SAC Question

[Lance]

Regarding the faders issue...

It seems to me that for live sound, in a virtual console world, there could be a form of automation which senses feedback on a specific channel and would auto reduce the gain for that channel to adjust for the feedback. An indicator light to tell the engineer which channel was compensated would then help the engineer to adjust that channel for whatever caused it to feedback, i.e. EQ or FX.

This would be a fairly simple function because feedback would be readily identifyable on any given channel as a product of that channel, no matter what the frequency of the feedback. It's a much simpler function than a "feedback destroyer" which tries to identify the center frequency and notch it out with a narrow filter. Even if the console were able to identify the center frequency of the feedback, I would want the adjustment to be in the hands of the engineer rather than automation.

However, a simple automatic ride of the gain to stop the feedback imho would be entirely acceptable.

This would eliminate much of the need for instantaneous access to a specific channel gain on the fly.

In fact, with a virtual console, any feedback could automatically cause the screen display to pop up the offending channel...indicate the center freq. of the feedback and the relative gain necessary to compensate...!!! And it could do this way before the feedback reached ear splitting level.

I think that I would prefer this direction to computer/digital based SR, rather than the direction that Digi, Midas, Yamaha, et.al. have taken with their digital SR products...which seems to me just a remake of analog methods. Reminds me of a digital emulation of a mini-moog in a hardware package which looks just like a mini-moog.

Stuck in an old paradigm.


Lance

[Leadfoot]

if there's a way to do it, that's an excellent idea!! i'm already thinking of next festival season and how i could pull this off with sac. three areas i'm concerned with are, access to faders, latency(stabilty of computer system) in a critical live situation, and what to use for a front end. i'm not totally sold on the behringers (ada8000) in that situation. i really hope to be on the forefront of this technology out there with sac. if it works, i can already see the faces especially those that spent 100k on a digital console..
i'm hoping the potential benefits of such a system would far outweigh the possible difficulties.

tony

[Craig Allen]

It's the feedback detection part of that equation that scares me. The Behringer feedback destroyers detection algorithm is just plain bad - it actually notched out the kick drum (when there was no low end feedback happening). Of course, there are better algorithms out there, but I'd be scared that someone might be holding a note and it think that would be feedback. I would rather have an indicator of what the console 'thinks' and then take action myself if needed.

[Leadfoot]

good point about the feedback. an indicator would be good, we could take it from there. i just re-read my post and i didn't mean to make it sound like "i'm" on the forefront.. i know craig and others have already done live sound with saw. i just meant in my little part of the world i'm still worried about a windows computer in front of 30 or 40 thousand watts of power.

tony.

[Lance]

It's the feedback detection part of that equation that scares me. The Behringer feedback destroyers detection algorithm is just plain bad - it actually notched out the kick drum (when there was no low end feedback happening). Of course, there are better algorithms out there, but I'd be scared that someone might be holding a note and it think that would be feedback. I would rather have an indicator of what the console 'thinks' and then take action myself if needed.

I agree with you about the feedback detection part of the equation relating to notching out frequencies. I've had similar problems as well with the Sabine boxes which have a very good algorithm.

However, I'm just talking about detection of a channel that's feeding back and lowering the gain automatically for a short period to stop the feedback. For this kind of detection, anything that looks like a sine wave without related overtones, at a specific frequency for a steady state could trigger the circuit. Or simply pop up the channel on screen for manual adjustment.

Even a long guitar sustain would not look like feedback to this type of a detection circuit because it's a more complex signal. Of course this combined with thresholds, like maybe a steady state at pre-clipping...

Then again, I'm not sure that I would object to the virtual console automatically ducking the channel when the guitar got too loud

Anyways, just some idle thoughts on my part...

Lance

[IraSeigel]

Then again, I'm not sure that I would object to the virtual console automatically ducking the channel when the guitar got too loud

Lance

Now you're talking, Lance. It would surely be worth a couple grand to have the algorithm that would dim the lead singer -20dB when he (or she) was being an a--hole!!

Ira

[Lance]

Now you're talking, Lance. It would surely be worth a couple grand to have the algorithm that would dim the lead singer -20dB when he (or she) was being an a--hole!!

Ira

Well, if it walks and talks like a duck... then I guess that's the way it should be treated.

Lance

[Bob L]

Well, the feedback indicator ideas are all good and many more interesting features will start to come along as this technology starts to eveolve...

But... first things first... let's get the virtual console up and running and stable and accepted as a useful concept... then we'll evolve it way beyond the physical consoles it will replace.

Should prove to be a fun ride.

Bob L

[Michael Naz]

Most touch screens only respond to a single input area. And I would guess that SAW is only written to respond to a single input area (ie mouse) so I would expect that you can't pull multiple faders in that way.

Dominic

The JazzMutant Lemur that was mentioned at the start of the thread responds to multiple input area at the same time, its one of the things that makes it a lot more expensive then a small lcd touch screen right now.

[bcorkery]

Will SAC be for live, FOH only, or will a stationary studio be able to fully appreciate it?