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Using head with a power amp?

Discussion in 'Amps and Cabs [BG]' started by seansbrew, May 15, 2005.


  1. seansbrew

    seansbrew Supporting Member

    Oct 23, 2000
    Mesa AZ.
    I have a question, can you run the xlr out on a regular power amp ( say an sm-500) into a slave power amp ( like a crown, qsc) so that you can use both power sections? Does anyone here do this? or do you strictly use a seperate pre-amp with a power amp?
     
  2. i'd imagine that you could, but then again, I don't know much about heads
     
  3. Yes you can. I used to run an Ampeg B2R into my QSC USA900 power amp. Both power sources are available while doing this but it is one HEAVY rig!

    When you think about it it isn't any different than running a line to FOH.
     
  4. dcr

    dcr Supporting Member

    Did this very thing yesterday.

    Ran the XLR out of my SWR Bass 350 into a Crest into an Epifani 410 NYC. Needless to say, it WAS PLENTLY LOUD. And clean!

    Worked great.

    dcr
     
  5. seansbrew

    seansbrew Supporting Member

    Oct 23, 2000
    Mesa AZ.
    I was just thinking of a back up plan, I was going to purchase some new gear for my Shroeder cabs that are on the way, but something came up and I had to use the money for something else. I figure I could bridge the SM-500 into the 1210 cab, send the xlr to the QSC and bridge it (1600 mono @ 4 ohms)into the 21012 cab, or use one side ( 500 @ 4 ohms). I can use this setup until I buy a pre-power amp setup. Luckily my QSC only weighs about 20 lbs, so does the SM-500. :smug:
     
  6. TheChariot

    TheChariot

    Jul 6, 2004
    Boston, MA
    I'm using a B2R as a preamp right now. I chose to use the 1/4" jack (preamp out) though, because it sounds way better to me... but I'm sure that varies from head to head and ear to ear.

    So yeah... its definately an option for you. Take a stab at it.
     
  7. Tash

    Tash

    Feb 13, 2005
    Bel Air Maryland
    I think almost all heads now have line outs, so you could send the preamp signal to a seperate power section. The question is weather of not this will deactivate the amps own power section and prevent you from using both, some do this, some don't. That would depend on the amp's design and should be described in the manual.
     
  8. seansbrew

    seansbrew Supporting Member

    Oct 23, 2000
    Mesa AZ.
    I couldn't find anything in the Manual that addreses this set up ( or the website faq's), I do know that the pre signal will still go to the power amp as well as the line out, I just don't know how strong the signal coming from the Sm 500 is. I also do not know what the max input signal power should be for a power amp. I want to find out before I go hooking things up.
     
  9. IvanMike

    IvanMike Player Characters fear me... Staff Member Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    okey dokey

    on swr you should use either the line out (if it has one - not all their models do) or the effects send. (the effects send on swr is post eq and pre master volume)

    use a "y" cord or an a/b/y box to let the line out from the swr drive both sides of the poweramp.

    i'm not sure how much juice running the xlr out on the swr gives you. i belive the 500 has a pad on it which you could run flat out (i.e., turn it up all the way) when running into a poweramp. not so when sending a signal to a pa. IIRC, generally about halfway up was the max i could run my swr's xlr out into a standard mic input.
     
  10. seansbrew

    seansbrew Supporting Member

    Oct 23, 2000
    Mesa AZ.
    Thanks for the replies fella's, I will try it out when my cabs get here. On second thought, I will try it whith the old cabs first. :p