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QSC USA 850 Question

Discussion in 'Amps and Cabs [BG]' started by Pre EB, May 30, 2002.


  1. Pre EB

    Pre EB

    Mar 15, 2002
    Denton, Tx
    Forgive my ignorance, but how can I run both output channels of the amp with one input? I'd like to run a 15 off one side and 210 off the other. I know how to bi-amp but I'd like to see how it sounds full range mono. Do I need a Y cable? Flip the bridge switch?
    Thanks,
    Joe
     
  2. I'm not familar with the features on that QSC but many power amps can be configured to drive both channels using the same input source or to use individual input sources for each channel. Some amps do require that you use a Y adapter.

    When you bridge both channels the amp should only use one input source.
     
  3. Pre EB

    Pre EB

    Mar 15, 2002
    Denton, Tx
    It uses only channel one input when you bridge and can only run one speaker cable out. This amp seems to be pretty bare-bones, but it sounds good and seems to do the trick. I might just run the 210 full range and have the 15 going out of channel two from the low pass output of my pre. I know that'll rock. I am curious to see how I could run two sides from one input.
     
  4. VicDamone

    VicDamone

    Jun 25, 2000
    My 2402 came with a well written multi lingual user manual with directions on setting the DIP switches on the back pannel. You got any a dose?

    No...try the website.
     
  5. is there a "parallel" on the mode bswitch. my phonic max 2500 has stereo, parallel and bridged.
     
  6. Pre EB

    Pre EB

    Mar 15, 2002
    Denton, Tx
    No DIP switches (Whatever they be) and no parallel switch either. Just one that says stereo or bridge. Like I said bare bones.
     
  7. VicDamone

    VicDamone

    Jun 25, 2000
    QSC amplifiers are some of the most flexable. If you don't have the user manual you'll need to log onto www.qscaudio.com click pdf's then manuals and scroll down to the USA series. I didn't see an 850 but there's an 900. Print out the manual and read it front to back.
    You own a durable amp that may last a liftime and you should learn and know how to use it.
    Pay close attention to the parallel inputs and bridged output sections.
     
  8. the manual i have from their site for the 850 shows DIP switches on the back. Run it in parallel mode, one input will then be fed into both outputs, with each having its own volume and limiter controls still.

    Greg

    btw, on their site its the manul for the RMX 850, 1450, and 2450 all in one.
     
  9. Pre EB

    Pre EB

    Mar 15, 2002
    Denton, Tx
    Mine is the USA series. I think the RMX has more features. I guess I'll read the manual!:rolleyes:
     
  10. I have the 850. to run full range from one input, use the panel in the back. It has screws for each channel. Run a wire from channel one's signal to channel two's signal.

    Does your amp have side holes on the binding post? Mine's so weird- the posts unscrew and all, but there are no holes except for in the back.
     
  11. Pre EB

    Pre EB

    Mar 15, 2002
    Denton, Tx
    That's the one!That is weird, isn't it. I wanted to be able to use banana plug for my cables. Oh well, I'll just get a Y cable or bi-amp for these cabs. Or read the manual! Whatever comes first:D So far Ive been very happy with it and my rig sounds great. If only I had the time to be in a serious band. You know how a wife and kids change priorities! I really enjoy the forum, though. Good advice and a wealth of info.
     
  12. Bob Lee (QSC)

    Bob Lee (QSC) In case you missed it, I work for QSC Audio! Gold Supporting Member Commercial User

    Jul 3, 2001
    Costa Mesa, Calif.
    Technical Communications Developer, QSC Audio
    Pre, send me an e-mail at bob_lee@qscaudio.com and I'll send you the manual for the old USA series.

    There is no switch on the USA 850 for connecting the inputs in parallel. Either use a Y-cable on the inputs or attach wire jumpers on the screw terminals of the input barrier strip: + to +, and - to -.
     
  13. To go a little off topic, Bob, do you know why the posts screw in and out, but there aren't any sideholes in them on the USA 850?
     
  14. Bob Lee (QSC)

    Bob Lee (QSC) In case you missed it, I work for QSC Audio! Gold Supporting Member Commercial User

    Jul 3, 2001
    Costa Mesa, Calif.
    Technical Communications Developer, QSC Audio
    Hi Davy,

    All the binding posts QSC ever used have had side holes. The holes face down on your model.

    It's possible that over the years someone cranked the barrels on the binding posts so tightly with nothing in the holes that it torqued the posts. If that happens, the holes in the posts won't line up with the holes in the base of the binding post assembly. The remedy is to open the top of the amp (with it disconnected from AC, of course). Inside, you'll see nuts that secure each binding post. Loosen the nuts just a little bit so you can turn the posts counterclockwise until the side hole lines up with the hole in the base. Stick a banana plug into the side hole of each binding post to hold it in place while you tighten the nut. When you're done, put the top cover back on.
     
  15. Thanks alot! The holes are on the bottom:)

    I expected holes on the side of the posts that were hidden when screwed in!