2 ohm/4 ohm help?

[SF Doc]

  OK so here it is, I've got 2 Hertz HCX 165s in my 2001 FLHTC fairing (front Channel), and have two infinity 62.11i"s that I want to put in my lowers( for rear channel), problem is my Amp (Kenwood M1804) is 4 ohm which is good with my 165"s but the 62.11i's are 2 Ohm nominal impedance can I wire the infinities in series to get 4 ohms and leave the 165's as is?

Thanks,
    SF Doc

[UltraNutZ]

only 1 pair of Kappa 62.11i?

[SF Doc]

yep just one pair for the lowers

[UltraNutZ]

man you're kinda hosed there.  I would chose a good 4 ohm speaker to use.. maybe something like the CS674 from Kicker.

[SF Doc]

Well that sucks, I guess I have a couple of new 62.11"s that will be going on sale soon! thanks UN!

[SF Doc]

Guess another pair of hcx are not out of the question, so sad!

[UltraNutZ]

actually Doc, according to Infinity; even though they're rated at 2 ohms, they have what's referred to as "true 4 ohm architecture" whatever the hell that is (no beneficial explanation anywhere other than "hear-say").  And now that I think about it.  I was playing with a set the other day and noticed something odd.

a true 2 ohm speaker will typically yield about 1.4 to 1.6 ohm cold when reading with a DMM.  These kappas read in the neighborhood of 2.4 to 2.7 which tells me that it's actually a higher ohm speaker more in the range of 3.0 to 3.5 ohm.

I would put them on there without hesitation and I'll tell you why.  Even though an amp is rated as 4 ohm, it has an inherent capability to drop below 4 ohm by nature without causing any problems.  Go for it!   

[UltraNutZ]

ah just dawned on me.  What they're figuring on is a certain resistance load from speaker wires themselves which I guess if I put about 10' of typical 16ga speaker wire on one and measure it, I bet it's just about NutZ on in being 4 ohms.

[SF Doc]

  Sounds good UN, I will give it a try. Thanks for sharing your expertise and time, you are greatly appreciated.......

[SF Doc]

So one more, do I wire them in series or just as I did with my HCX 165's?

[UltraNutZ]

Are you using speaker level inputs to the amp or the RCA inputs?

[SF Doc]

speaker level inputs

[UltraNutZ]

then I would do 1 of 2 things.

1. Use the rear outputs of the head unit to the rear inputs of the amp and use the rear outputs of the amp to drive the 62.11i speakers
2. use something like a PAC SNI-15 speaker wire to RCA converter then "y" off the RCAs coming out of it into both front and rear RCA inputs on the amp then again run the 62.11i speakers off the rear channels of the amp.

[UltraNutZ]

as suspected.

2.7 ohm at the speaker
10' of 16ga speaker wire is right at .5 ohm
3.2 - 3.4 ohm is what I'm reading at 10'

[SF Doc]

Sorry UN, had to actually work for a while, I like the first option, I have everything at the house to do it.
Glad I don't have to scrap the Kappa's, thanks for the expertise!!