[LAD] [LAU] mudita24 1.02 -- improved envy24control mixer/router for ice1712-based sound-cards

Ralf Mardorf ralf.mardorf at alice-dsl.net
Thu Aug 12 21:46:17 UTC 2010


On Thu, 2010-08-12 at 23:32 +0200, Ralf Mardorf wrote:
> On Thu, 2010-08-12 at 23:25 +0200, Ralf Mardorf wrote:
> > On Thu, 2010-08-12 at 23:13 +0200, Ralf Mardorf wrote:
> > > On Thu, 2010-08-12 at 12:42 -0700, Niels Mayer wrote:
> > > > On Wed, Aug 11, 2010 at 1:35 PM,  <fons at kokkinizita.net> wrote:
> > > > > Not really, EQ normally being pre-fader. Post-fader meters in a mixer
> > > > > strip are useful only of the signal being metered is actually one
> > > > > that is physically available on some connector, e.g. as a direct out.
> > > > > It would not indicate any overload that occurs pre-fader.
> > > > 
> > > > The only time I've seen EQ pre-frader is low-cut on a microphone
> > > > preamp. I was using standard "mixing board" definitions of PFL and AFL
> > > > per,  http://www.mackie.com/support/faq/index.html
> > > > ......
> > > > What are PFL and AFL?
> > > > PFL and AFL are acronyms that describe a mixer's SOLO function. PFL
> > > > stands for "Pre-Fader Listen" and allows the user to "solo" or
> > > > audition the audio in mono at a point in the signal path before the
> > > > channel fader. Perfect for a live sound situation where you need to
> > > > dial in an instrument before bringing it into the mix. AFL stands for
> > > > "After-Fader Listen" and allows the user to solo the channel at a
> > > > point in the signal path after the channel fader. This is more
> > > > commonly used for recording applications (the signal is also typically
> > > > after the EQ and pan controls). The Main Output signal is not affected
> > > > by PFL or AFL solo functions, though the Phones and Control Room
> > > > outputs are. On all Mackie mixers, the solo function serves as the
> > > > preferred way to set input levels.
> > > > ......
> > > 
> > > PFL is to level the input, so it's before everything, but the trim.
> > 
> > It's for trim (gain), but for my mixer it's post-EQ and pre-fader. I was
> > mistaken.
> > 
> > > Solo is behind everything.
> 
> Hahaha, for Solo it's the same as for PFL, watching the block diagram,
> but while listening it's be behind everything.

Sorry for another PS, but I guess meters vs listening bus, didn't test
it, but this would be plausible.

> 
> But what I wrote about low-cut, EQs and aux seems to be true, also when
> watching the block diagram.
> 
> Anyway, I need daylight and a magnifier to read block diagrams.
> 
> > > 
> > > I didn't follow the thread, but I guess envy24ccontrol shouldn't become
> > > a complete mixer, but a hw control.
> > > 
> > > > 
> > > > Using a real mixer analogy, here the PFL levels are the current "peak"
> > > > levels from the ice1712 architecture diagram I've posted; its values
> > > > displayed in the meters present in "Monitor Inputs" and "Monitor PCMs"
> > > > panels of mudita24. The AFL levels are available (as I mentioned
> > > > earlier) only by "soloing" (aka muting all others) the channel for
> > > > which the AFL's are being determined, and looking at the resulting
> > > > levels on the digital mixer output.
> > > > 
> > > > In this case, Tim E. Real's:
> > > > "post-fader meter value = pre-fader meter dB value + slider dB value"
> > > > is a trivial computation that could easily be displayed, and would be
> > > > helpful to debug situations like "why can't i hear myself in the
> > > > monitors" (because mute was on). Having a narrow second meter
> > > > displaying the AFL levels (stereo), dynamically shadowing the PFL
> > > > displayed, would be a helpful visualization of mixer function. Even
> > > > more-so with an automatic fall-off of the side peak-level.
> > > > 
> > > > In contrast, it would be less helpful, and potentially more confusing
> > > > to have a modal interface that would require clicking a button to see
> > > > the PFL's, if only AFL's displayed, or vice versa. Especially for
> > > > people that might not be able to tell their AFLs from their PFLs and
> > > > just want to see some dancing meters as sings of activity.
> > > > 
> > > > > If the signal just goes to a mixing bus (as in the case we are discussing)
> > > > > then it's individual level is irrelevant - the level on the mixing bus (all
> > > > > signals summed) may be. But in this case you can't overload the mixing
> > > > > bus, so even that would be useless.
> > > > 
> > > > I think that we are both in agreement that the AFL level meters are
> > > > not strictly necessary.
> > > > 
> > > > However, they may not be sufficient to provide a good visualization:
> > > > having the AFL levels in the meters could help with understanding
> > > > what's actually going on, hidden in the hardware. Similar to how
> > > > useful it is here
> > > > http://osx.iusethis.com/screenshot/osx/traktordjstudio3.png  ...   My
> > > > suggestion would be similar, except that it would either show the
> > > > computed AFL value, or it could be switched to display the overall
> > > > stereo mix output. With its function made superfluous by that option,
> > > > the standalone digital mix meter could go away. Such side-by-side
> > > > metering functionality makes it easier to visualize the level of
> > > > contribution a given input has to the overall mix level.
> > > > 
> > > > > In this case, just individual buttons for L and R instead of the panner
> > > > > would be just fine, and you wouldn't need the mute buttons anynore.
> > > > 
> > > > The mute buttons are useful since there's no "solo" and one might want
> > > > to set levels independently of whether a channel is monitored. The
> > > > individual levels are useful because one might just want to use this
> > > > thing as a mixer anyways, maybe because you don't have another one,
> > > > and because, now that it's adequately metered, it actually performs
> > > > the function of "midi-controlled outboard synth submix" quite nicely,
> > > > and with better fidelity than an external mixer.
> > > > 
> > > > -- Niels
> > > > http://nielsmayer.com
> > > > _______________________________________________
> > > > Linux-audio-dev mailing list
> > > > Linux-audio-dev at lists.linuxaudio.org
> > > > http://lists.linuxaudio.org/listinfo/linux-audio-dev
> > > 
> > 
> 





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