Shure SM58 Review: The One Number Almost Nobody Publishes

+ 1

The verdict: ordinary numbers, one uncommon one

Sensitivity at the median of its class, weight at the median of its class, a frequency range published without a tolerance like everyone else's. On the comparable figures this microphone is unremarkable, but nothing on the listing suggests otherwise.

Then there's the number almost nobody prints: how much quieter the microphone gets when sound arrives from the side and from behind, 10 dB down at 120° and 20 dB down at 180°. Eleven of the 72 microphones in our set have that figure on their listings at all. On a stage with a monitor wedge pointing at the grille, it's the only specification that describes what the microphone is for.

Whose figure it is turns out to be a separate question, and it's answered below.

What it is

A handheld dynamic cardioid microphone for a voice at close range. Nothing inside it draws current, but nothing on it can be switched. Neither can a Sennheiser e835 at $99.95 unless the box says e 835-S.

Dynamic means sound moves a coil in a magnetic field to make the signal. Nothing needs power, nothing is damaged by loud sound, and humidity doesn't matter. The trade, though, is output, which is why the numbers below sit where they do.

Cardioid describes what it hears: most from the front, progressively less from the sides, least from directly behind. Every directional microphone claims this. The SM58, though, is unusual in having a listing that says by how much.

Handheld is what the listing calls it, and the dimensions say the same thing: 162 mm long, 51 mm across the grille, 327 g. That's a size and a mass meant for a fist rather than a stand, and everything else about the design follows from being held.

A steel grille on a grey body

A grey barrel with a spherical grille, 162 mm long and 51 mm across the ball. Here the listing gives no controls of any kind: nothing on it switches, adjusts or lights up. The thread is 5/8"-27 with a 3/8"-16 adapter in the box, which is the pair of sizes stands come in.

What 165 owners report

There isn't one single-star rating among the 165. Across the 38 products in our set with at least a hundred ratings, six have an empty one-star column, and two of those six are this microphone and its instrument sibling.

Shure's own store shows a larger sample of the same shape: 4.9 across 348 ratings, more than twice the dealer's count. The individual reviews say less about sound than the average implies. "I've tried a number of other microphones a few less expensive ones, and a few others that were more expensive. This outperforms everything I've tried," reads a five-star entry from 30 June 2026, and though it names no figure at all. Two independent populations landing on the same average is worth more than either on its own, and it's the rarer outcome in this collection, where the maker's page usually carries a handful of promotional reviews and a perfect score.

A rating shaped like this says less than it looks like it does, and the opposite shape says more. A $109 microphone that needs no power and has nothing to fail is a hard thing to be disappointed by, and nobody returns one because the app is bad. The absence of complaints is real, but it's evidence about the category as much as about the model.

What the numbers say

The comparison below is with the other dynamic microphones we have collected, all of them converted to one unit before anything was ranked.

Sensitivity 1.59 mV/Pa, seventh of seventeen

Sensitivity says how much signal comes out for a given amount of sound going in. Because manufacturers publish it in at least four notations, everything here is converted to millivolts per pascal first, and three dynamics that quote a bare decibel figure with no reference named are left out rather than guessed at.

At 1.59 the SM58 sits seventh of seventeen from the bottom. In practice that means a preamp with 50–60 dB of gain drives it comfortably, which every interface has. It isn't the demanding load that some dynamic microphones are.

Off-axis rejection, the figure that matters live

When a source sits behind the microphone, twenty decibels of rejection means it arrives a tenth as loud in pressure terms as the same source in front. That's the number that decides whether a stage monitor pointed at the singer causes feedback or doesn't.

The table comes from the dealer, not from Shure. Shure's user guide for this model states that the pattern rejects off-axis sound and advises putting monitors directly behind the microphone, but gives no figure at any angle. Nor does its product page carry a specification block at all. Where the dealer's three numbers originate isn't visible from here, and Shure's own specification sheet could not be checked because the host serving it refuses automated requests.

That doesn't make the numbers wrong, but it does change what they are evidence of. Eleven microphones out of the 82 in our set have these angles on their listings. That's not a claim that the other 67 are worse, and it isn't a claim about which manufacturers measure carefully. It's a claim about which retail pages carry a field, which is a different thing entirely and the only thing a comparison built from listings can honestly rank.

Among the eleven that do, the SM58's 20 dB at the rear is fourth, behind a Neumann condenser at more than 25 dB and a RODE shotgun at 24. Both cost several times as much, though, and neither is meant to be held. Of the microphones in that list a singer could actually take on stage, nothing rejects more from behind.

50 Hz to 15 kHz, and what the sibling publishes

The range comes with no tolerance figure, so it won't stand beside another manufacturer's. Within Shure's own line, however, it's still informative: the SM57, the instrument model Shure sells alongside it, publishes 40 Hz to 15 kHz. Ten hertz lower at the bottom, from the microphone sold for instruments rather than voices.

Unless you know how far the output was allowed to fall, neither number can be checked, and Shure doesn't say. A number that cannot be checked ranks nothing.

What you give up at $109

No pad, no low-cut filter, no switches of any kind. Nothing to set means nothing to set wrong, but also nothing to save you: a source too loud or too close is fixed by moving it, not by the microphone.

Maximum SPL is not published, though for a dynamic capsule that's less alarming than it sounds, because there's no electronics to overload. It's still another figure that cannot go into a comparison.

Once it's in the hand, 327 grams is middling for the class, and that weight stays there for the length of a set.

Right for a hand and a stage, wrong for a quiet room

Close range in a noisy room is the entire design brief: a stage, a rehearsal space, anywhere with a monitor pointed back at you. So the rear rejection is the reason, and it's the one number here that is both published and comparable.

A poor buy for a treated room where nothing else is making noise. There the rejection buys nothing, and a condenser will capture detail this capsule was never built to.

Price and specifications

Sources

1. Shure SM58-LC Cardioid Dynamic Microphone, product listing at B&H Photo Video: price, owner rating and the star distribution above.
2. The product markup on that same listing: sensitivity, off-axis rejection, frequency response, dimensions, weight and mounting thread.
3. Medians, positions and the count of microphones publishing off-axis figures come from listings of 200 audio products collected the same way. How those are converted and compared.

Listings were open on 18 August 2026; what they showed that day is what the numbers report.

What we did not do

This microphone has never been in our hands, and the rejection figures above are Shure's, not ours. What we can check is who else publishes them, and that is what the comparison here does.