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Confused about mono/stereo and pink noise behavior

Randall dRandall d Posts: 14
edited September 2014 in PA Configuration Wizard
I have a PA with two powered subs and two powered 2-way speakers on top with a PA+. I want to plug all speakers individually into the back of the PA+ due to how I prefer to physically run my cables. In Wizard I selected mono input and stereo subs and stereo tops. Of course I run into the hated right/left balance issue in Wizard, but once I faked that out, I went on to Auto EQ and the pink noise only came out of one side of the system. How do you run a mono system and still use the left and right outputs on the PA+? Can I just set it up for a complete mono system, and still just use the left and right outputs on the PA+? (I don't have the PA here to try).


  • DraDra Posts: 3,777
    I don't own a "+", but perhaps you should take your mixer's output and split it to use both inputs of the PA+.

  • So you are thinking that maybe the PA+ is looking to see if anything is plugged into the right channel input; and since there isn't, it doesn't output the pink noise to the right channel outputs? If I have it set for mono input and stereo output, wouldn't you think that it would output the pink noise to both right and left outputs?
  • DraDra Posts: 3,777
    Sorry, misread your post.
  • I figured it out. I had the Graphic EQ set to Dual Mono instead of Linked Stereo. Makes sense when you think about it, but it is a little counter-intuitive (using Linked Stereo for mono applications, and Dual Mono for stereo applications).
  • DraDra Posts: 3,777
    Go figure.
  • What is the latest greatest method for auto-eq'ing? There is the FAQ's and then there are threads that seem to amend or contradict those methods. The FAQ says to point the mic at a reflective surface on the floor or ceiling about as close as you can get the mic to the surface, and then there is the method of pointing the mic at the speakers about 25 feet away with the mic laying on a peice of carpeting on the ground (seems like that would pick upi too much bass causing the Auto EQ to make it top end heavy). Then there was the technique of using an outdoor EQ to set the PEQ to get it as flat as possible outdoors before taking it to a club and using the Auto EQ, and then there was a thread that said that it was better to just do the Auto EQ without having the PEQ. So I am a little confused as what the current best practice is. Is there a somewhere you can give me a link to that covers the whole procedure using the latest-greatest method?
  • DraDra Posts: 3,777
    Those are all different circumstances.
    1) Outside (away from all reflective boundaries (except the ground) - One side of stage stack (if you center stack you subs, use half of them with your stack). Mic 25' in front, on a stand pointing (leveled) at the low driver of the full range cabinet.
    This is for system flattening and balance.

    2) The point the mic tip at, and very close to, the floor / ceiling / wall... it to reduce the far reflections from affecting the results. (The very close reflection will be very much louder than the far ones, so it will dominate.)

    3) The lay the mic on carpet (or better... a very thick / folded towel on the floor or table) method reduces the effect of the close reflection. Stand not needed.

    2 & 3 are basically the same, but are used for pinking the room you are in to minimize resonances and nulls. Your choice as to which you utilize.

    Hope that helped.

  • So if setting up in a typical (yeah, I know) small - medium size club, which method do you recommend for pinking your system? We are running one sub and one satellite on each side. Satellite center is 6'-7' off the floor, subs on the floor. Running mono. Classic rock: e-drums, bass, two guitars, keys and vocals. No guitar amps, just bass amp and floor wedges.
  • DraDra Posts: 3,777
    I use the towel on the floor / table / chair method, because it is easier.

    At 7', depending on vertical dispersion...
    40 deg - at least 12' from the speaker,
    50 deg - at least 15' from the speaker,
    60 deg - at least 19' from the speaker.

    Whatever the distance, it is best to have the wall facing the speakers (rear of the room) at least 2, 3 (or more) times that distance from the mic. Side walls also, if possible. That make the direct sound much greater than reflections.

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