FAQ

• Can I power a HME 26 headset from a body pack transmitter?

  The HME 26 capsule wants to see between 8 and 15 V DC to operate. The SK 100 body pack can supply 10 V. To power the HME 26 from an SK 100 body pack the cable of the HME 26 must be terminated in the standard 3.5 mm connection (ie: tip is hot and the ring and sleeve are tied together and grounded).

  NOTE: You cannot use a standard CM1 mic cable plugged into a HME 26 headset with the MZA 900 P (48v phantom power adaptor) as it does not function correctly because the MZA 900P needs to get 48v Phantom Power to function.

  
  
  
• What is the maximum SPL of a dynamic microphone?

  It is a common saying that dynamic microphones just have no maximum SPL.
  This saying is not technically exactly correct but for every day use use of dynamic microphones you will not find gain limitations. At SPL levels above 160 dB some mechanical problems might occur (for example the voice coil might crash onto the magnet) but these SPL levels are very hard to find in real world.
  Here at Sennheiser we use dynamic microphones for distortion measurements on loudspeakers at very high sound pressure levels. At Sennheiser we have measured the SPL and THD inside a large 2" driver/horn combination with a MD 421. The max SPL this combination was able to produce was 150 dB and the THD level recorded by a MD 421 was below 1% (produced by the driver not by the mic)
  So as a conclusion we can state the MD 421 has no maximum SPL limitations for practical use. However if using dynamic microphones at high SPL levels a user should be aware that the very high voltage (up to several volts) delivered by the microphone might cause problems when connected to mic preamps.