Professional Dynamic Microphone

There's a lot of confusion out there about what makes a dynamic microphone different from a condenser. I get emails about this almost every week. The short version: dynamic mics use a moving coil attached to a diaphragm. No phantom power needed. You can drop them, use them in humid environments, point them at a 120dB guitar cabinet. They just keep working.

I want to walk through some of what I've learned over the years, including some mistakes I made early on that cost me time and money.

The Shure SM58 has been around since 1966. I checked. Fifty-seven years and they haven't changed the design much because they don't need to. Every venue I've ever worked in has at least three of these in a drawer somewhere. The SM58 handles vocals. The SM57 (same capsule, different grille) handles everything else. I've recorded snare drums, guitar amps, brass sections, and once an accordion with SM57s.

Since 1966

Shure

SM58 / SM57

The SM58 handles vocals. The SM57 (same capsule, different grille) handles everything else. I've recorded snare drums, guitar amps, brass sections, and once an accordion with SM57s.

$99 Entry Price

57 Years In Production

Universal Application

Broadcast

Electro-Voice

RE20

What you see in radio stations. The Variable-D design reduces proximity effect, meaning broadcasters can move around without voice going boomy then thin.

$449 Price (2019)

1.6 lbs Weight

Podcast Standard

Shure

SM7B

Became the podcast standard around 2015-2016. Needs a lot of gain—60dB or more for quiet voices. Most budget interfaces can't deliver that without adding noise.

$350+ Price Range

60dB+ Gain Needed

The Electro-Voice RE20 is what you see in radio stations. There's a reason for that. The Variable-D design reduces proximity effect, which means broadcasters can move around a bit without their voice going all boomy and then thin. I bought one in 2019 for $449. It sat in my closet for eight months because I didn't have a good enough preamp to drive it properly. More on that later.

The Shure SM7B became the podcast standard somewhere around 2015 or 2016. I remember when they were $350 and in stock everywhere. Try finding one at list price in 2020. The SM7B needs a lot of gain. I mean a lot. We're talking 60dB or more for quiet voices. Most budget interfaces can't deliver that without adding noise.

Dynamic microphones have lower output than condensers. The SM7B outputs around 1.12mV/Pa. A typical large diaphragm condenser puts out 20-30mV/Pa. That's a significant difference when your audio interface only has 56dB of clean gain.

I ran my SM7B into a Focusrite Scarlett 2i2 for about three months. The noise floor was unacceptable. I could hear the hiss in every recording. I tried a Cloudlifter CL-1, which is an inline preamp that gives you an extra 25dB of clean gain using phantom power (the Cloudlifter uses the phantom power, not the dynamic mic). That fixed the problem. Cost me another $150.

Some people buy a dedicated preamp instead. The Triton Audio FetHead does the same thing as the Cloudlifter for less money. I haven't used one personally so I can't comment on the sound quality.

Most dynamic microphones are cardioid. They pick up sound from the front and reject sound from the sides and rear. This is useful in live settings where you have monitor speakers blasting at the performer. It's useful in untreated rooms where you don't want to capture reflections off the walls behind you.

Cardioid pattern microphones excel at rejecting off-axis sound in untreated spaces POLAR PATTERN

The Electro-Voice RE20 is technically cardioid but the pickup pattern is tighter than most. It really rejects off-axis sound. I recorded two people having a conversation once, each with an RE20, positioned about three feet apart and angled away from each other. Almost no bleed between the mics. Made editing much easier.

Some dynamic mics offer different patterns. The Shure SM7B has a switch on the back for presence boost and bass rolloff. Not a pattern switch, but worth knowing about.

I dropped an SM58 off a stage once. About four feet onto concrete. Picked it up, checked for dents, plugged it back in. Worked fine. I've seen SM58s that have been in service for 20+ years with visible rust on the grille. Still functional.

Cheaper dynamic mics are hit or miss. I bought a three-pack of Behringer XM8500s for a community theater project years ago. Two of them still work after heavy use. One developed a crackling sound after six months. At $20 each I didn't complain.

Dynamic microphones generally don't capture the highest frequencies as well as condensers. The SM58 rolls off pretty hard above 15kHz. For vocals, this often doesn't matter. The fundamental frequencies of the human voice sit well below that range.

The presence peak matters more in practice. The SM58 has a boost around 5kHz that helps vocals cut through a mix. The SM7B has a flatter response overall but you can engage the presence switch if you want some of that bite.

For recording acoustic instruments with a lot of high frequency detail (violin, acoustic guitar, cymbals) I usually reach for a condenser. Dynamic mics work but the recordings sound different. Not worse, necessarily. Different. I tracked an entire folk album with SM57s in 2017 and the artist loved the slightly darker tone. Said it sounded vintage.

My main vocal mic for the past two years has been the Shure SM7B. I run it through a Golden Age Project Pre-73 MKIII (a Neve 1073 clone) with a Cloudlifter in between. This is probably overkill for YouTube videos and podcast recordings but I already owned the preamp from a previous project.

Dynamic microphones are good candidates for secondhand purchase. The construction is simple and robust. There's not much that can go wrong internally. Check for dents in the grille (can affect sound), damage to the XLR connector, and any rattling sounds when you shake the mic gently (loose parts inside).

I've bought maybe eight or nine dynamic mics used over the years. Only one was a dud, a Sennheiser e835 that had intermittent output. The seller refunded me.

Condensers I'm more cautious about buying used. The capsules are more delicate and damage isn't always visible.