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Parallel outputs

Discussion in 'Amps and Cabs [BG]' started by bubbles, Mar 11, 2003.

  1. I've got this head i'm trying out from a friend, it's a Yorkville BLOC250B, it's 250 watts, and on the back it's got Parallel outputs, each one is 8 ohms of resistance, but, i was wondering, would each output give 250 watts of power, or would each one give 125 watts? Or am i just insane and have no idea what i'm talking about? The cab i used it with also has Parallel inputs each with 8 ohms of resistance, i'm just wonder what is the purpose of this parallel stuff? is it just two outputs on the head and two inputs on the cab? or what?
  2. ChenNuts44


    Nov 18, 2001
    Davenport, IA
    if two 8-ohm cabs are used, the total impedance will be 4 ohms, which i'm assuming the amp is rated at (250 watts at 4 ohms). without getting technical, each cab will get equal distribution of the total power, or 125 watts each.
  3. redneck2wild


    Nov 27, 2002
    Memphis, TN
    I have an old Yorkville Bloc250B myself that I used at one time as a backup head. I have not used it for live gigs in about 10 years.

    It will handle a 4 ohm load meaning:
    a single 4 ohm cabinet or
    two 8 ohm cabinets
    A fuse will blow if you try anything under a 4 ohm load (such as a 8 ohm cab with a 4 ohm cab).
    It will also blow a fuse if running a 4 ohm load for a long period of time while clipping (2 or more hours). This may be due to heat.

    My Bloc250B ran very hot as there is no fan in it.
    You may try playing the head at a good volume for about an hour and see if it gets hot.
    The main reason I only used it as a backup was that during long gigs, the sound would start changing (possibly due to heat) and would sometimes blow fuses. The amp would sometimes have a grounding hum when the line out was connected to a PA.
    It may have been just the amp that I had but I have ran into a couple of people that had the same problem with the amp.
  4. Petebass


    Dec 22, 2002
    QLD Australia
    Whoa! Never plug 2 inputs into a cab.

    The reason you've got two inputs on your cab is so you can run a link to another cab. So in effect, you can use either as an input, but once you plug something in, the other one must only be used as an output to another speaker.
  5. Thanks guys, i feel like less of an idiot now

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