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Spurious results with auto EQ....a little help

vicvic Posts: 10
edited November 2006 in PA General Discussion
Hey erm Gadget...cos you'll probably answer
I tried this outdoor EQ thing on Saturday
Set the gain structure as per the manual/tutorial
Really helped with the punch on the bass
Didn't get an answer about the stereo/mono question so went with the GEQ set to stereo and turned down one of the stacks
Speakers set thus
TXD215 (2 x 15) horizontal on stage
TXD252 ( 2 x 15 + horn) on top, centered over the outer sub speakers - L shaped if you will.
X-over set - sub hi pass - 18dB BW @ 40Hz - x-over at 125Hz 24dB LW
top cab x-over @ 125Hz 24dB LW - straight out at the top
Set the RTA mic on a stand with it pointing on axis between the horn and top driver
Don't quite inderstand what level the pink noise should be set at. I'm worried that a continous tone at high levels could fry a driver
Help here would be appreciated
Any way - I think I got up to -4dB and left it there
The graphic shape had a cut around 80Hz ? and a massive peak +manydB at 16kHz. Now these tops are already pretty fizzy at the top end and quite harsh. I think because either the high level of buffering in full-range mode ensures that the horn always gets it's max power - or - that at 360w programme, it's simply too much power for the highs anyway. JBL only use 150w programme on their horns in similary configured speakers. There were one or two other unexpected lumps and bumps - like some boost around the muddy mids - 500Hz. In the end I just set the GEQ by ear - and it sounded ok - tho a little brittle at top end
Anyone see why I am getting this sort of read out. Oh - I used low res flat response. Would I be better off using the sine tones thru the range using the RTA as a flat response mic and use the pfl function on the desk to check for bumps and dumps at various frequencies. Also, what would be a safe level to run these tones at.
Thanks again


  • GadgetGadget Posts: 4,915
    Sorry man been really busy..
    The HF thing is probably that the horn isn't capable of reporducing that high frequency very well...I'd just set the HF by ear..

    As for the other channel EQ thing on the DRPA I have never used the dual mono setup , but it should be just a combination of the eq button, the fgwd abd back arrows, and the encoder. The 80 hz thing is probably a high 80 hz content in the woofers.. do you sense an overabundance of 80 hz?

  • vicvic Posts: 10
    I didnt detect a lot of 80Hz
    But as an aside
    At another indoor venue - rectangular, playing across the short side
    With the tops and subs end on end - i had a massive amount of 100Hz
    Could have been a standing wave, or possibly the fact that i had 4 x 15\" drivers all coupled together - had to dial a lot out
    i do plan to run a tone sweep at some point using the rta in a desk channel and watching the pfl levels - just to make sure is good enough
  • GadgetGadget Posts: 4,915
    Perhaps this will help explain it.
    Its a room mode calculator. Also see this article:
    http://www.peavey.com/support/technotes ... lation.cfm
    It tells the oposite tale where the Kick magically dissapears.
    remember, RTA a room is not possible without understanding what the sound does in a room. If a cancellation occures you need to do the oposite of what the auto eq does, and that is something only your ears can tell you... Also creative placement, and getting the energy focussed off the reflective surfaces and on the crowd where it blelongs is the BEST method of dealing with these things.
  • vicvic Posts: 10
    already have the calculator and have read the other article
    i guess the bottom line is, as always
    if it sounds good, it probably is
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