Meterbridge version 0.9.2 - http://plugin.org.uk/meterbridge/

Usage meterbridge: [-r ref-level] [-c columns] [-n jack-name] [-t type] <port>+

where ref-level is the reference signal level for 0dB on the meter
  and type is the meter type, one of:
     'vu'  - classic moving needle VU meter
     'ppm' - PPM meter
     'dpm' - Digital peak meter
     'jf'  - 'Jellyfish' phase meter
     'sco' - Oscilloscope meter
