這個可以做多種音量測量的 meter plugin 還可以做 matching，而且還是免費的！ http://www.tb-software.com/TBProAudio/dpmeter2.html TBProAudio has released dpMeter II, a precise digital audio multi channel meter including RMS, EBU R 128, and TruePeak (intersample) measurement. It is the successor of their popular dpMeter and adds manual loudness, peak, and TruePeak matching. dpMeter II features a very straightforward UI with graphical metering along with numerical readouts for RMS, peak, crest, loudness, and TruePeak, their name for intersample peaks, a kind of prediction of the analog condition at the listener’s end, after the conversion from digital. TBProAudio dpMeter II is available now for free. It requires OS X 10.5 or later and an AU, VST, RTAS, or AAX plugin host.