved by integration...
The above analysis is fairly realistic for capacitive (condenser) microphones but is utterly inadequatefor inductive microphones which rely heavily on strong magnetic fields (which dwarf the magnetic field induced by the circuit itself). If we make the assumption (which is a valid one forribbon microphones) that the only part of the circuit which can move does so in a plane orthogonal to a constantmagnetic field and call S the apparent area of the circuit "seen" by that field, thenthe following expression for the flux enclosed by the circuit holds:
= 0 + L I + B S
The first of those three terms is an irrelevant constant and the second term is dwarved by the third. Therefore, in the main:
U = ' = B S'
Between two strong neodymium magnets (e.g.,BX044-N52) the magnetic field B can be about 1 T.
Longitudinally, a corrugated aluminum strip behaves essentially like a ribbon with a very lowYoung modulus YC (this depends on the thickness of the material and the shape of the corrugation but, paradoxically, not on its scale). Transversally, it's virtually impossible for the ribbon to bend. So, a corrugated ribbon behaves like a membrane whose mean curvature H is half the longitudinal curvature of the ribbon (as the transversal curvature is utterly negligible). The pressure difference between the two sides of the membrane is given by the Young-Laplace equation:
p+ p = 2 H = .
(2018-01-14) Signal to Noise Ratio (S/N or SNR).
(2018-01-25) Sensitivity is the ratio of voltage output to sound pressure input.
The sensitivity of a microphone is defined as the ratio of the variation in its electromotive force output (i.e., the open-circuit voltage it produces) to the corresponding variation in sound pressure input. When neither is too large, that's a constant.
That sensitivity is most commonly expressed in mV/Pa (millivolt per pascal) assuming a standard sinusoidal sound signal of 1 Pascal amplitude (94 dB SPL) at 1 kHz.
When decibels are used, the dBV/Pa scale is usually understood. Thus, the stated dB sensitivity rating is 20 timesthe decimal logarithm of the sensitivity expressed in V/Pa (which is the standardSI unit for sensitivity).
Sensitivity of 35.5 mV/Pa is -29 dB (re: 1 V at 1 Pa).
Indeed, we have: 20 log (0.0355 V/Pa) = -28.99543... dBV/Pa
A microphone is said to be loud when its sensitivity is high (the opposite of loud is soft). Normally, the louder the better, because of a lesser need for amplification (as a signal is amplified, so is the accompanying noise). However, there's such a thing as too much of a good thing: If a microphone is too loud, it may generate unexpectedly high voltages at the input of the next circuits (preamplifiers). That won't damage them but they'll saturate or clip (same thing) which will introduce unacceptable distortion.
Today, microphones are rarely designed with a sensitivity exceeding 50 mV/Pa (that's -26 dBV/Pa). The discontinued predecessor of theaforementioned BP4071 was the AT4071a which had a nominal sensitivity of 89.1 mV/Pa (that was -21 dB). This is considered way too loud by today's standards for general-purpose use (although bird lovers still like this kind of sensitivity in a directional microphone).
Warning : An older decibel scale for microphone sensitivity is still floating around which differs from the modernone by 20 db. In that obsolete scale, the aforementioned BP4071 would have been quoted as having a sensitivity of -49 dB (which could be misinterpreted as quite low).
The discrepancy comes from the former use in acoustics of the units of pressure still preferred bymany meteorologists. When meteorologists in France and elsewhere were criticized for issuing TV reportsexpressed in millibars (1 mb = 100 Pa) instead ofa proper SI unit, they didn't change their numbersbut started using the SI-equivalent hectopascal (which is correct albeit arguably somewhat weird).
In the old days, audio engineers were routinely using the microbar (0.1 Pa) as their unit of pressure (this was an alternate name for the official unit of pressurein the CGS system, namely the dyne per square centimeter). This made the volt per microbar (10 V/Pa) their unit for microphone sensitivity. Using that unit, thenumerical values of sensitivities are ten times smaller than the values in V/Pa. Expressed in decibels, they're thus 20 dB lower, as advertised!
In Numericana, microphone sensitivities are only given in mV/Pa. Not only does this avoid the aforementioned ambiguity of decibels, but it also serves as a constant reminder of what sensitivity is all about.
