sorry my failure;
it's possible in WaveLab, but i wouldn't recommend it;
quoted from the WL help file:
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Live Input
Live Input means that the Master Section is used for real-time processing of signals coming in to the sound card's input(s). This signal can be anything your sound card accepts, for example a feed from a mixer, a tape recorder or a microphone.
1. To activate Live Input mode, select "Live Input" from the Specialized Windows submenu on the View menu, or click on the microphone in the Window controller bar.
2. Double click or right-click in the window that appears, to set up the
attributes for the Live Input.
3. Click the Play button to activate the Input.
By combining Live Input mode with the Record Playback Output mode in the Record dialog (see Preparations), you can record with effects.
I.e. you record the output of the Master Section, including all real-time processing.
4. To resume regular playback of opened waves, click Stop, or click on any Wave window.
It is not possible to start playback of a wave while the Live Input window is active. You must activate a Wave window before clicking the Play button.