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RCF HD-12A over JBL Mpro 4118s

dlbnhdlbnh Posts: 3
edited January 2016 in PA General Discussion
I'm new to your forum but the reading is great. Just got the new DRPA2. It is a bit more involved than my VSX-26 and is going into a new config for my bar band. We play a rock trio with a singer/harp player. Indoor mostly but a few outside gigs. I have 4 each of the HD-12A an 418s subs. We usually use 2 each in a club and all outdoors. QSC 3402 amp for the subs.

So the wizard wants me to set things a bit different from what I'm used to, like xover at 125hz, etc.
I will play my lazy card right up front and ask if I can get a more detailed perspective on proper settings.
Anyone have the prescription?

Thanks in advance,
dlbnh :)


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    DraDra Posts: 3,777
    Considering that the RCF's are not in the wizard's list, that 125 is just a generic number. I like to cross my 12's at 100hz. That keeps the low male vocals and low snare tones out of the subs.

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    dlbnhdlbnh Posts: 3
    I just bought a QSC touchmix so I have opportunity to compact our system a bit. This seems to be working out well. One question I have is time alignment and what seems reasonable? I don't get much time in a gig set up to fuss with this, can you recommend a time alignment? We normally stick a pole in the sub for the tops so the are on top of each other. RCF HD12a on top of JBL MPR 418s. I have experimented with .5 to 3 feet of delay to the tops but can't get enogh time to hear the effect. I also may experiment with driving the subs from an aux send sometime.
  • Options
    DraDra Posts: 3,777
    From the manual (pg 18-19). You can get more context from the entire section (#2) more this is the crux.

    Play the selected sine tone through the system (once
    again, the sine tone frequency should match the set crossover frequency of the drivers being tested) and invert the polarity on
    one of the two drivers being tested – as previously mentioned, this test works best if the sound pressure levels of both drivers
    are matched. Adjust the driver’s levels until the most phase cancellation is achieved. Try adjusting the driver alignment delay for
    each driver to see if any further phase cancellation can be achieved – set it for the most phase cancellation. Note that most
    applications won’t require any driver alignment delay. For more information on setting driver alignment delays, see ‘Delay’ on
    page 39.
    Once you’ve dialed in the driver alignment delay, perform this same “polarity� test while auditioning different combinations of
    filter types in the PA2’s crossover to find the combination of settings which provide the most phase cancellation. When done,
    make sure to switch the polarity back to the proper setting so the drivers will again be in phase.

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