dB dBu dBFS dBV to volts conversion - calculator volt volts to dBu and dBV dB mW - convert dB volt relatioship relation absolute level convertor converter decibel to dbfs converter calculation online attenuation loss gain ratio reference audio engine You can measure exactly what your console is putting out with a Vac voltmeter and sine wave tone, across the balanced + and - pins. Professional VU meters are normally 0 VU = +4 dBu = 1.228V, but there's no reason to expect it to be cal'd this way in your system--especially with consumer analog gear that does not have a high max level, it might be cal'd to 0 dBu to give more headroom in the system. It also obviously depends on where the -10 dBV selector is in the signal path. It might not be before the VU meter, and instead is right on the output. Therefore, to get 0 VU you still need to hit +4 dBu, but that's not what you measure out of the desk.