Export TTS from ElevenLabs as WAV, 48 kHz, 24-bit, mono, named consistently. In Audacity set Project Rate 48000 Hz and Import files. Create a noise-profile (0.5–1s room noise), Effect → Noise Reduction → Get Noise Profile, then apply (Noise reduction ~12 dB, Sensitivity 6, Smoothing 3). Then Normalize to −1 dB and light Compressor (3:1, threshold −18 dB). Save these steps as a Macro and use “Apply Macro to Files” to batch-export WAV 48k/24-bit or MP3 192–256 kbps.

See ElevenLabs' export settings page for format options.