Hello everyone.

Vittorio and I have been discussing his ReplayGain branch. Its purpose 
is to prevent differences in track loudness by normalizing the levels of 
all tracks. (This is what ReplayGain is all about.)

Currently the ReplayGain value is read from tags (or calculated if not 
present) and applied transparently, before the Gain and Volume 
sliders/knobs on the skin. This results in the average volume of the 
tracks being around the center of the (pre-fader) channel VU meters (if 
no initial boost is applied.)

This bothers me because, in the analog world at least, you want to 
maximize the dynamic range of the input stage by adjusting the pre-fader 
gain so that the signal is as high as possible but not clipping. (You do 
this by increasing the gain until you see clipping then backing it off 
slowly until the clip light no longer illuminates.) Then you use the 
volume/level fader to adjust the channel's relative volume in the 
overall mix. (So if a channel is quieter than another, its volume slider 
gets raised above that of the louder one.) I do this in sound 
reinforcement scenarios, when I DJ with my analog mixer, and when DJing 
with Mixxx (all have pre-fader channel VU meters.)

Given all that, it makes the most sense to me for the following to occur:
1) Peak-detection finds the loudest transient in the track and 
automatically adjusts the (pre-fader) Gain knob so that that loudest 
transient is just below clipping.
2) ReplayGain value is read/calculated and automatically adjusts the 
deck _volume_ slider to compensate for the volume difference. In order 
for this to work well, the volume sliders would need to default to 
something other than 100% so there is somewhere to go in either 
direction. (Maybe 75%?)

(Note that this has nothing to do with the master output level, which 
should only be controlled by the DJ to adjust the main overall floor 
volume as needed.)

Also, I plan on implementing soft-takeover for MIDI controllers that 
have physical knobs & sliders so the auto-adjusting won't be a problem.

Let me know what you all think. Thanks for your attention.

Sincerely,
Sean M. Pappalardo
"D.J. Pegasus"
Mixxx Developer - Controller Specialist

------------------------------------------------------------------------------
Nokia and AT&T present the 2010 Calling All Innovators-North America contest
Create new apps & games for the Nokia N8 for consumers in  U.S. and Canada
$10 million total in prizes - $4M cash, 500 devices, nearly $6M in marketing
Develop with Nokia Qt SDK, Web Runtime, or Java and Publish to Ovi Store 
http://p.sf.net/sfu/nokia-dev2dev
_______________________________________________
Mixxx-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/mixxx-devel

Reply via email to