How can I remove hiss in a recording (due to too-low level preamp)?
This was a live recording that I took from the mixing board on a Tascam, at 24-bit 96kHz recording. It has the direct input from the keyboard and the mics from the bass already mixed down to one stereo track.
Although it worked fine in rehearsal a few hours earlier, the keyboard came though at a very low level for reasons that were never determined (the plugs etc. were checked between numbers!)
So, the sound board operator had no choice but to crank the input up on the keyboard. This produced a noticeable hiss. Furthermore, he did a good job of ducking the level when he wasn’t playing, so the hiss comes and goes and changes volume all over the place.
The sample file is representative: you can hear how the hiss starts out loud and fades out when the other instrument (only) is playing.
I’m using Adobe Creative Suite, so what might I do in Audition to improve this?
(Note: I also have a recording made using a stand-alone Zoom recorder, in case that proves useful. I presume the direct recording is better for the clean-up though, as the recording of the speakers playing the hiss with natural room reverb added would be even more complex.)