Electromotive force vs. measured voltage :
Microphone sensitivities are best expressed in terms of open-circuit voltages (the common name given to electromotive forces). So defined, sensitivity depends only on the microphone itself, not on whatever load it may have to drive (usually, the input impedance R of some preamplifier).
Nevertheless, some manufacturers give the actual voltage V that would be observedper unit of sound pressure into a load of specified impedance within the range they recommend (e.g., A = 1 k). That number is slightly smaller than the aforementioned intrinsic sensitivity U. The relation between the two is obtained by observing that the microphone's output current is equal tothe preamplifier's input current. Let z be the microphone's output impedance and Z be the preamp'sinput impedance:
i = U / (Z+z) = V / Z (at 1 Pa). Therefore:
U = ( 1 + z/Z ) V
For example, if a 200 microphone is said to yield 10 mV/Pa into a 1 k load, then we just quote its intrinsic sensitivity U as 12 mV/Pa.
Such a microphone would drive a 2.5 k load with
12 / (1 + 200 /2500) = 11.111 mV/Pa.
At a given audio frequency, the electromotive force and theoutput impedance of a microphone can be deduced from electrical measurements (current, voltage and phase difference between the two) under just two different load. There's no need for acoustic calibration (we do need such a calibrationto establish the sensitivity though).
The electric noise of a dynamic microphone depends entirely onthe how its impedance as a function of frequency (to that should be addedthe acoustic thermal noise at a prescribed tem[erature and pressure, which depends mostly on the size of the diaphragm).
(2018-02-05) Omnidirectional, bidirectional, cardioid, etc.
(2018-02-05) A cardioid is the sum of omnidirectional and bidirectional patterns.
Multi-pattern and variable pickup pattern:
Mixing equal parts of an omnidirectional pickup pattern and a bidirectional one (figure-8) yields a cardioid pattern. Other proportions in this type of mixing also yields the other traditional microphone pickup patterns:
Subcardioid pattern (between omnidirectional and cardioid).
Supercardioid pattern (between cardioid and figure-of-eight).
The above five patterns and the four intermediate ones between them yield a palette of nine patterns, whichare commonly available at the flip of a switch in somemulti-pattern microphones. The term hypercardioid is sometimes applied to any such mix but it's mostoften reserved to patterns with a wide cone of silence up to (butexcluding) the bidirectional figure-of-eight itself (90° angle of silence).
Variable-pattern microphones (e.g.,CAD Audio M179) even allow youthe freedom to dial anything in-between.
Note that a two-diaphragm microphone which is capable of recording at least twopickup patterns from the above standard family can also be used to reconstruct any of them in post-production. For example, if the omnidirectional signal is on theleft channel and the figure-8 bidirectional signal is on the right channel, Then, you obtain a forward cardioid by adding the two channels and a backward cardioid by subtractingthem (opamps were originally intended do perform exactly thissort of operations). This way, you can choose the pickup pattern after recording.
Any dual-diaphragm microphone could be modified into a pseudo-stereo microphone capableof recording the two separate phase-tracks just described. Two products offer this capability straight out-of-the-box:
The Lewitt LCT 640 TS microphone (TS stands for twin system) whose secondary output is on a mini-XLRconnector (sideways).
The MS("Mid Side") attachment for the 10-pin connector of Zoom recorders (H5, H6,F1, F4, F8) records separately the signals from two capsules: Forward cardioid and sideways bidirectional.
Other multiple-diaphragm configurations would provide other capabilities.
Multi-pattern dual-diaphragm microphones (data is for cardioid pattern)
(2018-05-08) Putting several very different microphone capsules in the sams housing.
Driven by professional demand, some manufacturers have put several capsulesusing different technologies behind the same grille (e.g., a condenser mic and a dynamic mic next to each other). This allows an adjustable frequency response but there are complicated phase issuesat high-frequency, which restrict such compound microphones to specialized applications (e.g.,kick drum).
Compound microphones (including more than one capsule)
(2018-01-29) Calibrated ¼'' or ½'' omnidirectional measurement microphones.
Most prosumer measuring microphones have a ¼'' capsule (6 mm diaphragm). Professionals sometimes use smaller membranes (3 mm) which are more accurate in the upper-part of the audio spectrum. They tend to prefer expensive low-noise ½'' units for general use.
