Possible Clues:

• Studio feature that produces reverb
• Place where it all comes back to you?
• Nymph has bedroom that creates sound effects
• Radio studio feature, and what each of this puzzle's four other longest answers literally is
• Space that reflects sound
• Sound modifier The Cavern might have provided?
• Recording space creating reverberation
• Recording studio feature
• Room for reflection
• Place for creating sound effects