Psst... Ready to join TalkBass and start posting, make new friends, sell your gear, and more?  Register your free account in 30 seconds.

bi-amping question

Discussion in 'Amps and Cabs [BG]' started by jnightmare, May 1, 2005.


  1. jnightmare

    jnightmare

    May 12, 2004
    Carson, CA
    i have a bi-amping question. like for example the ashdown can bi-amp and provide 575+575 watts at 4 ohms. now looking at the back pannel there is a jack labeled left and right speaker. now my question is do you have to still plug in two 8 ohm cabs to make it 4 ohms to get the maximum wattage or since there are 2 jacks you plug in a 4 ohm cab to each and you'll get the maximum wattage?
     
  2. jnightmare

    jnightmare

    May 12, 2004
    Carson, CA
    also if you only plug in one 4 ohm cab its just getting 575 watts only right? (this is probably a no brainer stupid question but i suck with technical stuff) thanks for the help.
     
  3. IvanMike

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

    Nov 10, 2002
    Middletown CT, USA
    well it sounds like this amp has 2 seperate poweramps each capable of producing 575 watts each at 4 ohms.

    its my guess there's a switch to engage a crossover to send highs to one amp and lows to another, or when it's off each amp gets the full range signal (my preference). most people mean the former whan they say biamping, but technically when you use two amps full range you're bi-amping as well.

    anyhow, check out the ohms faq linked to the faq sticky at the top of the forum for adetailed exlination of this but here goes. yes, in order to get the full 575 watts out of each side you need to plug in a 4 ohm load to it, which will be either one 4 ohm cab or two 8 ohm cabs. an 8 ohm cab by itself will probably still get 300 or so watts, which will still be pretty darned loud. other factors like the number and size of the drivers in the cab, the sensitivity of the cab and the overall voicing of the cab will affect how "loud" it sounds regardless of impedance
     
  4. jnightmare

    jnightmare

    May 12, 2004
    Carson, CA
    well i already understand ohms and stuff but the whole thing on having 2 power amps confused me i didnt know if you still had to plug in two 8 ohm cabs or if you could just run a 4ohm plug in two 4ohm cabs since you have 2 power amps.

    this question also came about because i saw a live video performance of a band and from what i gathered the bassist was playing through a svt2 pro which can run 300 tube watts at 4ohms and 2ohms. it also is similar with 2 input jacks in the back for speaker cabs like the ashdown i mentioned. and he had 4 ampeg 8x10's on stage, with 2 on each side. now i noticed the ampeg 8x10 only comes in 4ohms and i didnt see him have another amp or anything but on one side of the stage he was on. so essentially hes running at what 1ohm since 4 4ohm cabs would do that. so i was wondering how that was possible, thats how my question came about. i didnt find any additional equipment on stage besides the one svt2 pro and a rack tuner and an avalon u5 and maybe like a power conditioner too.
     
  5. IvanMike

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

    Nov 10, 2002
    Middletown CT, USA
    well just cause you didnt see it doesnt mean it wasnt there. ;)
     
  6. Tash

    Tash

    Feb 13, 2005
    Bel Air Maryland
    Most likely he was running a seperate power amp for each pair of 810s and just using the SVT2 as a preamp. The poweramps were likely racked with the bands PA gear, which is why you didn't see them.
     
  7. jnightmare

    jnightmare

    May 12, 2004
    Carson, CA
    yeah true you got me. but yeah just seeing it got me thinking cause ive been considering an ashdown amb500 and also the amb900 caught my eye and i was curious about the whole biamping with 2 power sections if that changed things. but i guess it doesnt. thanks for the help.