Hi everyone, I have decided to join your forums to learn more and provide help to what I already know.
Right now I am installing a 15 inch Orion sub into my 1995 318ti BMW and I do not want to screw it up so I am going to list all of my parts here in this post and hope to get feedback on how exactly to tune the amp for the sub and sub box.

The amp is a Kenwood KAC-9105D and here are the specs:

Power Specifications - Subwoofer Channel
RMS Power @ 4 ohms 500 watts x 1 channel
RMS Power @ 2 ohms 900 watts x 1 channel
RMS Power @ 1 ohm >900 watt x 1 channel
Peak Power Output 1800 watts x 1 channel
Amplifier Specifications
Amplifier Class D
Number of Channels 1 - Mono
Total Peak Power Output 1800 watts
Total RMS Power Output 900 watts
Maximum Input Gauge Size 4 AWG
Minimum Impedance Unbridged 1 ohms
Minimum Impedance Bridged Not Bridgeable ohms
THD at Rated RMS Power 0.8%
Speaker Level Inputs Yes
Preamp Outputs 1 pair
Built-in Crossover Low-pass (LP)
High-Pass Crossover Frequency N/A
Low-Pass Crossover Frequency 50 - 200 Hz
Subsonic Filter N/A
Signal-to-Noise Ratio 75 dB
Channel Separation N/A
Bass Boost 0 - 18 dB
Bass/Gain Remote No
Fan Cooled Yes
Fuse Rating 30A x 2
CEA-2006 Compliant Yes


Here is the box specs:


4.0ft^3 Net Volume
Slot-Port Tuned @ 32Hz for MAXIMUM "SQL"
Double-Faced Front Panel (for added woofer support)
Show Quality Custom Carpet
Gold-Plated Binding Posts
14" Round Cutout (slight mod required for oversized subs)
Dimensions (W x H x D): 33" x 16.5" x 21"


Here is the star of the show, my 15 inch sub, just came in today along with box:


Model Number- HCCA152 (Orion)
Power(RMS/Peak) -2000 Watts/4000 Watts
Fs (Hz)-31
Qts- 0.59
Vas (cu ft)- "2.629
Sensitivity- 30dB
Mounting Hole Diameter (Inches)- 15.6
Mounting Depth (Inches)- 12



I am going to upgrade my "big three" tonight, but I am having some trouble finding a high output alternator for this car. I also realize that this amp is kind of small for this sub, but it's going to have to do for now because I cannot afford a nice huge Orion amp at the moment, going to have to wait a couple of months to buy one.
--I need to know what gauge of speaker wire should I use for the sub to sub box terminals, sub box to amp.
--I also need help in what to set the amp dials to, because the last thing I want to do is damage the sub from improper tuning for the amp and box.


I recently wrecked my 15 inch Fusion (NV SW-15) the other day with the exact same box and amp and I almost cried. I had the Fusion for about 4 years now but never thought I would wreck the massive thing! By asking you kind folks for your help I'm hoping to avoid a similar disaster, so I am not going to install the sub until I have proper instruction from you pros.

Thank you for your help in advance and I will be checking this post several times daily.

--Also, I am going to install 0 gauge wire for battery to amp, amp to ground. I am also wondering If I need a capacitor? If so,how many farads does it have to be?
--Is there one I can use for this amp and then also use it for the new amp I will be getting?
--Also, what size of a fuse should I use from my battery to my amp?

 

i dont think u need an ho alt for what you have at the moment. do you know the specs of your oem unit and have you tested with amp meter to see what you are using with all accessories on?? this is the first place to start after the big 3 of coarse
as for tuning the amp! there is a thread here i believe by Father yuli do a search and ye shall find..
for wire and fuse sizing go here: http://www.bcae1.com/wire.htm
there are tons of info on that site, but scroll down and you will find what you need.
caps are a waste of time and money, if you need a cap get a second batt or upgrade your existing one to a bigger better agm.

good luck and welcome to the forum
there is a ton of info and good advice here. i have learned a lot

Dan

 

Thanks nghtrdr, update I upgraded my big 3 with 1/0 gauge wire, and I still have the same problem that I had before I upgraded, when I have a hard hitting bass song and the bass kicks in, the RPM's go down with each bass hit, also, when I'm driving I feel studders in my throttle and I lose power with every bass hit. Seems like I'm drawing too much power for everything to handle. The alternator is a brand new 80 amp. And the battery is brand new also. Would it help if I put on 2 caps on the amp? I'm at a loss here because shouldn't upgrading the big 3 stop all of this?

 

Not a whole lot of input here...do I need to donate or something?

 

I think first figure out your amperage draw minus stereo then come back to us. On a BMW 80 amp depending on case size you could have it rewound to roughly 120 amp if you have a good rebounder local.

Lymen

 

Update (if anyone cares lol) put sub into car, @1 OHM 900 watts later ima go see what it can do...sounds pretty sick too! I would love a bigger amp tho

 

sounds like ur cars computer controls the alt. this would explain the studders u speak of. i have read this can be an issue. im no expert though.
as for the cap. save ur money and add a second batt in the trunk near the amp. this will work way better and will stabilize ur electrical system. caps dont do but give u a millisec of output. a batt can do this and gives u storage. i just changed to odyssey for my primary and secondary batts. these things are amazing. very low internal resistance too, pricey but worth it.
an alt is good if one is available for your car and is affordable. this is one area where u def get what u pay for.

let us know how it works out for ya..

 

Ya, money is not an option on this build, another battery will have to do I guess, as for now the bass is amazing, just need a bigger amp now!

 

Switching forums these ones are dead....