You want a high signal level as early as possible, and you don’t need to be thinking about the pad until you’ve at least turned the preamp down as far as it will go.
The preamp will go down to +5 without the pad, 9dB below where you have it now. To start with, do that, and turn your receiver outputs up by 9dB. You’ll get a 9dB improvement in signal-to-noise ratio.
Your receivers are outputting a noise floor at a constant relatively low level, and an audio signal that is whatever level you decide. Your preamp is amplifying *both* of these, bringing the audio signal up to where you want it, and dragging the noise floor up too by the same amount. If you output a higher level audio signal from the receiver you won’t need to amplify it as much later, which will improve your signal to noise ratio.
You don’t necessarily “want” to use any gain from the preamp, they’re just there because you need them for when you have a low level source, such as most microphones.
Chris
