Audacity Forum

And I haven't actually tried this, but I'm betting the music is too quiet or the hiss level is too high for the noise gate to be effective.

Do you have 'Play Tacks While Recording New Ones', 'Software Playthrough' or 'Hardware Playthrough' selected in Audacity Preferences? Turn them all off or deselect them and restart Audacity. Still hear it when you press Record?

Koz

Amplify the track to 0dB then try these settings with the Noise Gate (latest version available here: http://forum.audacityteam.org/viewtopic ... 824#p84824 )

Gate (Link stereo)
Gate Frequencies above: 8000
Level Reduction: -9
Gate Threshold: -9
Attack/Decay: 1000

This will cause the gate to gently ride up and down with the dynamics. The very high frequencies on the piano are only present for a short while as the hammers hit the strings, when the gate is open. When the gate closes, it attenuates frequencies above 8kHz. It's not perfect, but it retains the sparkle of the piano (and some noise).