[NC] Making Bose work, and exceeding expectations (Pics). Plus sound deadening (2024)

Blackone

Join Date: Dec 2005

Location: Florida

Posts: 4,203

NC 2006 GT. ( Disclaimer If you screw up your car is not my fault)
After reading just about every post on the dreaded Bose issue, I decided to put all of the forums experience and knowledge to work, Credit to all of you who have posted, and especially to the Capitan who provided the all important wire diagrams ( Kirk are still on the fence, or did you update your system?) Also great credit goes to MNPRHT and his incredible research and post. And to otherhand, for his scholarly investigation on sound deadening.

So here we go… the beginning.

How to improver your Bose system for about $120? Well just follow the advised from MNPHRT:

http://forum.miata.net/vb/showthread.php?t=244979

I replaced the Bose tweeters for Infinity Kappas http://www.crutchfield.com/app/produ...1%2F2&x=33&y=8
And added the inductor and capacitor

Capacitor: http://www.madisound.com/catalog/pro...a10c6c5af80d82

Inductor:
http://www.madisound.com/catalog/pro...roducts_id=966

Do not be afraid to modify the door panel so that they fit, just make sure window is up and use a ball hammer is soft metal. I also trimmed the plastic door panel (with a dremel) where the speaker attaches. Easy!
I chose the Kappas because they are 2 ohm's, I also added Dynamat to the whole door. Make sure you secure (with Dynamat) the thingy that has the only Phillips screw when you remove the plastic panel inside the door, (near where the door lock un to the b pillar)this piece is lose and emits the nasty rattle when you play a high bass note on your Bose.
Follow the wire colors from his link to install the capacitor on the drivers door is the green wire, passenger yellow with red stripe

The results.
This mode alone is sufficient for great sound. The bass from the Bose turned out to be fantastic, kind of like a small subwoofer, it clears up an does not distort at full volume. Limiting the frequencies to it, and dynamiting the door was all it needed. The Kappas add what was missing nice mid and highs with a nice warm increase on volume. In total the improvement was fantastic and most people will completely happy with this mode alone. I believe this mod will give you better results than is you did a bosectomy with only 2 channels because it will be hard to achieve the bass that you get from the Bose woofer from a speaker that fits in that hole.
This mode is highly recommended
Cost $ 120 plus cost of dynamat
found 36 sqft for $135 here) http://cgi.ebay.com/ws/eBayISAPI.dll...m=110429223212

Like I said for the average person this mod will suffice, but No for me, oh no…because I suffer of compulsive behavior I decided I wanted more so here is what I did:
I Added
Alpine amp MPR F300. this gives 75 wt RMS at 2 Ohms. times 4
http://www.crutchfield.com/app/produ...+300&x=35&y=17
Infinity Kappa 690.8. Nice speaker $139 from here
http://www.hookedontronics.com/show_...97&brandtype=0
Crutchfield list them for $249
http://signature.crutchfield.com/App...ssi=0&skipvs=T

The only problem is that I needed to intercept the 2 rear lines from the head unit and there was not a clear picture of this procedure or color wire descriptions, so I used the Capitan’s diagrams to intercept them right before they connected to the Bose Amp.
http://forum.miata.net/vb/showthread.php?t=160108

Here are the wire colors before the Amp
R – Green with orange stripe 1F (wire diagram )
R + Green with Black Stripe 1H

L – Blue with Yellow Stripe 1J
L + Yellow 1L

Getting to the amp is not hard, just remove the passenger seat so that you can sit low and see it, move a part the insulation and there it is you need to unplug the blue connector this easy just press on the 2 opposing tabs and pull out

Next isolate wires, I used zip ties to do this. Then attach speaker cables, this will go to AMP low level input

Note on signal, as established by others the signal coming from the head unit is a Nice clear stereo signal and is a balance and low level, so you need to get an amp that accepts a balance signal here is a list of Amps .(or you could get a line converter.)
http://forum.e46fanatics.com/showthread.php?t=528285

OK now you have intercepted the lines from the head unit you will be able to plug this to the Low level RCA plugs on your amp but you need this wire.
http://www.crutchfield.com/p_136CLR2...&ssi=0&tp=2610

Next place speakers on rear cubby holes using particle wood 1/4 and I placed the tweeter here .

PIC

the amp fitted under my seat nicely. (But I do have my seat modified) I think it will fit under a standard seat too or it can also be placed standing up behind seat.

Results:
UNBELIBEBLE!!!!!!! THIS THING SOUNDS GREAT, the front has a deep punchy bass, the rears are clear and bright the location of the tweeters gave an incredible imaging.
This combination work better that I had expected. I use my IPod or CD and this ting sounds as good as the Harman Kardon Logic 7 system with 13 speakers In my BMW, and I still got 2 channels unused on my amp that I can bridge for a sub, but even I (Mr. compulsive) can see that there is no need for one, as the front Bose woofer is strong and the speaker behind the seat kicks against my lower back.

So for a few hundred dollars the car is been transformed.

Now a few observations on sound deadening, I read the impressive report done by otherhand http://forum.miata.net/vb/showthread...fat+lady+sings

He only registered a 1 dBA improvement for all his effort, and wile this my be accurate, I can tell you that with the addition of Dynamat at least the tone of the noise has changed to a more endurable frequency.
I will especially recommend doing the transmission tunnel, between the shifter and the fire wall, if you tap it here you can tell this is the culprit of the high speed drone with the top up, it is also bell shape which in theory dissipates sounds perfectly. Also do the rear shelf where the Bose amp is. I stuffed 2 pillows there in the empty crawl space and boy I’m happy with the results.
If you going to do dynamat get ready is hard work and it will cut your hands all over, little paper cuts, ouch!!
I hope now some of you who are sick of substandard sound in your cars will now feel confident of tackling this project, yes you. You know who you are!

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