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First I want to thank everyone in the forum for so much great information. My wife has a 2002 Z3 2.5 and loves it. So far, with info from here I have fixed the rocking seat, saggy glove box and replaced the rear window with the emiata kit. Now for the question. I'm sure this has been covered many times but I just want to confirm. Can I change the standard subwoofer enclosure (with the 5 inch driver) with the HK enclosure? Thanks.
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There are two styles of HK enclosures. One with two 5”ish drivers and one with a single 6”. I thought all subs after 2000 year were the single but I don’t know for sure. If the current one is a dual voice coil driver then yes you probably could swap if the plugs match. Sub performance upgrade can be difficult using the stock amp if it’s the single amp system
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The current speaker is a dual voice coil. I read all the posts about upgrading and my head is about to explode. If I could fit the single driver HK sub in there, that would be an upgrade from what I have. I can't imagine the cavity that it goes into is different on different model Z3s.
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Yup same same
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I think I see what you mean about there being 2 styles. The ones I was looking at had a rear facing driver with a snorkel and the ones everyone seems to want are the ones with a forward facing driver. There does not seem to be many of them around.
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That’s why I went with a 8” top firing.
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.125 sub box.3.jpg or you can build one!!!
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Or you may be able to fix your current speaker. The foam surrounds deteriorate and are pretty cheap/easy to repair.
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I contemplated fixing the the current one, but I noticed there is a small tear in the cone itself. I ended up ordering the enclosure from Etsy (the forward firing one) and the Kicker 6 3/4", 2 ohm, dvc subwoofer. I guess when I hook it up I will wire the driver in series and abandon one of the existing speaker wire pairs. If anyone has done this please let me know if that is correct. Thanks.
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Ok BUCK57, I just zoomed in on that and it is pretty impressive! Do you have any more pictures from construction? I thought about building one then I found the Etsy (https://www.etsy.com/listing/5126374...er?ref=hp_rv-2) one for $115 delivered and decided to take the lazy man's way out. It's in my wife's car and she barely noticed the woofer was blown. I offered to replace the head unit and all the other speakers and she said she was happy with them. So, the easy solution won the prize. I got the subwoofer but am still waiting for the enclosure to get here. I'll post back when I get it installed and let you know how it goes.
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Do not wire the speaker coils in series. It will sound like crap. I’d wire both coil circuits to original spec.Originally Posted by mc33
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mc33, building this box was worth the effort. It fits the space, the sub works and the sound system sounds good. The box is 1/8 hard board that is glues and screwed. As you can see I braced all joints. My fear is the glue joints will fail with the vibration. So far so good about a month or longer in the M. Kicker states .17 SQ foot minimum interior volume for a sealed box. Based on my crud math, I'm .15/.16 sq/ft. The biggest issue was getting the top of the speaker box to conform with the bottom of the top cover. 4 clicks and it's in!!! Trust me, chop cut glue, chop cut ....................................... it took some time. Now I know what fits, the shape, size and the 4th box will be even better!!!! Will I build another, maybe when the next blizzard hits LA. Build your own, it takes time and I did it with simple tools and trial/error.
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It's ok to do that even though the new sub is dual 2 ohm and not dual 4 ohm? It's the Kicket 43CWRT672.
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Thanks for the pictures. It looks like you used every square inch of space available. It looks great. Part of the reason I was afraid to build one was that I would be on version 6 before I had one I liked. I have the problem of being a perfectionist without the skills to back it up. It looks like you only have one pair of wire inputs. How did you wire the speaker?
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I have the same Kicker Sub. If your existing sub was a Dual Voice Coil then you should have two sets of wires. Connect one set to one coil and the other set to the other coil same as the exiting...Wiring in this manor will convert your 2 Ohm to 4 Ohm just as the factory spec.
Member
It will sound louder but will also put more strain on the amp. Your only other option is source the correct impedance speaker....unless you ditch the stock amp altogether.
Member
I have Pioneer head unit, Hertz 5 channel amp, kicker sub, and hertz in the door (tweeter), kick panel (5 or 5.5 inch) and behind seats (4 inch). The Sub is wired per kicker recommendation with + to one coil, jump - to + on 2nd coil and - on second coil back to car. Loud, yep!! Sound good, yep! Drop the top and crank it up. Still sounds little cause it's a small car with small speakers and poor speaker location. Good thing the Super Sprints are semi quite!!!
If you really want to build your own, I did, it's not hard. I'll take some measurement and post if you'd like. I've thought of doing one more as I learned what worked and what doesn't. I think I can squeeze another 1.3 Sq inches of interior volume!!!! LOL!!!
Now for the next project on the M .......... it's always something
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So I finished the project and here is what I learned. The voice coils in my stock subwoofer driver measured 2.24 and 2.25 ohms. My new Kicker driver measured 2.24 and 2.24 ohms. I'm calling that the same and hooked up the Kicker using both voice coils (not in series). The enclosure I got from Etsy required some modification to fit the newer version of the Kicker driver. The seller said it would so no surprise there. I installed an additional speaker connector on the other side of the box so I could neatly hook up both voice coils. I added some polyfill to the enclosure as recommended in some other posts. I had fairly low expectations going into this because of the size of the sub and the enclosure. After everything was hooked up I was pleasantly surprised. It is not chest pounding bass, but it is definitely way more noticeable than the stock sub ever was. In the small interior is fills the low frequency gap pretty well. If I was going to do it again and had time, I would attempt one like BUCK57 made. It looks like he squeezed every square inch out of that space. To sum up, I spent $115 delivered on the enclosure, $75 delivered on the driver and maybe another $10 on misc stuff. So for $200 and about an hour of my time (plus about 3 days researching, maybe more but sometimes I get lost in this stuff) I ended up with something I am happy with.
Member
Isn’t it nice to actually have some bass and none of the “pop”. If you get any rattling just line the inside of the sub area with dynamat.
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Good to hear that it worked out for you. I recently replaced sub and speakers and kept the factory amps. The sound is decent with the top down and will probably replace the amps when they bite the dust.
Member
Yeah, I'm not messing with the stock amps unless they die. I'm thinking of getting one of those LeatherZ center console arm rests. My elbow has a permanent groove from resting on the edge of the cup holder!
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