Want to add 2 subs to DSP system

[Nik]

Hello,

I currently have 00 X5 with DSP and Premium sound. overall I'm kind of not upset, BUT I would like more power. At MAX volume BAPing sounds kick in at times of a Bass, once that you hear from ripped speakers, however they are fine... Now I know that AMP is problem most likely here but I don't want to mess with that, Instead I would like to add 2 more subs, so the sound will get better on low volume also
I was thinking of retroing & placing subs under the front seats just like E60 has it. and of course need an amp. Due to the fact that I am not that familiar with the sound system(did some reading on wiki), I ask your help guys. I would want to know if theese will fit each other. Wanted to post in Electronics section but that saying BSW on it, Didn't want to throw links on it. so here it is, a mono amp and sub:

Kenwood KAC-8105D Class D Amplifiers at Onlinecarstereo.com
Amazon.com: Polk Audio db840DVC 8-Inch Dual Voice Coil Subwoofer (Single, Black): Electronics

What do you guys think?

[albarran9]

It depends on how much you want to get out of that amp. With those sub's being dual 4 Ohm coils you can only wire them for a 1 ohm or a 4 ohm load. If you want to get the most out of the subs, an amp that can hold a 1 ohm load will output more wattage than one that can do 4 ohms. As for fitting them in the seats, you'll have to put them in a enclosures for them to sound properly. It depends on the enclosure as well, but there's not much space for 8 inch subs under there. Maybe some 6 inch subs would work in a custom MDF enclosure. CDT audio makes a good 6 inch woofer. You maybe better off ding a single woofer in the rear of the trunk like the one BSW sells that has a higher wattage rating of about 500 or so watts, but depends on you're taste.

[Nik]

Actually I'm not putting it in the seats, I want them under the seats, In the Carpet... As for the size, I think E60s used 8" subs. I will go and see if I can get the OEM E60 subs at junkys. They are Dual Voice I hope right? if not, Ill get theese Subs I guess. Not too much 6"s anyway...
Thanks very much, I searched and found this:
Hifonics HFi1000D Class D Amplifiers at Onlinecarstereo.com - Only this had 1ohm rating.

[albarran9]

woofersect.com may have a better selection. Hifonics is a decent brand for amps. You could also look at shalow mount or infinite baffle subs. A pair of dual coil 2 ohm or single 2 ohm would work nicely with most amps. If you can find one that has level line inputs which will let you tap into the rear left and right channel to power the amp or get a good Line Out Converter (LOC). I used T taps in my E46 to wire an LOC in the trunk from the OEM amp harness. That way I don't have to splice or cut any wires. I've been thinking of upgrading my front speakers with a good set of components up front and placing 6 inch subs in the rear door midrange locations : )
Check these out, they may fit better under the seats
6" Subwoofers

[Nik]

Good news that amp is Good. It looks like it costs 500$ and I have a good deal on it. So i'll order that. I have heard somewhere where it stated that Dual Voice Coil is better? Will I be setting those subs up with 1ohm per sub with this amp? out of which I will get most power @ that ohm am I right? It says that sub has 1000W @ 1ohm that comes to 2 500Ws? Anyway I don't need anything to that strong sub, from 50-70 will do it for me. I'm sorry, I don't know what level inputs or LOC mean, but I saw an arcticle on How to's and that one gets power from OEM amp harness like you mentioned, so thats what I will do I guess. Thanks for the website )

[albarran9]

Yes, a 1 Ohm load will give you more power to the subs. 1000W probably isn't the real rating for those speakers. That must be the peak output for the sub meaning that it will go up to 1000W for a brief moment and not break but not meant to play constantly with 1000w going to it all all times. You want to look for the RMS ratings. RMS is the wattage rating for what a sub can play consistently at all times without any problems. The RMS is usually half of what the Peak power is. So in this case 1000W is the max so the RMS should be around 500 watts RMS for the subs. You will need to feed the amps with a signal from the car because the stock systems don't have RCA's. LOC's just tap into the oem wiring harnesses and give you a Left and Right channel RCA out for the amp's. If you look at this wiring wizard it will help you out when it comes to wiring the subs. Rockford Fosgate® - Woofer WiringWizard

[mrbmwx5]

Originally Posted by Nik

Actually I'm not putting it in the seats, I want them under the seats, In the Carpet... As for the size, I think E60s used 8" subs. I will go and see if I can get the OEM E60 subs at junkys. They are Dual Voice I hope right? if not, Ill get theese Subs I guess. Not too much 6"s anyway...
Thanks very much, I searched and found this:
Hifonics HFi1000D Class D Amplifiers at Onlinecarstereo.com - Only this had 1ohm rating.

No room under the X seats...Why not built a box and put it in the storage compartment in the trunk like we all have done.

[Nik]

I alrady have a Factory sub there. I listened to E60 sound and I liked that kicking in the but I will try, but if not will figure something out. Once speakers and Amp arrives I will use that link and figure it out with the help of electric. Thanks alot guys. I will keep yall posted.

[mrbmwx5]

Nik .. Why not ship your car back here ...I have everthing set up /mod it out and have it ship back to you in Germ....

[Nik]

Thanks Tom. I'd love to, But the shipping will cost me tons of $ so I rather work on it here. It's more trouble, but I'll do it.

How about this? Send me a X with broken tranny, bad driveline, bad cluster, bad DSC block, bad engine and I'll fix everything for 2000-3000$ and send it back

EDIT: Is it bad thing that it doesn't state it has gold plated connectors?