PL380 Input Sensitivity

Moderators: Cameron Shoffner, Christian Cook, Kirk Fyvie, Martin Barbour, Gary Evans_QSC, QSC-Dale Sandberg

Thu Jun 23, 2016 8:44 am

  • Can someone please explain the 3 position switch on the back in "simple" terms..

    The manual says:
    •The 26dB (Orange) and 32dB (Green) settings provide the same voltage gain for all models. When using these settings, all
    models will sound equally loud, but the more powerful amp will have more headroom.
    •The 1.2V setting provides the same input sensitivity for all models. Larger amps will sound proportionally louder, with the
    same amount of headroom.
    •The resulting input sensitivities and gains for each model are shown in the Specs.

    In general terms, does this mean that my pl380 will be louder on the 1.2V setting than the 26db setting?

    Thank you
    Possibly an old pro
    Posts: 38
    Joined: Fri Sep 26, 2008 7:02 pm

Thu Jun 23, 2016 9:07 am

Thu Jun 23, 2016 10:07 am

  • The gain/input sensitivity switch will not change how much you can get out of the amp. The amp can reach the point of clipping on any of those settings.

    You still need a good gain structure in your system. For example, if you crank up the amp gain you can make it really loud with only a small input signal, but you might find that noise, buzz, and hiss are very noticeable. So you have to set the gain of the amps and all the other gear so that you get a reasonable signal level throughout.

    There are many online resources for system gain structure; it's not a subject that confines itself well to a single forum thread.

    Here are a couple: ... e-part-one ... mbing.html
    Bob Lee
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    Bob Lee
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Thu Jun 23, 2016 10:44 am

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