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

[Ralf Mardorf]

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.
Solo is behind everything.

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
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