Question: How do you decide which microphone to use for a specific application?
Answer: At the end of the day, microphone selection should be done by listening and analyzing how something sounds. Sound is subjective and what “sounds good” to one person may not be the best choice for another. The sound you are after may have certain characteristics that a particular microphone is better at capturing than another mic is. You can use the specifications of a microphone to begin your microphone selection process, then narrow down further by listening.
The human voice is a complex instrument. So it can be challenging to select the proper microphone that captures the voice’s nuances; a slight difference in a microphone specification can alter the character of the captured audio. Large-diaphragm microphones such as the AT5047 and the AT2035 offer a greater signal-to-noise ratio compared to small-diaphragm microphones, which offer quicker transient response. Analyzing a microphone’s sensitivity and frequency response will also help in determining which microphone to use for a certain application. There are a variety of characteristics each microphone has, and many engineers can rattle off specifications and sound adjectives for microphones they have used. This is a tool that seasoned engineers have in their brains that can help cut down on setup time and the microphone selection process.
We could spend a long time with any specific application you might think of, but let’s look at just two examples.
The first example is choosing a microphone for a conga drum. Some questions we would ask are, “How are we using the microphone?” “What is the tonality of the instrument we want to capture?” And, “What microphone characteristics may enhance the sound we are looking to capture?” A large-diaphragm microphone like the AE3000 will pick up the rich tone of a conga in a studio setting, but in a live performance, a microphone like the ATM350a will give us a better (and quicker) mounting option to the drum, a smaller footprint for aiming the microphone element to the sweet spot, and a smaller diaphragm for quicker transient pickup. The frequency range and tonality of the drum may also lead us towards a particular microphone. If the drum is larger and has a broader, lower tonality, a microphone such as the ATM250 may enhance the richness of the sound, whereas if the drum is smaller, the frequency response of an AE3000 may be better suited to what the drum produces.
The second example is a bass vocalist in a vocal quartet. Most bass vocalists end up choosing the AE5400 microphone over the AE6100 for reasons that become clear when we examine the specifications of the two mics. The AE6100 starts to drop off the lower frequencies beginning around 125 Hz, whereas the AE5400 is pretty flat down to about 80 Hz and even has a slight bump around 50 MHz. This may be excited when the vocalist uses the proximity effect to their favor to fill out the sound running through the subwoofers in the sound system. The AE5400 presents the low richness of the vocalist’s voice but also has a tailored top end that keeps the vocals from getting a “muddy” sound. The AE6100 has a full top end and a nice gradual bump beginning just over 1.2 kHz, which often allows a vocalist to cut through the mix of a full band. Both are great microphones used by a variety of multiplatinum-selling artists, but one may work better with a certain vocalist’s voice.
A lot of microphone selection is trial and error, but always remember that the final judge is your ears. Sound is subjective and there is no one “right” answer when it comes to sound and selecting a microphone. Contact the Audio-Technica Audio Solutions Department to further discuss which microphone models we would recommend for a particular application.