I’m getting familiar with the new (fantastic!!) Cella Loudness Meters.
I’m seeing ~6dB difference in sample playback level between standalone VCV (left in image, -7.0 dBTP) compared to the same sample played back in DAW (right in image, -1.0 dBTP). Similar results with several different sample players in standalone. Is there a reason for the difference? This is probably something forehead-smackingly simple that I’m overlooking (eg, some setting in VCV).
I think it comes from difference in levels of signal from external sound and internal sampler. Have you checked if any attenuation is applied to sample in external source?
As far as I can tell, the issue is not your Loudness Meter module. The difference is happening ‘pre-Loudness Meter’.
There’s no attenuation being introduced (by me), but there seems to be attenuation being applied (by VCV). I’m just dropping samples into both, and getting fairly consistent results regardless of samples, sample player, etc.
(Maybe someone else with Pro can confirm the difference between standalone and DAW?)
would be interested to see what “stems” output… (VCV Library - FLAG Stems) it should default to 0dB change, but I’d imagine many samplers default to quieter than the file… the thought being a sample is traditionally as loud as possible to optimize signal to noise in lower bit depths… and playback is often a part of a bigger arrangement…
Perhaps the confusion is the common initial misconception about levels in Rack. There’s a description of it here in the manual, although it’s rather terse and perhaps not so beginner friendly.
So there’s basically two levels to consider: “The master output level” and “The module output level”.
The master output level is the level sent to the audio module/interface in Rack or from your DAW master out. It will typically be the “main outputs” from your mixer. In VCV Rack this is the voltage range -10V to +10V, or in other words, 20V peak-to-peak.
The module output level is the level that a single audio producer is expected to produce, for instance an oscillator or a sample player, which is lesser than the master output level. In VCV Rack this is the voltage range -5V to +5V, or in other words, 10V peak-to-peak.
If you take a look at the following picture you can clearly see the difference.
At the top row we mix two oscillators, which produces 20V peak-to-peak, which equals 0db at the master output - the master output level. Note that the audio module showing -3db is a bit cheating, because as soon as you nudge the signal slightly over 0db it will hit the 0db mark.
At the bottom row we see the output of a single oscillator, which produces 10V peak-to-peak - the module output level, and it is exactly -6db.
So in your example the confusion probably comes as a result of measuring these two different things. You are measuring the output of an audio producing module (the sampler) in Rack (module output level) giving a reasonable -7db output, and comparing it with the master output from your DAW (master output level), which seems to be set at a reasonable -1db.
Hope that helps to clear it up a bit.
Thank you Lars for the excellent tutorial.
Cheers!!
