Those socket look like mil spec circular connectors for microphone connections.
https://uk.rs-online.com/web/c/connectors/circular-connectors/mil-spec-circular-connectors/?applied-...
https://www.ebay.com/itm/New-Unused-14-9-Plug-2-pin-Connector-f-WW2-Old-Vintage-Aircraft-Radar-Radio...
If you want to use this compactor, my suggestion is re-terminate those inputs to rca or xlr socket.
https://uk.rs-online.com/web/c/connectors/circular-connectors/mil-spec-circular-connectors/?applied-...
https://www.ebay.com/itm/New-Unused-14-9-Plug-2-pin-Connector-f-WW2-Old-Vintage-Aircraft-Radar-Radio...
If you want to use this compactor, my suggestion is re-terminate those inputs to rca or xlr socket.