Aphex 188 Eight Channel Mic Preamp - Manual (Page 4)

188
Why remote controlled preamplifiers?
Locating the mic preamplifier as close as possible to the microphone eliminates the long cable runs at mic level.
Induced noise would be amplified. In addition, capacitance and resistance in that long cable run would af fect
the performance of the microphone.
Transformer splitters are only effective in isolating ground. The impedance from all the preamplifiers connected
to the system as well as the cabling combine to load down the output of the microphone. For example- most
microphones are designed to drive between 1200 and 1500Ω loads. If a microphone is connected to three pre -
amplifiers, the input impedance is 500Ω. The sonic effects are reduced frequency and transient response, and
higher noise. The increase in audio quality when the microphone is driving an ideal load is dramatic. The 188
acts like an active splitter with one analog and two digital outputs..
Once you have line level signal from the remote preamplifier make sure that you do not put that signal through
another preamplifier. Almost all consoles switch in a pad in front of their preamplifiers and label the input as
‘line’. If the trim pot still controls level, you are going through a preamplifier. It is best to use an insert return
for an analog line level signal. You will be amazed at how much better everything sounds!
If you are using a digital console without any analog input other than a preamplifier , we strongly recommend
converting the output of the remote preamplifier to digital. We designed a high quality A/D into the Model 188
for that purpose.
The Model 188 and its big brother the Model 1788A fulfill all the requirements for a remote controlled pream -
plifier- great audio, easy to control, no glitches, pops or zipper noise, and multiple outputs.
Introduction
Page 4 Aphex Model 188