Headphones
HME 27 
Transducer principle
• dynamic, closed
 
Ear coupling
• circumaural
 
Frequency response
• 8 Hz to 18 kHz
 
Impedance
• 64 Ω
 
Load capacity
• 500 mW
 
Sensitivity
• 112 dB SPL/1 V rms/1 kHz (ActiveGard™ switched off)
 
Maximum sound pressure level
• ActiveGard™ switched off: 128 dB SPL @ 1 kHz
• ActiveGard™ switched on: 110 dB SPL @ 1 kHz
 
Ambient noise reduction
• Max. 32 dB (passive, ANR switched off)
 
Total harmonic distortion (THD)
• < 0.1% @ 1 kHz, 100 dB SPL
 
Contact pressure
• approx. 3.3 N
 
HMD 27 
Transducer principle
• dynamic, closed
 
Ear coupling
• circumaural
 
Frequency response
• 8 Hz to 18 kHz
 
Impedance
• 64 Ω
 
Load capacity
• 500 mW
 
Sensitivity
• 112 dB SPL/1 V rms/1 kHz (ActiveGard™ switched off)
 
Maximum sound pressure level
• ActiveGard™ switched off: 128 dB SPL @ 1 kHz
• ActiveGard™ switched on: 110 dB SPL @ 1 kHz
 
Ambient noise reduction
• Max. 32 dB (passive, ANR switched off)
 
Total harmonic distortion (THD)
• < 0.1% @ 1 kHz, 100 dB SPL
 
Contact pressure
• approx. 3.3 N
 
HMDC 27 
Transducer principle
• dynamic, closed
 
Ear coupling
• circumaural
 
Frequency response
• 8 Hz to 18 kHz
 
Impedance
• 600 Ω (ANR switched on)
• 200 Ω (ANR switched off)
 
Load capacity
• 500 mW
 
Sensitivity
• 112 dB SPL/1 V rms/1 kHz (ANR switched on, ActiveGard™ switched off)
• 107 dB SPL/1 V rms/1 kHz (ANR switched off, ActiveGard™ switched on/off)
 
Maximum sound pressure level
• 115 dB SPL @ 1 kHz (ActiveGard™ switched off, ANR switched on)
• 128 dB SPL @ 1 kHz (ActiveGard™ switched off, ANR switched off)
• 110 dB SPL @ 1 kHz (ActiveGard™ switched on, ANR switched on/off)
 
Ambient noise reduction
• Max. 32 dB (passive / ANR switched off)
• Additional max. 15 dB (ANR switched on)
 
Total harmonic distortion (THD)
• < 0.1% @ 1 kHz, 100 dB SPL
 
Supply voltage
• Phantom powering P12–P48, 12 V to 48 V, ≤ 10 mA
 
Contact pressure
• approx. 3.3 N