Acoustic Calibrators (1 kHz, 94 dB SPL) :
By convention, absolute calibration of a sound-measuring instrumentis always done at 1000 Hz. For that purpose, standard sound sources are available which deliver precisely 94 dB SPL into a force-fit microphone port allowing cylindrical microphone heads up to 1'' in diameter (sometimes only ½''). Smaller microphones require adapters which may or may not be included with calibrating units. Below is a list of current models of such acoustical calibrators. All of these can work either at 94 db or 114 dB (the latter setting is helpful in a noisy environment).
Now, the calibrators themselves drift out of calibration and have to be recalibrated yearlyby the manufacturer. Most people will only trust Brüel &Kjær (or possibly Cirrus) for that follow-up.
Sound Meters, Measurement Microphones :
Measurement microphones are designed to be as linear as possible, They have a flat frequency response throughout the audio range anddeviations must be carefully documented (see examplebelow). Tiny diaphragms help keep resonant frequencies safely outside of the audio domain.
Many uncalibrated consumer models are just intended for the analysis of room acoustics and cannot be trusted beyond a precision of 2 dB or 3 dB. The following models are thus not recommended for scientific applications:
$299: Audix TM-1 (uncalibrated version of the Audix TM1-Plus).
A much better precision is offered at a similar cost with any of the models listed below. Each such unit comes with an individual calibration curve made with a professional instrument. The resulting on-axis frequency response is typically made availableonline (tied to the serial number of every microphone) in a digital form suitable for audio-analysis software. Sonarworks also provides an off-axis curve.
Some measurement microphones which come with individual calibration curves :
With a street price of $50 (I just got mine on sale for $40) the EMM6 is the mostaffordable of the above. Packed with each unit is a dated plot of its frequency response. The corresponding data is also available online (tied to the serial number) in the form of a tab-separated text file (ready to import into Excel or other specialized software). That file containsmeasurements at a precision of 0.1 dB for 256 frequencieswhose logarithms are evenly spaced, from 20 Hz (n = 0) to 20000 Hz (n = 255). That's to say:
fn = (20 Hz) 10 n/85 (for n between 0 and 255 = 3 x 85)
The values are given in decibels relative to the level at frequency f145 = 1016.0436 Hz which is given tersely in absolute terms (in dBV/Pa) on the first line of the data which reads, in the example of my own unit:
*1000Hz-39.6
This misleading header actually indicates that the sensitivity of this particular microphone is -39.6 dBV/Pa (i.e., about 10.47 mV/Pa) at precisely 1016.04 Hz (not 1000 Hz).
To obtain a very precise value of the sensitivity at exactly 1 kHz (which is the usual standard) we remark that 1000 Hz = fn when
n = 85 log 50 = 144.4124503685615984... = 145 0.58754963...
The data for my own unit says that the sensitivity for f144 is 0.2 dB above the level for the aforementioned ad hoc reference frequency (f145 ). Thus, the response at 1000 Hz is best obtained by linear interpolation:
Now, all of the above are based on actual voltage measurements performed by Dayton into a load of 1000 (precisely so, hopefully). As the nominal impedance of the EMM6 is 200 , its intrinsic sensitivity is obtained after a correction of 20% (i.e., 1.58 dB). Beforerounding, we obtain:
-37.899... dB/Pa or 12.7367 mV/Pa
(2018-02-09) A switchable input pad allows a microphone to record louder sounds.
Such a pad is a network of resistors placed just after the microphone capsuleto prevent the subsequent activeelectronics fromsaturating ("clipping").
(2018-02-09) Filtering out the lowest audio frequencies.
On many microphones, a switchable low cut filter is providedto get rid of the low-audio and sub-audio hum and rumble. Typically, a corner frequency of 80 Hz is used.
Most manufacturers are content with a simple first-order filter (6 dB/octave) whichprovides a modest 12 dB attenuation at 20 Hz.
Others, like Audio-Technica will do more and they should be commended for it. If you need low-cut in an urban environment, the more attenuation the better. Even in their entry-level AT2035, the low-cut filterthey provide is second-order (12 dB/octave) for a 24 dB attenuation at 20 Hz.
On Audio-Technica shotgun microphones (AT897, BP4073, BP4071) the switchable low-cut filter is third-order (18 dB per octave) and provides an attenuation of 36 dB at 20 Hz (that's 12 dB at 50 Hz).
(2017-11-22) Condenser type (varying capacitor) or dynamic type (varying inductor).
