[TboneS54]

Car - 2011 cic e90 "hifi"
harness - technic
hifi tweets, bavsound 4" mids, L7 8" woofers (4ohm), 10" enclosed sub (4ohm dvc, 2 ohm in parallel)

I've been having a hard time finding an amp that will play nicely with the balanced differential output of the factory headunit, have great crossovers, AND not be silly expensive.

Think I've settled on an ARC xdi850 (that I found at half price), but other contenders were JBL 5ch, JL, Rockford prime 5ch. Point being, none of them give the ability to "band pass" aka place both a HPF and LPF on a pair of channels other than the sub channel with subsonic and LPF.


And I don't want to add a DSP to the mix.

Sooooo

I'm thinking of an HPF of 150hz on the 4"s, and then an LPF of 120-150hz on the 8" woofers, but then I'm going to have to let them play all the way down (40hz?) I'll have an enclosed 10" 500w DVC (in parallel - 2ohm for amp) that I'll LPF at like 70-80hz.

Question - how bad is the breakup of the 8" when not HPF'd at 50hz or so?

If I play the 4" down to 150hz, and the sub up to 70-80hz let's say, will that "hole" be filled in well enough with the underseat 8" if I have to lower the gain on them due to distortion due to not filtering out the freq below 50hz?

I figure that would be better than an HPF of 70hz on the 8" underseats, but then letting them roll off up top around 250-500 or whatever they'll do?

I really miss my 2 way (e46) with 6.7" midbass and 1.1" tweeters. Not loving this 3 way. Trying to make it work without too much gear and $.

Thanks!

Edit:

Couple more things - I'm no EE, I can't make my own crossover unless there's a simple enough guide

I did find FMODs (Harrison Labs) cables that will give me a HPF of 70hz I can use on the 8" midbase, but my concern there is multiple reviews saying that the FMODs claims x-over points aren't accurate (given the resistance) and that they attenuate the line down several db. Well my front and sub are 2oh, my woofers are 4ohm, so already quieter. I know I can raise the gain just on the rear (midbass) channels, but I don't know, it doesn't seem great to me - maybe someone can reassure me?

[kaigoss69]

Only thing I can think of is an Audio Control Matrix or even an LC amp with built in processing/crossovers. I had one in my last car and I loved it. Besides that, FMODs....

[TboneS54]

Have you personally used FMODs? I see a lot of negative feedback (no pun intended).

I actually just found some simple passive crossovers on amazon/ebay - 120hz LPF 12db/oct @ 4ohm which will suffice (I have 4 ohm L7 woofers), and I can then use the HPF of the amp to create the bandpass I think.

I've seen a lot of threads about people amp'ing their hifi system, but I haven't seen much mention of how they employ both an HPF and an LPF, tho I'm sure many have a DSP.

Here's the passive LPF @ 120hz:
https://www.amazon.com/gp/product/B0...ustomerReviews