a few PA questions! so confusing!

Discussion in 'Miscellaneous [BG]' started by Yossarian, Nov 22, 2004.

  1. Yossarian


    Jun 24, 2004
    So my band is looking into getting a new powered mixer. Right now we have an ancient peavey one, 210 watts at 4 ohms. It's too weak. We're looking at the Yamaha EMX68s, but I have a few questions!

    1.) It says channels 1-4 have balanced XLR connectors while channels 5 and 6 have 2 unbalanced inputs. What does this mean? can I still just plug a mic into to 5 and 6 and use them?

    2.) What is phantom power? Searching on here led me to some confusion... is it just for condenser mics? If I have regular mics, should I just leave it off and ignore it?

    3.) How loud will this be? we'll have two 8 ohm peavey 15s, so that's 275 watts per side. That's compared to our current 105 watts per side. Our drummer is unholy loud, so we all end up quite loud... is this going to be too weak?

    thanks for the help!
  2. 1) Channels 5 and 6 are for line-level 1/4" plugs, not mics, I believe. So if you need more than 4 mics you'll be SOL.

    2) You're pretty much correct about phantom power. Some mics and some DI boxes, use an external power supply which is usually 48 volts. So many boards supply this "phantom power". If you don't need it, just turn it off. If one mic or DI box needs it, turn it on, it won't hurt any of the other mics. NOTE: Some mixers provide "phantom power" but at a reduced voltage. This may or may not be an issue, just something to look for when you compare mixers.

    3) Is the Yamaha rated at 275 watts into 8 ohms (or 4 ohms)? 275 watts per speaker is OK, but if the 275 watt rating is into 4 ohm (and not 8) you won't get the full 275 watt power output into an 8 ohm load.

    I think this will be OK, just use the powered mixer for vocals and an acoustic guitar. Don't plan on adding bass into the mix, it'll eat up all your power. A little lead guitar is OK in the mix with this setup.
  3. Yossarian


    Jun 24, 2004
    Thanks for responding! I didn't think anyone was going to reply.

    I'm still a little bit confused about the first thing though. If not mics... what are channels 5 and 6 for? Sorry... this PA stuff is new to me, I don't really know what line-level means. They have two 1/4" plugs and an XLR plug, the XLR makes me think mic.

    The Yamaha, per channel, is 275 watts at 8 ohms and 400 watts at 4 ohms, so the speakers are fine. And we really just need it for vocals, backup vocals, and maybe a little bass drum. The guitarist and I wont be running through it.
  4. Passinwind

    Passinwind I Know Nothing Supporting Member

    Those channels are either for regular low impedance mikes, or stereo line inputs, like say a keyboard instrument. So, yeah, you can just plug in a couple more mikes into the XLR inputs on those channel strips. I went on the zZounds site and had a look at the specs. The reason they mentioned unbalanced inputs is because 1-4 have balanced line ins, which are mono.

    What are your plans for monitors though?
  5. The unbalanced inputs can be used to plug a bass directly into you can plud a DI out of you amp into it. If you need them for Mics go to your local music store and get 2 mic pres It will basically look like a XLR to 1/4" adapter but it will change it to the correct levels.
  6. Yossarian


    Jun 24, 2004
    Passinwind, basically we're thinking we'd start off with the two 15s as mains, one on each channel, and once we get a bit more cash we'd put them both on one channel (then it would only be 200 watts per cab, but that shouldnt make THAT much difference) and get one or two monitors for the other channel. That is, if we really even need monitors.

    That leads me to one more question i forgot about. If we really need more mains, what if we had two 15s on one channel, and then a 15 and a floor monitor on the other channel. The 15s would all face the audience, while we'd have the monitor. any reason why this is a bad idea?

    and by channel i mean sides of the amp, in case that's not making sense.
  7. Just wanted to add something about Phantom Power. Do NOT EVER EVER EVER plug in or take a mic out when the Phantom Power is on.
  8. WayneP


    Oct 11, 2004
    Katy, Texas
    You say the Peavey is “too weak.” If it’s meeting your needs other wise, I suggest just getting a more powerful outboard stereo amp for it. I assume the mixer has connection points for outputs and amp inputs, right? I’m sure you can find a decent amp for the price of this new mixer, especially of you get a used one.

    This would not only give you more power for your mains, but you could use the mixer’s internal amps for monitors in the future, should you ever need them.

    Wayne A. Pflughaupt
  9. Yossarian


    Jun 24, 2004
    oh, the weakness is just the biggest immediate problem with that mixer. it has a world of others problems, hehe. For example, one of the speaker outs in the back doesn't function, and it's missing a plethora of knobs (in a broken off unusable kind of way). We definitely want a whole new setup.