Microphones currently being produced range in price from $1.67 to thousands of dollars (the AKG C12 VR sells for &5999). Used vintage Neuman U67 tubeLDC microphones are typically sold for $9000-$16000, depending on condition. At least part of that madness is due to a nostalgia for the particular typeof distortion introduced by tube (or valve) circuits.
Designing microphones is an art form in itself. Microphones are a crucial tool for musicians and an object of worship for countless audiophiles. Just enumerating the main aspects on which that subculture is based will serve todemonstrate that we can only scratch the surface here (focusing, as usual, on nontrivial numerical aspects besides cost). All these aspects are interrelated:
Price, cost of ownership.
Options and customizability.
Look, feel and durability.
Size and weight.
Possible mounts (handheld, tabletop, lapel, stand, arm, boom).
Sensitivity at various frequencies (bandwidth & microstructure).
Impedance magnitude and phase shift (as functions of frequency).
Directivity (polar pattern) at various frequencies.
Proximity effect at various frequencies.
Noise figure, noise floor (hiss).
The previously introduced concept of sensitivity influences greatly overall noise performance because lower sensitivitydemands greater subsequent amplification, which magnifies hiss just as much as the useful signal.
The self-noise (or equivalent noise level, henceforth tabulated as hiss) of a microphone is the loudness of the signal it produces by itself in an isolated soundproof enclosure (it would be cheating to report only the electric noise of the apparatus without the microphone capsule). The same figure of merit is sometimes reported as a signal-to-noise ratio (SNR) assuming a 1 kHz sinusoidal standard soundwave of 1 Pa amplitude (94 dB SPL):
SNR = 94 dB - (self-noise, dB)
The dynamic range of a microphone is defined asthe decibel difference between the aforementioned self-noiseand the top loudness it can record, with less than 1% THD (total harmonic distortion).
The nominal output impedance is expressed in ohms (). A microphone is normally plugged into a preamplifier whose input impedance shouldn't be lower than whateveris specified by the microphone manufacturer On the other hand, it shouldn't be too high either because high impedance breeds noise. A time-honored rule of thumb is to load a microphone with five to ten times its own output impedance.
Some compact microphones sold with on-camera mounts :
(2018-02-01) Resonant frequencies and frequency-dependence of pickup patterns.
The diaphragm of a condenser microphone consists of a thin circular membrane whose rim isattached under tension to a rigid hollow cylinder. In the so-called center terminated variant, the diaphragm is also anchored by a small screw at the center, where it can neither move nor tilt... That method is used, in particular, in good ½''measurement microphones. It presents three major advantages:
The center point can be used for electrical contact.
Resonances are suppressed if the center isn't a node.
Resonances are suppressed if the gradient at the center is nonzero.
Those last two properties eliminate the lowest resonant frequencies for acircular membrane of prescribed size, areal weight and tension. That helps remove all resonant frequencies away from the audio range. However, the central contact restricts the amplitude of the diaphragm's motion at lower frequenciesand thus reduces the basic sensitivity of the microphone.
A condenser microphone is formed by the varying capacitor consisting of one such diaphragmopposite a rigid backplate (polarized by an external voltage and/or anelectret). When those two form a closed capsule, an omnidirectional pickup pattern is obtained (at least at low frequencies).
The mathematical simplicity of the above configurations makes a completetheoretical analysis possible, which may serve as a useful basis for experimental refinementsin the actual design of commercial microphones.
Another aspect amenable to pencil-and-paper analysis (barely so) isthe pickup pattern (sensitivity as a function of direction) of a large-diaphragm for a sound having a wavelength commensurate with its size (for much larger wavelengths, the pickup pattern is omnidirectional).
(2018-01-22) Quintessential capacitive microphones. Every voiceover artist has one.
Most condenser microphones use the 48 V phantom power normallyfound on XLR sockets (one more reason to get an XLR1 audio adapter, if you shoot video with a Panasonic Lumix GH5).
One popular LDC microphone is the affordable AT2020 from Audio-Technica ($99 bundle). I went instead for its big brother, the AT2035 ($149 bundle) because of a side-by-side sound comparison on YouTube.
Also, unlike the AT2020, the AT2035 has two desirable features:
Switchable 10 dB in-line attenuator ("pad") whose effect is equivalent to tripling the distance from the sound source.
