Shure SM4-K Cardioid Condenser Recording Microphone

The Shure SM4-K is a side-address cardioid condenser microphone built for home recording, vocal production, streaming, and instrument capture. Its XLR output and externally biased condenser design make it a fit for users working with an audio interface or mixer rather than a USB-only recording setup. The microphone is designed to capture focused sound while reducing pickup from the rear and sides.

A 1-inch brass dual-diaphragm capsule provides controlled low frequencies and detailed high-frequency reproduction across a 20 Hz to 20 kHz response range. Its broad working area helps reduce excessive proximity effect during close vocal recording. This makes the SM4-K well suited to vocals, speech, acoustic instruments, amplifiers, horns, and drums.

The fixed cardioid pattern focuses on the source in front of the microphone and helps reduce unwanted room sound and off-axis distractions. Shure rates the SM4 for a maximum SPL of 140 dB at 1 kHz with 1% THD into a 1 kOhm load, allowing it to handle louder sources without requiring a separate pad setting. A 79 dB signal-to-noise ratio and 15 dB SPL A-weighted self-noise support clean recording work.

Shure's patent-pending Interference Shielding Technology is designed to reduce RF noise from nearby phones, laptops, Wi-Fi routers, and other wireless devices. The design combines an integrated pop filter with a woven mesh Faraday cage around the capsule. This helps keep plosives, interference, and unwanted recording artifacts under control before processing.

The SM4-K is the standard microphone package, including a swivel-mount microphone clamp, brass stand adapter, and zippered pouch. It connects through a standard three-pin XLR connection and requires +48 V phantom power from a compatible interface or mixer. Users who need suspension isolation and an external magnetic pop filter can add compatible Shure accessories or choose the separate SM4-K-KIT package.

Key Features

• 1-Inch Brass Capsule: Dual diaphragms capture controlled lows and detailed highs.
• Cardioid Pickup Pattern: Focuses on the source while reducing off-axis sound.
• High SPL Handling: Records loud instruments up to 140 dB SPL.
• RF Interference Shielding: Helps reduce noise from nearby wireless devices.
• Integrated Pop Filter: Helps control plosives and low-frequency rumble.
• XLR Studio Connection: Works with compatible interfaces and mixers using phantom power.

Design & Installation

The SM4-K uses a rugged die-cast zinc housing with all-metal construction and a low-profile black finish. At 463 g, it has the substantial feel of a studio condenser microphone while remaining practical for stand or boom-arm mounting. Its side-address format places the front logo toward the recording source.

Mount the microphone in the included A4M swivel-mount clamp, attach it to a compatible microphone stand, and use the supplied brass adapter when mounting to a 3/8-inch stand. Connect a three-pin XLR cable to an audio interface or mixer, then enable +48 V phantom power before recording. For vocals, position the source in front of the logo; use a separate external pop filter if additional plosive control is desired.