The Subharmonic Acoustic Scanner  is a piece of equipment that can effectively track down any form of ecto acoustics.
After an encounter with a Banshee, the Ghostbusters failed to capture her. Roland Jackson and Egon Spengler isolated the Banshee's vocal frequency  and programmed the Subharmonic Acoustic Scanner to track it only, after Janine Melnitz lugged it up three flights of stairs. Roland was the only one who knew how to use it so he went into a Syren concert alone to keep looking for Banshee but he was enthralled by Siren.
- Roland Jackson (1997). Extreme Ghostbusters- Sonic Youth (1997) (DVD ts. 04:37-04:38). Sony Pictures Home Entertainment. Roland says: "It's a Subharmonic Acoustic Scanner."
- Roland Jackson (1997). Extreme Ghostbusters- Sonic Youth (1997) (DVD ts. 04:39-04:44). Sony Pictures Home Entertainment. Roland says: "While you two were rehearsing for the Super Bowl, we successfully isolated the Banshee's vocal frequency."