Switchable second-order high-pass filter with 80 Hz corner frequency, which helps cut out hum and rumble in an urban environment. (Other makes often provide onlyfirst-order.)
The AT2035 gets rave reviews as the best in its class (I wouldn't consider a higher class for home use, following the law of diminishing returns). That microphone comes with a soft pouch and a shockmount (includinga plastic thread adapter; 5/8''-27 male to 3/8''-16 female). I got mine with a complimentary 10-ft XLR cable and Neewer®pop screen. All for $149. The shockmount by itself (AT8458) would sell for $79. (Third-party shockmounts go for $10, a short cable is about $9 and the pop shield is $7.)
The AT2035 was released in 2008. It's built around a center-terminated 24.3 mm diaphragm (0.96"). It uses back electret polarization, which helps accommodate a wide range of phantom voltages (from 11V to 52V). Some purists still scoff at this approach, compared to what they call true condenser microphones, in spite of the fact that the electret technology has been aroundfor more than 50 years and helps deliver superb performance.
To address such queasies within the Audio-Technica ladder, the AT2035 is bracketed by two condenser microphones which are purely DC-biased without electrets, the AT2020 and the AT4040 (which both demand 48V phantom power). The latter costs twice as much as the AT2035 without offering any improvement in self-noise. (Since it's 1 dB more sensitive, it's technically just 1 dB quieter.)
Audio-Technica reports that they incorporated into the AT2035 the honeycomb diaphragm design used in their own $3000 AT5040 flagship, for increased surface area and enhanced performance.
In the following table, we give a wide selection of the medium-to-large condenser microphonesavailable today. All of those are single-diaphragm microphones (we list separately dual diaphragm microphones featuring selectablepickup patterns). They're all cardioid microphones, except :
Earthworks SR40V (hypercardioid).
CAD Audio E100s, (supercardioid).
Some current LDC microphones (Data with all pads and filters disengaged.)
Because of its 4 dB sensitivity advantage, Audio-Technica's AT2035 ends up being 12 dB less noisy than the AT2020 (or 18 dB less noisy than themulti-pattern Behringer C-3). Likewise at the high-end, the AT5040 is 8 dB more sensitive and 15 dB less noisy than the AT2035. It's twice as sensitive and 4.7 dB less noisy than the Equitek E100s.
The Samson C01 mic gets mixed reviews; it's reportedly rather hissy.
(2017-11-22) Rugged inductive microphones, usually with limited bandwidth.
A moving-coil dynamic microphone functions exactly as an ordinary speaker. Actually, a moving-coil speaker can be wired to work as a dynamic microphone, albeit a lousy one. Because a dynamic microphone is a passive component, it generates no noise besides thermal Johnson-Nyquist noise.
Unlikecondenser microphones, dynamic microphones don't requireany outside polarization voltage to work. There are two very different types of dynamic microphones:
As part of an old-school PA system I purchased years ago, I got the rugged Radio-Shack 3303043 Super-cardioid Dynamic Microphone (RS catalog number 33-3043) which is a perfect voice microphone in that capacity (great proximity effect). That unit is still available new on eBay, between $25 and $50 or so (it goes for less than $20 used). It has the exact same look and feel as the legendaryShure SM58S (SM58 with a mute switch). Both feature the exact same spherical grille (51 mm diameter). The built quality is the same, except that the RadioShack body is a half-inch longer and has a black grillecoupling (which is silver on the Shure unit).
Some Dynamic Microphones (moving-coil microphones)
The 33-3043 microphone was manufactured by Shure specifically for RadioShack. So were other dynamic microphones. All were made in Mexico and nonehad any direct equivalent in the regular Shure line (they were typically looselyrelated to more expensive Shure models sporting the same grille). Examples include:
Omni Directional Microphone by Shure(Realistic33-1070).
(2018-02-04) A very special type of dynamic microphone.
The engine (or motor) of a ribbon microphoneis a very thin corrugated strip of metal (usually aluminum) which fits tightly between very strong magnets without touching them (today, neodymium magnets are used). The ribbon thus separates twosymmetrical cavities formed by the walls of the magnet. As the ribbon moves in response to sound pressure, a tiny electromotive force appears between its extremities which areconnected to the primary windings of a step-up audio transformer.
The natural acoustical symmetry of such microphones translate into a figure-8directional pattern. They pick up sound equally well from the front or the back and very little from theperpendicular directions.
