Welcome, Guest. Please Login or Register
Decware Audio Forums
04/29/24 at 09:36:44 




Pages: 1
Send Topic Print
Help with isobaric loading/understanding (Read 3805 times)
DungeonsOfKass
Ex Member



Help with isobaric loading/understanding
07/23/06 at 05:14:17
 
Hey, I want to build a WO for soundquality, but my amplifier puts out 1000watts rms at 4 ohms, i have four fivehundred watt speakers & want to iso load them, and reverse-phase one side.  I want to do it because with reverse phasing one side and with that, wiring the speakers out of phase per side, could the amp maintain a four ohm level?        



                               p.s. sorry about the confusing question, i hope that you will understand the picture

                                                Thankyou, Kass
Back to top
 
 
  IP Logged
Adrian D.
Ex Member



Re: Help with isobaric loading/understanding
Reply #1 - 07/23/06 at 05:40:33
 
you didn't mention what's the impedance of you speakers.
we need that in order to answer your question
Back to top
 
 
  IP Logged
DungeonsOfKass
Ex Member



Re: Help with isobaric loading/understanding
Reply #2 - 07/23/06 at 13:29:58
 
each speaker is rated at 8 ohms




                                         Thankyou,  Kass
Back to top
 
 
  IP Logged
jj420
Ex Member



Re: Help with isobaric loading/understanding
Reply #3 - 07/23/06 at 18:52:13
 
ok with 8Ohms per driver, you would wire each side in paralell to yield a 4 Ohm nominal load.  Thats assuming you will be using one channel per side, for mono operation its a little more complex, but the simplest way is to series each driver in a pair, for an impedace of 16Ohms/pr, then paralell the two pairs to halve the impedance back to 8Ohms.  This way your amp will also live longer, as a higher impedance results in an easier load, letting your amp run cooler.

because isobaric loading puts the drivers out of mechanical phase, you need to take care to wire them out of electrical phase as well, otherwise the assemblies will collide.

the easiest way to do this is to buy the speaker wire where one lead is silver, and the other copper.  put the coppers on positives and the silvers on negative posts of each driver, then tie the wires from each pair together, with silvers of one driver tied to the coppers from the other driver. thats for paralell operation, I get confused when i try and do series and phase at the same time, so maybe someone else better field that one, or you can use a 9V battery and experiment on your own, its only about 5 watts so you wont blow anuything.  Just hook the speakers up to it by themselves with no amp and see which way the cones move, if the cone moves out, then your terminals match those of the battery, if the cone moves in, then the terminals are opposite those on the battery.  After you get used to that, then you can start wiring the drivers together in pairs, unloaded so that when one moves up, the other move down.  In this manner you can avoid costly collisions.  If you are running mono, then the final step is to wire both pairs together and make certain that they move in phase with one another, once you have that determinied, mark the magnets on one side of each pair, so that you dont get them turned around when you mount them.

You want both pairs to be in phase with each other though, otherwise the enclosure will not work properly.

pics?
Back to top
 
 
  IP Logged
Pages: 1
Send Topic Print