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AFS in Live mode

jiffscojiffsco Posts: 5
Hi folks: I have a question regarding the use of the AFS. I have gone thu the steps of setting up the gain structure and completeing the out door Auto EQ / PEQ flattening for the speakers. I set up my PA for 2 gigs this past week and had a problem using the AFS. Perhaps I don't fully understand it's use.

I set the unit with 6 filters in Fixed mode and 6 in Live mode. I raised the mains up until the system fed back and the AFS captured and notched the 6 feedback points perfectly. However, when I swithced the unit to Live mode...the AFS would only activate when a screaming rip of feedback tore off our heads and it did not activate or capture every time. You could hear feedback points beginning to build during the event but the AFS would not capture them. I tried Music low thru High, Speech...everything.

I should add we had a mixture of Live Music and Speech (with a Feedback prone lavallier mic, and I swithced the AFS Live mode to the appropriate setting)

My question is this...Have I misunderstood how the AFS Live mode works? Does it not detect a feedback point in the midst of Music and filter it out leaving the music intact? If you have to wait until a burst of feedback detroys your hearing it seems to me that the unit isn't functioning or set up correctly. Have I misunderstood the AFS Live function? Other than that I'm thrilled with the unit.


  • GadgetGadget Posts: 4,915
    A lav mic is hopeless.. they SUCK... no feedback eliminator of ANY kind will capture all feedback from an omni directional POS lav mic... Wherever possible I like to make headsets and tape those ^%#&#&R(%( things to them.. a coat hanger and a little tape turn a NIGHTMARE into a cool sounding USABLE mic...otherwise, lighter fluid :lol: is the only way to fix them so they won't feed back...Actually, if you can dedicate a 5-6 band PEQ to the LAV or a 31 band Graphic, and hack the frequency response to HELL you MIGHT be able to get them to work ... MARGINALLY...AND you better have a system that is tuned to the nuts...

    The problem is an OMNI mic, behind and below the voice of the user...with a small element...and crappy frequency response to boot...

  • DraDra Posts: 3,777
    I've found that stapling the mic wire to just above the chin works great. That way the sound guy and the presenter both feel the pain.

    Seriously, over the ear and taped to the temple is fair. If they wear a hat, taped to the brim. Glasses, taped to the frame.

    Jack Bauer's in ear mic might work nice, but he might have to kill you.


    PS - I heard that Minnie Pearl's dangling price tag was actually a lavalier. 8)
  • jiffscojiffsco Posts: 5
    (Laughing) I hear ya about the Lav! But my main concern was with how the AFS live mode is supposed to function. The Fixed mode worked as expected. Does the live mode detect and notch feedback before it rips your head off? Does the Lift/ time setting influence the sensitivity of the unit's ability to detect feedback? Was the RTA mic supposed to be plugged in while operating the AFS Live mode?
  • DraDra Posts: 3,777
    The RTA mic has NOTHING to do with AFS. If you used it at all, back up and punt (start over).

    Are you using the GUI? Do you have 12 total filters selected? And 6 fixed? As a test, select 12 total and zero fixed. Are they being caught same as before? If you have the fixed tab selected the \"Lives\" will never kick in because you are telling it to work on the fixed.

  • jiffscojiffsco Posts: 5
    I did not have the RTA mic connected. I am using the GUI. I had 6 fixed and 6 live. After the fixed had caught...I selected the Live mode tab. The problem is not that the Live wouldn't catch at all. The problem was that the Live would only catch everynow and then....letting feedback thru and sometimes not catching at all ,with the feedback just ringing out until I muted the channel. And at a volume that hurt. (this was during soundcheck only... During the performance I rode the faders and used the Notch filter to isolate a few of the frequencies. It helped tame the Lav mic and overall the presentation was successful.)
  • DraDra Posts: 3,777
    It has been my experience that the hotter the signal in the 260, the quicker the feedback is trapped. In other words, high output at the mixer and amps turned down some (but still feeding back). The main problem is that that messes with the overall gain structure. You gain headroom, but lose output. But again, maybe you amps are too hot to begin with.

  • jiffscojiffsco Posts: 5
    That makes sense...I did turn down the amps during soundcheck in order to be able to raise my Mains fader but I could have turned them down further. The mains fader was not as far up as it should have been and the signal into the 260 was not as hot as normal. (it was a Church gig with lots of elderly and I didn't want to blow them out of their seats. I'll take a smaller PA next time.)

    I'll try running the board hotter at my next soundcheck next week and let yu know if there's a difference. Thanks all....
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