# Preston Electronics, LLC Preston Electronics, LLC
Lee's Summit, MO

 HomeContact Us Answers to brain stretchers (If you haven't already figured out the answers, you're cheating!  I'll probably have to fix your amp one of these days!) Five 8-ohm speakers would have a total impedance of 8/5 or 1.6 ohms. Six 8-ohm speakers would have a total impedance of 8/6 or 1.333 ohms. Seven 8-ohm speakers would have a total impedance of 8/7 or 1.14 ohms. Eight 8-ohm speakers would have a total impedance of 8/8 or 1.0 ohms. I'll leave it up to you to figure out what happens with 4 ohm speakers. Equivalents for a combination of a 4, 8, and 16 ohm speaker should use the 16 ohm speaker as the reference. One 8 ohm speaker would be the equivalent of two 16 ohm speakers. Since one 4 ohm speaker is the equivalent of two 8 ohm speakers, it is also equivalent to FOUR 16 ohm speakers. So, 4 ohm and 8 ohm and 16 ohm equivalents are: 4(16s) and 2(16s) and 1(16) = 7(16s) in parallel, or 16/7 ohms = 2.286 ohms (same as we got the first time!) A "Minimum 2 ohms" load could be: Two 4 ohm speakers (4/2) Four 8 ohm speakers (8/4) One 4 ohm and two 8 ohm speakers - 2(8s) and 2(8s) =4(8s) =8/4 =2 ohms and many other combinations The following chart may help to remember.  (The symbol "//" means "in parallel with".)                              2  =            4            //           4  =    8     //   8               8    //   8 = 16//16  16//16       16//16  16//16 