SM57 vs SM58

The internet's most-asked microphone question has a punchline: they are very nearly the same microphone. Both Shure workhorses are built around the same Unidyne III cartridge; the SM57 (1965) wears a flat grille that lets the capsule get close to loud sources, and the SM58 (1966) wears a ball grille with a built-in pop filter that holds a singer's plosives at bay. Nearly everything that differs between them follows from those two pieces of metal mesh.

Short answer: SM58 for live vocals, SM57 for instruments, and if you can only buy one microphone for general work, the 57 is the marginally more flexible tool while the 58 is the better companion if you sing. Now the useful details.

What Actually Differs

The grille geometry changes two things that matter. Working distance: the 57's flat grille puts the diaphragm closer to whatever it faces, which buys more level and more proximity-effect bass on snares and guitar cabinets — the microphones lesson explains why centimetres matter that much. Plosive handling: the 58's ball contains foam that turns a singer's p and b blasts into non-events; sing close into a 57 and those blasts arrive raw. The frequency responses differ measurably but modestly — the 57 carries a touch more upper-midrange edge, the 58's grille softens the same region slightly — and in a blind test on a loud stage almost nobody reliably tells them apart on the same source.

Under the grilles: same cartridge family, same cardioid pattern, same indestructibility, same low output that the gain-staging lesson reminds you any modern preamp handles fine.

The Questions People Actually Search

• SM57 or SM58 for vocals? Live: the 58, no contest — the pop filtering and the shape a singer's hand expects are the whole design. Studio: either works as a character choice, and the punk tradition of 57 vocals is real, but if a vocal mic budget exists at all, the SM7B page explains where Shure's own money goes.
• For recording vocals at home? Neither is the obvious first pick — a 57 with a cheap external pop filter is the classic budget move and genuinely fine, but the dynamic-versus-condenser question matters more than the 57/58 one; the Dynamic vs Condenser Microphones page is the decision that actually changes your recordings.
• For acoustic guitar? The 57 of the two — but this is small-diaphragm condenser territory, and both Shures are the compromise option, not the recommendation.
• Frequency response? Published curves differ by a few decibels in the presence region and grille resonance; real-world placement differences dwarf the printed difference. Do not buy on the graphs here — the specs lesson explains what such graphs omit anyway.

The Honest Recommendation

A band buying its first mics buys both and stops thinking about it — the two-57s-and-a-58 starter locker from the SM57 review remains correct. A singer buys the 58. A home recordist mic'ing amps, drums and occasional vocals buys the 57 plus a pop filter. Nobody in any of those scenarios has made a mistake, which is the deeply unsatisfying truth behind the internet's favourite mic debate: this is the lowest-stakes decision in audio, argued with the highest word count.

Worth Knowing on the Way Out

• Same engine, different grilles — the ball's pop filter and the flat grille's closeness are the real differences.
• 58 sings, 57 gets close — the design intents; both survive being wrong about it.
• The response difference is smaller than a placement difference — move either mic two centimetres and you've out-EQ'd the comparison.
• The bigger question is dynamic versus condenser — that page changes recordings; this one changes little.
• Buy on role, not on reviews — singer 58, instruments 57, band both, regrets none.