What is the Difference Between a Vocal and Instrument Mic? And Can You Use One in Place of the Other?

Although they may look similar, not all microphones are created equal. Similar to choosing a particular guitar or amplifier, your choice in microphone is often a crucial factor in the overall sound. However, microphones are generally much simpler pieces of gear. Across all their different forms, their construction and function remain the same: to pick up sound in the air and convert it to an electrical signal.

A common question among musicians is whether an instrument mic can be used in place of a vocal mic, and vice versa. This question is similar to whether or not a particular guitar can be used for a certain genre; it’s all a matter of preference, and requires experimentation. Simply because you’re recording vocals doesn’t mean you need to use a vocal mic. Just like with any other audio equipment, it’s important that you use your ears to determine if your tools are right for the application.

Here are a few simple things to look for to see if a particular microphone is the right fit: 

1. Frequency range: microphones are engineered to emphasize certain frequencies. Vocal microphones, for instance, generally have more treble response for increased intelligibility and clarity, which can be quite important in vocal performances or public speeches when the performer needs to be heard clearly and distinctly.

Instrument mics tend to be used with a wider range of instruments, from kick drums to bass and guitar, so they often provide a wider frequency range. For example, an instrument mic’s frequency response is usually around 40Hz to 15kHz, which can accommodate the low E string of a bass guitar, which is 41Hz. This is not to say that a vocal microphone that has a range of 50Hz- 15kHz will not pick up a low E string at all; it will, but it’s not quite optimized in the way an instrument mic with proper specs would be. While there are no hard and fast rules, choosing a microphone with the proper frequency response can be extremely beneficial.

Carvin Audio’s M68 vocal microphone has a full frequency response of 50Hz to 15KHz, which allows it to faithfully capture the full range of the vocal spectrum. 

2. Type/voice of instrument: Let’s say you want to mic up an electric guitar amp for a live show. Using a vocal mic that accentuates treble might not be the optimal choice, since an electric guitar naturally has a lot of mids and highs. While it isn’t necessarily a bad thing, using a microphone and instrument that are voiced for a lot of the same pronounced frequencies can make for too much of a good thing. Overemphasis in a particular frequency range can be a show stopper, and will require extra effort from the mixing board to remove. In instances like this, it helps to use the right tool from the get-go.

3.  Physical construction: While we mentioned that the microphones are fairly simple devices, some come equipped with extra features that make them better suited for certain purposes. Some microphones, for instance, are shock-mounted to reduce handling noise, and others, like the M68, have a built-in spherical pop filter which make them great for eliminating certain breath sounds on vocals.

Microphone size is also a factor, as obviously it can be hard to sing and move freely around the stage holding a microphone that is made for the studio.

What are your preferred mics for vocals and instruments? Have you ever used one in place of the other? Sound off in the comments below.

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