What it is and what it was built for
A dynamic supercardioid microphone built for live vocal use. Introduced in 1996 as a redesign of the Beta 58. Part of Shure’s Beta Series, launched in 1989.
The original Beta 58 came as the Beta 58C with a chrome grill or the Beta 58M with a matte grill. The chrome version was eventually discontinued, the matte one became simply the Beta 58, and that was in turn discontinued and replaced by the Beta 58A. The 58A won a TEC Award in 1996 for outstanding microphone technology.
How it works, in terms a player would use
It is a dynamic supercardioid microphone. It rejects sound from the sides. It attenuates low frequencies below 500 Hz to counter proximity effect. It boosts presence at 4 kHz and 10 kHz. It uses an output transformer. It has no hum-bucking coil.
The 1996 change was a completely new cartridge, intended to match the old one in polar pattern, output level and frequency response while sounding slightly different. Shure’s own website says that removing the hum-bucking coil and adding an output transformer are the two major differences from the Beta 58. The stated frequency response runs from 50 to 16,000 Hz.
What it does better than anything else
It isolates vocals in loud environments better than most dynamic mics. Its supercardioid pattern rejects side-stage bleed more tightly than cardioid SM58s. Its neodymium magnet gives higher output than older SM-series designs.
The shape and intended use resemble the popular SM58, but the Beta series uses a different capsule and a different transformer, so the Beta 58A has little in common with it.
What it does badly
It rolls off below 500 Hz. It cannot reproduce deep bass or full-range acoustic instruments cleanly. Its presence peaks fatigue some voices over long sets. It offers no pattern switching or pad.
What people made with it
Live vocal performances on stages worldwide. No specific recordings, artists, venues or releases are named in the sources.
The maker behind it is a Chicago company founded by Sidney N. Shure in 1925 to sell radio parts kits. Its Model 55 Unidyne arrived in 1939, and its 1959 Unidyne III-based 545 was the predecessor to the SM57.
Who should use it, and who should not
Front-of-house engineers and touring vocalists who need consistent rejection and high-SPL handling. Not studio engineers seeking transparency, or podcasters needing low-end warmth.
Is it worth your time
Yes — if you need a live vocal mic that cuts through stage noise without feedback. No — if you need extended low-end, flat response, or studio-grade neutrality.
