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PA for Subwoofer management

andy2667andy2667 Posts: 3
edited August 2011 in PA General Discussion
Hi I want to buy either a PA+ or PX for bass management for my home audio system. May use it for full speaker management and EQ later but will use it for bass management first. I want to clarify the following before buying one:

1. True stereo bass/ subwoofer output?
- I note that the output for bass/ subwoofer are marked as Left/mono and Right. Are the outputs for bass/subwoofer true stereo or arethey summed to mono providing pseudo stereo only?

2. Phase adjustment available?
- my subwoofer amplifier do not have phase adjustment. Is phase adjustment available for the subwoofer outputs? Individual adjustment possible?

3. XLR to single end (RCA) connection
- my subwoofer amps are Single end with RCA input only. Note that the PA+ provides XLR outputs only. Can I simply use an XLR to RCA connector/cable for this connection or I need a Balanced To non Balanced transformer.

4. What are the major differences between PA+ and PX? Or other recommended mdels are better for bass management?

Sorry for my dum questions and thank you for sharing.

Andy

Comments

  • GadgetGadget Posts: 4,915
    Welcome..
    1. True stereo bass/ subwoofer output?
    - I note that the output for bass/ subwoofer are marked as Left/mono and Right. Are the outputs for bass/subwoofer true stereo or arethey summed to mono providing pseudo stereo only?

    Yes... it can be either summed to mono (left mono out) or true stereo...
    2. Phase adjustment available?
    - my subwoofer amplifier do not have phase adjustment. Is phase adjustment available for the subwoofer outputs? Individual adjustment possible?

    PX has absolutely NO adjustment for phase, delay or even polarity... the DRPA has alignment delay of 10 ms(10 feet~)... but only the 260 has "phase" it also has over 1/2 mile of delay...

    Listen... I challenge you to tell me HOW yopur going to tell when the "phase" is correct, because without sophisticated measurement equipment your ONLY guessing...
    3. XLR to single end (RCA) connection
    - my subwoofer amps are Single end with RCA input only. Note that the PA+ provides XLR outputs only. Can I simply use an XLR to RCA connector/cable for this connection or I need a Balanced To non Balanced transformer.

    To go from XLR balanced to 1/4" or RCA simply ignore the pin one (1 shield) and use pin 3 to tip and pin 2 to the sleeve...

    The PX is a 2 in 4 out unit with 28 band GEQ, 3 PEQ's on hi outs and 2 Peq's on the low outs...no delay all the crossover and filters that the DRPA PA+ have here is a comparison of the PA and 260...:

    viewtopic.php?f=60&t=2114

    Hands down the 260 is THE primo controller... I would not get the PX for your application... but it would work..

    Gadget
  • andy2667andy2667 Posts: 3
    Thanks Gadget for the information and clarification.

    Concerning the Phase adjustment for subwoofer, I am confused! I read a lot from online forum that phase adjustment for subwoofer is important for seamless integration between the sub woofer and the satellite/main speakers.

    I previously owned a bass amp with phase adjustment. I adjusted the phase by listening and try to get the most loud and boomy bass by adjusting the phase nob. I actually heard the differences.

    That is why I am now quite concerned about phase adjustment for sub woofer.

    It seems that I have to upgrade from DRPA+ to DR 260 because of the phase adjustment???! The cost differences is not small.

    Thanks again but I am now even more confused on the phase adjustment after received your comment.

    Andy
  • DraDra Posts: 3,777
    To the novice, phase, polarity, and delay interaction are all the same thing. To a pro audiologist that is into the physics of sound (not me...) phase polarity and dely are all diiferent creatures. The phase control on the bass amp you had may have been a simple delay for alignment. The only problem I see with a bass delay (only) is that for it to work the sub can't be farther from the listening point that the mains. This means that the sub has to be (for example) behind your couch, of at some point closer to you than your mains. If your sub needs to be farther way from you than the mains , for whatever reason, then you have to delay your mains. The DRPA+ will allow for either, but is limited to 10'. So as long as the sub and mains are within 10 feet (perpindicularily (SP)) of each other, the DRPA+ will work fine for you.
    If you need more than that or if you want true 180 deg phase control and switchable polarity and up to thousands of feet of delay, then the 260 would be needed. Check Ebay or Craigs list, also PSW's Maketplace for a used 260.

    DRA
  • DennisDennis Posts: 801
    The delay function is all you need to time align and phase align (basically the same thing) a sub. Just because you have the function doesn't mean you know how to use it....it's not something you set correctly by ear
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