Impedance For Stereo And Mono Simultaneously?

Aloha 12 Volters, I have a newb question of all newb questions. If this were drawn out as a simple parallel or series drawing I'd get the math but like they have it drawn in not grasping what the output will actually be. Any help will be appreciated. And since this is so abstract to me if you can explain the math why the outcome is as it is. Ok this is an Kicker 125.2 amp. Little cheapy Walmart $90 hunk of metal. At 4ohm it will run 2 channels at 30 watts RMS (supposedly, this is their wording people) at 2 ohm it will run two channels at 60 watts each and bridged they claim at 2 ohm the output for one channel is 125 watts. But then they show this drawing and That's where the math gets lost on me. Can anyone give me an idea of what the output will be for each channel. 1,2 & "3" please? And you can use whatever resistance you want but if you can try both 2 & 4 ohm levels for me. Or at least tell me what the formula is or why the drawing is making a simple setup complicated in my mind (if That's what's going on) Alpine CDE172BT - Infinity PR6500CS 6.5's - Zapco ST2X SQ - SSA Evil-6.5's Mid-bass - Zapco ST2X SQ - Sundown SD3 12" D4 - VFL Comp 2K... 1995 Lexus GS300 - The Frankenstein build & it changes weekly.

Impedance is relative to frequency. The image shows how to wire two speakers in stereo and one speaker in mono at the same time. The minimum safe impedance for the stereo speakers, regardless of what the crossover frequency is or even if a crossover is used, is 2 ohms per channel. The minimum safe impedance for the mono speaker, regardless of what the crossover frequency is or even if a crossover is used, is 4 ohms. If the speakers shown in the image all have the lowest safest impedance, the amplifier will see a nominal impedance of 2 ohms per channel at, above, and below the crossover frequency if the crossover frequency is the same for the high pass and low pass filters. If the low pass frequency is higher than the high pass frequency, the impedance will be lower than 2 ohms per channel at the frequencies where the filters overlap. the12volt • Support the12volt.com

The only safe way to do this is with a Dual 4 ohm sub wired in series to make it an 8 ohm load across the amp. This in conjunction with the pair of 4 ohm speakers will {no matter how the crossovers are} yield a 4 ohm bridged load.

Yes, a dual 4 ohm voice coil sub would work, but a single 4 ohm voice coil sub would be safe in that application with the proper crossover(s). The amp is rated at 4 ohms mono or 2 ohms stereo. Again, impedance is relative to frequency. the12volt • Support the12volt.com

Ok so let me shed some light as to why I'm even looking at this setup. I happen to have bought a "free-air" sub to replace my factory sub. It is a Titan 10" speaker. It's not so much a subwoofer as it is a full range speaker I think. When I look at it I think guitar amplifier. But short of being able to find a real decent free-air sub like I had in high school that I was able to create a baffle between my seat back and the air space in the trunk of my 81 buick Regal and sealed it up nice and tight. Those were good subs. They did a great job of rattling everything in sight. This speaker is going in the rear deck of my 95 Lexus and as tight as they tried to make the rear deck I doubt seriously that it's as tight as I made that Buick back in the day so I'm not trying to find or recreate that type of setting at this point I'm just trying to fill a hole in the back deck and create a little more mid bass. In doing so I found this speaker cheap and this Kicker amp and two pairs of 5.25 Fosgate full range speakers for the doors. Well I was thinking about wiring this amp up in this configuration and getting the rear 5.25s and the sub too since they all could use a little more power and that would help when I do put a couple hundred watts to a real ported sub in the trunk for my low end. And at that point I'm going to need to put some decent components up front with a little more power to them creating my true sound up front and my fill and center channel from the rear using the "sub" in the rear deck. Now this rear deck sub is 4ohm and I'm not positive about my Fosgate 5.25 but assuming they're 2 ohm is there any idea what I'm going to be dealing with power-wise? Secondly if this going to push this amp past it's boundaries. I mean I'd never think to do it if it weren't for the manufacturers suggestion, but I also know that even they sometimes try to make us believe their products will do more than they can realistically.Alpine CDE172BT - Infinity PR6500CS 6.5's - Zapco ST2X SQ - SSA Evil-6.5's Mid-bass - Zapco ST2X SQ - Sundown SD3 12" D4 - VFL Comp 2K... 1995 Lexus GS300 - The Frankenstein build & it changes weekly.

Ok so too bump this baby up a notch or twelve I'm about to try this on my chest little kicker amp. With my cheap little pioneer 4's and my super cheap (honestly it's probably considered a full range ten inch because it appears to be of the type you'd find in a p.a. or guitar amp. But I do have a 4 ohm passive 800 hz crossover. Ask if these speakers are 4 ohm speakers. So I've got my fingers crossed. The car originally came with a premium sound system circa 1995 and replacing the speakers alone was not enough. I have zero mids and zero bass. I also have a Sony 4 channel that I'm going to use on my front speakers and a real sealed enclosure 12" JBL relatively inexpensive sub. The enclosure is about .18 cubic feet too large currently so depending on exactly how doodiety this might turn out I may be making a box from scratch to spec and/or buying a new sub. In which case I may donate this new JBL to the 12 volt just for one of y'all to have fun blowing it up. Or if you need a $75 sub you can enjoy it. I'll leave that up to the lucky recipient!Alpine CDE172BT - Infinity PR6500CS 6.5's - Zapco ST2X SQ - SSA Evil-6.5's Mid-bass - Zapco ST2X SQ - Sundown SD3 12" D4 - VFL Comp 2K... 1995 Lexus GS300 - The Frankenstein build & it changes weekly.