The Brüel & Kjær 4136 is a 1/4-inch externally polarized condenser microphone cartridge engineered for precision acoustic measurements across high-frequency and high-level sound fields. Designed as a pressure-type sensor, the 4136 delivers accurate response from 4 Hz to 70 kHz (± 2 dB) with open-circuit sensitivity of 1.6 mV/Pa (–56 dB re 1 V/Pa) at 250 Hz. Its compact form factor—10.5 mm height with grid—makes it ideal for applications demanding high spatial resolution or installation in confined spaces.
## Technical Specifications
• **Type:** Condenser microphone cartridge (pressure characteristic)
• **Nominal Diameter:** 1/4 inch
• **Frequency Response:** 4 Hz to 70 kHz (± 2 dB); lower limiting frequency –3 dB: 0.3–3 Hz
• **Open Circuit Sensitivity:** 1.6 mV/Pa (–56 dB re 1 V/Pa) at 250 Hz
• **Distortion Limit:** > 172 dB SPL at 3% distortion (3% at 100 Hz)
• **Thermal Noise:** 30.5 dB(A)
• **Resonance Frequency:** 70 kHz
• **Polarization:** 200 VDC external
• **Cartridge Capacitance:** 6.4 pF at 250 Hz (6.1 pF nominal)
• **Physical Height:** 10.5 mm (0.41 in) with grid; 9 mm (0.35 in) without grid
• **Preamplifier Thread:** 5.7 mm – 60 UNS
## Key Features
• Extended frequency response to 70 kHz enables measurement of high-frequency acoustic phenomena and ultrasonic components
• High distortion headroom (> 172 dB SPL) for measurements in intense sound fields without saturation
• Low thermal noise floor (30.5 dB(A)) supports precision low-level acoustic analysis
• Compact cartridge dimensions optimize spatial resolution in field measurements and tight installation geometries
## Typical Applications
• High-level and very high-frequency acoustic measurements
• Pulse and transient sound measurement
• Coupler and boundary microphone applications
• Model testing and scale acoustic environments
• Random incidence measurements
## Compatibility & Integration
The 4136 cartridge interfaces with Brüel & Kjær 1/4-inch and 1/2-inch (with adapter UA 0035) preamplifiers: Type 2633, Type 2639, Type 2645, Type 2660, Type 2669B, and Type 2669L (LEMO connector variant).
