Audio-Technica BP350ST-UB MS Stereo Clip-On Cardioid Condenser Boundary Microphone

Audio-Technica BP350ST-UB MS Stereo Microphone

The Audio-Technica BP350ST-UB is a professional MS stereo microphone engineered for broadcast, production, and field recording applications. Designed for reliable stereo capture in demanding environments, this compact microphone system uses independent cardioid and figure-of-eight condenser elements in a mid-side configuration, allowing users to record crisp, clear, and well-balanced stereo sound. Its small-format design makes it especially useful for discreet placement in sports broadcasting, press conferences, theater productions, studio work, documentary filmmaking, and fixed indoor or outdoor recording setups.

The BP350ST-UB gives audio professionals flexible stereo control with switch-selectable internal matrixing. Users can choose between wide left-right stereo, narrow left-right stereo, or discrete mid-side output for later manipulation in postproduction. This mid-side design is especially valuable when editing dialogue, ambience, and live production audio because it helps maintain natural stereo depth while preserving strong mono compatibility. The two-mics-in-one configuration also helps reduce common stereo miking issues such as time alignment problems and comb filtering.

For versatile mounting, the microphone element can be used with the included low-profile boundary housing or the included 5" gooseneck with clip-on mount. The boundary housing features a snap-on grille for easy access to the microphone and a magnetized base plate for mounting on metal surfaces, along with screw-mounting holes for more permanent placement. The AT8491UC universal clip-on mount includes a 1/4"-20 thread for tripod or device mounting, while the microphone is also compatible with ATM350a mounts and mounting systems available separately.

The included AT8547 power module provides mode switching and an 80 Hz high-pass filter to help reduce unwanted ambient noise. The microphone includes a 25' permanently attached cable that connects to the power module through a TA5F connector, plus a 1.2' TA5F to dual-XLR3-M stereo output cable for connection to traditional microphone preamplifiers with phantom power. Compact, lightweight, and built for professional workflows, the BP350ST-UB is a highly flexible stereo microphone solution for broadcast, video production, and field recording.

Key Features

• Small-format stereo microphone designed for broadcast, production, and field recording
• MS mid-side capsule configuration with independent cardioid and figure-of-eight condenser elements
• Ideal for sporting events, press conferences, theater, studio productions, and documentary films
• Switch-selectable internally matrixed stereo modes including wide, narrow, and mid-side output
• Natural stereo response with excellent channel separation, even at high SPL levels
• Compact microphone body based on the popular ATM350a instrument microphone design
• Includes low-profile boundary housing and 5" gooseneck with clip-on mount
• Boundary housing includes magnetized backing and screw-mounting holes for flexible placement
• AT8491UC universal clip-on mount supports spring-clip mounting or 1/4"-20 thread mounting
• AT8547 in-line power module includes stereo mode selection and switchable 80 Hz high-pass filter
• Compatible with all ATM350a mounts and mounting systems available separately
• Includes stereo output cable, foam windscreen, and hard shell carrying case

Technical Specifications

Microphone

Microphone Type: Boundary / Broadcast Array / Gooseneck (Speech/Non-Instrument)
Element Type: 2x Condenser; 1x Condenser (Cardioid); 1x Condenser (Bidirectional)
Element: Fixed-charge back plate, permanently polarized condenser
Polar Pattern: Cardioid / Figure-8
Sound Field: Stereo (Mid/Side Configuration)
Orientation: End Address
Circuitry: Solid-State

Controls & Filtering

Controls: Low Cut/HPF, Mode
Switches: Stereo mode selection (MS, LR-W, LR-N), Flat, Low Cut
Filter & EQ: High-Cut Filter: 80 Hz, 18 dB/Octave
Low Frequency Roll-Off: 80 Hz, 18 dB/Octave

Performance

Frequency Response: 40 Hz to 20 kHz
Maximum SPL: 148 dB (1 kHz at 1% THD, Mid Channel); 149.5 dB (1 kHz at 1% THD, Side Channel)
Dynamic Range: 126 dB (1 kHz at Max SPL, Mid Channel); 125.5 dB (1 kHz at Max SPL, Side Channel)
Equivalent Noise Level: 72 dB (1 kHz at 1 Pa, A-Weighted, Mid Channel); 70 dB (1 kHz at 1 Pa, A-Weighted, Side Channel); 69 dB (1 kHz at 1 Pa, A-Weighted, Left and Right)
Open Circuit Sensitivity: MID: -33.5 dB (21.1 mV) (0 dB = 1 V/Pa, 1 kHz); SIDE: -35 dB (17.8 mV) (0 dB = 1 V/Pa, 1 kHz); L/R: -39.5 dB (10.6 mV) (0 dB = 1 V/Pa, 1 kHz)
Impedance: 50 Ohms
Signal-to-Noise Ratio: MID: 72 dB (1 kHz at 1 Pa, A-weighted); SIDE: 70 dB (1 kHz at 1 Pa, A-weighted); L/R: 69 dB (1 kHz at 1 Pa, A-weighted)

Connectivity

Analog Output Connector: 1x TB5M/Mini-XLR 5-Pin Male (on Detachable Cable); 2x XLR 3-Pin Male (on Included Cable)
Output Connector: Power Module: 5-pin Mini XLR-M Type; Microphone: 5-pin Mini XLR-F Type
Inputs: 1x XLR 5-Pin Female (on Power Supply)
Cable Length: 25' (Control to Output); 1.2' (Mic to Control)
Cable: Main unit cable: 25'; Microphone cable: 1.2'

Power

Power Sources: Phantom Power
Operating Voltage: 48 V Phantom Power
Phantom Power Requirements: 48 V DC, 8.2 mA (both channels total)

Physical

Color: Black
Mounting Thread Size: 1/4"-20 Female
Dimensions: 0.5" diameter x 1.5" L (Microphone); 0.83" diameter x 1.1" W x 4.9" L (Power Module)
Weight: 0.6 oz (Microphone); 1.7 oz (Power Supply); 3.1 oz (Boundary Housing)

Environmental

Operating Temperature Range: 14°F to 140°F
Storage Temperature Range: -4°F to 140°F, 10% to 90% RH without condensation

Compatibility

Mount Compatibility: Compatible with all ATM350a mounts and mounting systems available separately
Optional Interchangeable Elements: UE-H Hypercardioid; UE-UL Line + Gradient
Optional Polar Pattern Change: Polar pattern can be changed to hypercardioid with the optional UE-H element or to line-cardioid with the optional UE-UL element and AT8180 windscreen

What’s Included

• Audio-Technica BP350ST-UB MS Stereo Microphone
• AT8547 power module
• AT8494 boundary housing
• AT8490 standard 5" gooseneck
• AT8491UC universal mount
• 1.2' microphone cable
• TA5F to dual-XLR3-M stereo output cable
• AT8418 foam windscreen
• Hard shell carry case