Ribbon microphones include legendary lip microphones like the Coles 4104 for dramatic voice reporting in very loud environments.
Examples of Ribbon Microphones (special type of dynamic microphones)
(2018-02-02) Small-diaphragm condenser microphones with high directivity.
A shotgun microphone consists of a standard standar capsule monted at the rearof a long interference tube with a number of slots on it. On-axis sound passes through the tube unimpeded or theough the different slots in phase (constructive interference). On the other hand, destructive interference attenuates off-axis waves as they pass through the slots withdifferent phases.
Because of their natural cylindrical shape, shotgun microphones oftenfeature a compartment for a single AA battery to power them asan alternative to phantom power (units primarily intended for use with DSLR or hybrid cameras don't even allow phantom power).
The Audio-Technica models AT4071a and AT4073a are discontinued. They've been superseded by the BP4071 and BP4073, respectively.
A few comments are needed about the bottom of that table, which lists low-end consumer product, as the listed prices indicate:
The VidPro models (14-inch XM-88 and 10-inch XM-55) come with plenty of accessories (each as a 13-piece kit in a molded case). Their noise figures are undisclosed by the distributor. The audio quality is modest buteither microphone can be very cost-effective, as it can be plugged directly into the 3.5 mm socketof a DSLR (cable included) running off its own internal AA battery. They can also use XLR phantom power.
The BY-PVM1000 is consistently reported to suffer from crackling noises when operated off 48V phantom power. This problem is reported in some written reviews and can be heard even infavorable video reviews. That seems to be a design flaw present in all units (it may be caused by capacitors with borderline voltage ratings). Not recommended at all for use with 48V phantom power (and audio quality is downrated on battery power). Could be OK with 24V phantom power, who knows?
The cheapest XLR shotgun microphone, sold as Marantz SG-5B, is just adequate for experimentationsand educational projects (dissecting a microphone). It has been on sale at $16 or less. Its restricted bandwitdth and high noise make it unsuitable for any type of video production. (It's apparently not a fake; the official Marantz site does report the poor specs.)
For completenes, the Neewer bargain brand also sells short (10")and long (14.37") shotgun microphones on the cheap (for$23 and$24, respectively). They can't use phantom power and will work for up to 26 hoursoff a single AA battery.
(2017-11-01) The best way to isolate a voice from ambient sound.
It's an unavoidable part of the physics of sound that tiny microphones will produce more hiss than full-sized ones. Lavalier mics are appealing in other ways. Draw your own conclusions.
All commercially available lapel mics are condenser mics whichneed either their own battery or plug-in power from the audio socket, typically from 2 V to 10 V (more than 10 V may damage the mic and 48 V will fry it).
Properly taking sensitivities into account, the shocking truth which emerges fromthe nonexhaustive table below is that the least noisy lavalier mics are the ME2 and the Giant Squid (the latterbeing only 0.2 dB behind, which isn't significant). The MKE2, which costs three times more than the former and eight times more than the latter, is actually 2 dB worse than either! The J 044 and the HQ-S are respectively 5 dB and 10 dB worse than the ME2. (I don't have data yet for the Purple Panda and the lowly Neewer.)
Noise is only part of the whole story and the less-than-stellar performance of theexpensive MKE2 in that department is entirely due to its tiny size. The relatively low noise of the ME2 is partly due to its limited bandwidth.
Some Omni-Directional Lavalier Microphones (a.k.a. Lav mics, lapel mics)
Sennheiser's cost-no-object MKE2 is fairly bright (+4 dB at 10kHz) to compensate for thefact that it's normally worn under a shirt. It comes with several caps to adjust its frequency response.
Sennheiser's mics come with locking plugs ("EW" = "Evolution Wireless"). JK's very popular Mic-J 044 (which may well be the best value for the money) is available with many plugs to choose from (including Sennheiser's locking connector). Usually, all others only have regular TRS and/or TRRS 3.5mm audio jacks.
The Neewer 0077 microphones are extremely cheap (I just got three of them for a grand total of $4.99.) You can't buy fewer than three at a time. They are essentially disposable microphones. They are reportedly prone to failureand are supposed to produce only junk boomy sound... However, they're certainly not a total waste of money. They do sound better thanmost on-camera mics. With low expectations, I was evensurprised to find the sound rather pleasant on my initial test!
