kg1961 wrote:I would say your fine with that you plan on using
remember these amp are not new and even we have caps going ect.
I would not use the other amp as you might need extra battery bigger alt. = spending alot more $$$$$money$$$$$
you will be very happy with the 2 ms2125 on the 15" ib subs
remember that is a car not a suv you will have tons of bass
I would psend more time and money working on the front speaker mounting them and getting a good mid bass out of them
its great to have low end but you should have a killer high end
I like it loud but not like the kids in high school all you hear is bass and the speaker are all fucked up
good luck

I'm not sure if you are in favor of one or two 2125s for sub duty, as you've made arguments for both. I'll assume it's intentional and you're being neutral, giving input on both options.
Keep in mind, for mid-bass I will have a 2125 @ 2 ohms stereo running 4 Image Dynamics 6.5" handling from about 80Hz to 1000Hz and a MS275 running a pair of Image Dynamics CD1PRO HLCDs (Horn-Loaded Compression Driver) handling from 1000Hz on up. The horns have a sensitivity of around 105db 1w/1m, so I will have a TON of output available there, and the mid-bass stage should be pretty beefy with four 6.5" getting over 125W each. (these 6.5" play
low very well making them excellent mid-bass performers) I am definitely not neglecting my mids and highs. I'll probably only be using 1/3 of the MS275's output at most, as anything more than that would likely make me deaf in short order.
So, given what I have for the rest of the system, the sub stage is unlikely to be too overpowering under any circumstance given the gear I am using. I know a single 2125 has enough output to hit xMax on the IB15s, but it'll have to be working really hard to do it. If I give each sub it's own 2125, they are under much less stress, allowing them to handle the musical peaks much more easily. Also, the fact that I won't be maxxing out one of my 2125s if I use one for each sub gives me more peace of mind too.
I was already expecting to at least replace the battery. ($200) I'll probably need to do the alt at some point too, as my stock alt is 130A. Still, that's pretty good output for stock. If I have to, I already have a chromed HO alt picked out, available up to 250A. Spendy though, something like $350-450, depending. Ultimately, what I intend to do with the charging system is take a wait and see approach. I'll upgrade it as much as needs to be done once I have it all running and see exactly what I need in practice, rather than in theory.
Thanks for the input, prompting me to think on some other aspects of this,
Brad