Microphone amp

The earplug's mic amp allows you to listen to low-level signals.

With the Mode switch in Amp position, the gain of the monitor input will be set to either 20db or 40db depending on the position of DIP 1 (Amp Gain).

The earplug will also supply a 48v phantom power supply to the monitor socket. This can be enabledmomentarily with the Multiswitch for testing, or if you want a permanent supply (see Gain Raiser below)  this can be set using DIP 2 (Phantom On)

Depending on the position of DIP 4 (Onpass) this signal can be reproduced at the Sender output if required enabling the earplug to be used as a “Gain Raiser”.

Imagine the situation...

You are, once again at the end of the long microphone cable with a microphone that doesn't work. You have used the Sender section to check the Phantom power supply to the end of the cable and it's O.K. You've sent tone at line level to make sure you're on the right cable and at mic level to test the routing on the sound-desk and they're both O.K. So the microphone must be faulty.

Connect the microphone to the Monitor Input and set the mode switch to Amp.  The input now has 40db gain. If the microphone is self powered or dynamic, you will now be able to listen to its signal. If the microphone is electronic, pressing the Multi-switch will connect  48V Phantom Power. You can now listen to the output of the microphone on the loudspeaker or headphones.

(Please see the disclaimer in Monitor section!)

 

Earplug can also be used as a Gain Raiser...

Imagine the situation...

You have a mic in your rig on a long run of cable which goes close to a mains cable for some distance. When you listen to the mic at the desk, there is some mains hum being induced on the line. You can either re-route the cable further from the offending mains or connect the mic to your earplug, select Amp mode, Onpass (using DIP 4) and, if required, Phantom On (using DIP 2), set the Gain required and (20db if you expect louders signals or 40 for quieter ones) and then you will not have to amplify the signal so much at the mixing desk thus reducing the unwanted noise. There is also the option to power the earplug from an external DC source in the shape of a camera battery or mains supply so that you can leave the earplug in place.