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STEP 9 - ADVANCED AUDIO PROCESSING CONSIDERATIONS
A unique feature of the
RIGblaster pro
is that you may process, equalize, compress or expand
transmitted audio. This is done simply by routing your microphone audio into your computer and back
out to your radio while processing the audio (real time) with appropriate sound card software.
To enable this feature and the ability to make digital recordings of your station operation, you must plug
the jumper on the P6 Jumper Block to send your microphone audio to the computer. See the section
labeled “MIC MODE JUMPER – P6” later in this manual for jumpering diagrams. You must also
connect a cable from the
RIGblaster pro
MIC OUT (R7) to your Computer Sound Card MIC IN to
enable this feature.
Your computer must have an available Mic In and you must have a full duplex sound card that will pass
the sound card microphone input through software and then back out to the
RIGblaster pro
.
To enable microphone audio processing you must turn on the “process” switch (F10). The function of
process mode is to redirect audio from your radio microphone through the computer and back to the
radio.
To utilize Process Mode of the
RIGblaster pro
to process the audio from your radio microphone you
must run appropriate real time equalization software on your computer and set your sound card
recording control panel to feed microphone audio through the software and your sound card playback
control panel to send the audio back in to the radio through the
RIGblaster pro
. Note that this is a
different sound card setup than is used by digital mode sound card programs. You should also note that
if the sound card is set incorrectly you might have feedback and/or echo conditions. You will not hear
your voice coming from the computer speakers as they are muted on transmit in the process mode to
prevent acoustic feedback.
You will have to set the gain of the sound card input and output for minimum distortion and minimum
noise by experimentally determining the optimum settings for your equipment. Do the basic setup with
the equalizer software set to “flat”. Once your have satisfied yourself that your microphone is being
passed through the computer with little or no change you may then experiment with equalization of your
microphone audio.
You will find that only the equalization control in the voice spectrum of 100 to 3500 Hz will have a
noticeable effect on your voice. Trying to boost equalization outside of this spectrum may overdrive
your sound card or radio audio stages with microphone handling and room noises. It is generally
desirable to totally cut or filter out the frequencies outside the voice spectrum range. You should
consider that equalization can be done in any way to make your audio sound either better or worse. You
should try to achieve the most intelligible audio for DXing and general communication. For wideband
FM or AM operation you may want the most natural audio for a high fidelity sound.
If you run compression or noise reduction software all of the same issues of doing equalization are
present.
