mx10: the classic danfield audio mic pre
The Danfield MX10 Microphone Amplifier is a very high quality mono unit, specially designed for ultra low noise recordings. It has gained wide acceptance since the first versions were released over 15 years ago, and is well known as the portable mic preamplifier of choice when an engineer has to go 'remote' - put it your computer bag with a cable and you are ready for the road...
On the front, the balanced Mic Input XLR connector is located along with the Phantom Power On/Off Switch. A yellow LED indicates 48V Phantom Power is present.
The red LED monitors clipping (O/L - overload) in the gain stage, and will illuminate at levels 6 dB below the actual clipping point. The gain is adjusted on the 12 step gain swit ch, giving a range from +9 dB to +73 dB. Trim controls the output stage and is adjustable +/- 5 dB.
Balanced output and mains power connection are placed on the rear of the MX 10.
The basic principle in this microphone amplifier is to treat the sensitive microphone signal in the best possible way from the very beginning. Therefore, a transformer input stage is chosen because of its perfect common mode rejection performance - which simply means that it perfectly 'sorts out' all the signals not actually coming from the original microphone electrical pulses.
A very useful side benefit of the MX10 is the low output impedance of the system. This means that the unit is capable of driving multiple parallel receiving inputs, (etc. Multitrack inputs or Desk inputs), allowing you to avoid time consuming cross patching.
Note:- the MX10 contains fixed High & Lowpass filters, calibrated to deliver very clean and smooth audio transfer - without sub frequencies and with no HF interference. The filter tilt is set to 12 dB/ Oct. - and cannot be disconnected.
The output stages are electronically balanced, but perform like a transformer in order to match the gain structure. In true balanced environments no further precautions are necessary.