Need help, 2012 Mazda3 with Bose - Want to keep OEM H.U. but add sub/components/amps

[divide_by_zero]

I decided I'm sick of the factory bose system in my 2012 hatch with bose. From the OEM the car comes with an amplifier under the passenger seat, and a 10 speaker system.

The factory speakers are:
2 speakers in the front doors
2 tweeters in the sail plate near the side mirrors
2 speakers in the rear doors
2 speakers in the back where the c-pillars are
1 center channel speaker in the dash
1 "subwoofer" (if you want to call it that) where the spare tire is.

I want to do:

6.5" components in the front doors with the tweeters mounted in the factory spots
6.5" components in the rear doors with the tweeters mounted in the back c-pillars where the factory speakers are.

12" sub in the back, in a ported hand built box.

I am going to eliminate the factory bose "subwoofer". I see no need for the factory center channel speaker in the front so I intend on disconnecting this as well.

I have attached the bose wiring for the 2011 and 2010 I hope this is the exact same wiring as the 2012 model (can anyone confirm?)



Based on my findings, some users have used the bose inputs (the left connector in the photo above) - I want to use this same. Apparently the signal is just an analog ac voltage.


Here is what worries me.

I am not completely sure if the signal is flat coming from the factory headunit to the factory bose amplifier. What I mean is, bose is notorious for equalizing thier sound systems to what they think sounds good. Hopefully this equalization is inside of the amplifier, (which would be completely removed and out of the car) I do know that when fiddling with the factory system the sound knob has an option for "audiopilot" - I left this off, think it sounds better.

Has anyone completely confirmed that the low level inputs going to the amp are flat?

I have searched for about 30 hours solid and not found exactly what I am looking for. I found someone who used a JL cleansweep, but I don't like the idea of not being able to use the OEM volume knob. I do not have a problem with buying a sound-processor but I want the functionality of the OEM radio to be completely intact.

[divide_by_zero]

No ideas yet?

[Redakuma]

to answer your question the signal from the deck to the amp should be a clean signal.

as long as you plan to run wires to all speaker locations back to your amp and tap in the stock head unit with either rca converters or an amp with speaker imputs you should be fine.

if i were you i would reconsider the separates in the rear, its over kill and not beneficial just put up some coax's in the rear. (assuming your not going for a Sq car) .

i had an 07 altima with bose that just lacked low end, I added an amp and sub and was happy with that set up. Gl

[divide_by_zero]

Originally Posted by Redakuma

to answer your question the signal from the deck to the amp should be a clean signal.

as long as you plan to run wires to all speaker locations back to your amp and tap in the stock head unit with either rca converters or an amp with speaker imputs you should be fine.

if i were you i would reconsider the separates in the rear, its over kill and not beneficial just put up some coax's in the rear. (assuming your not going for a Sq car) .

i had an 07 altima with bose that just lacked low end, I added an amp and sub and was happy with that set up. Gl

I was going to chose seperate for the rear so I would have 2 extra speakers to put into the C-pillars where there are already 2 speakers from the factory. (even know the factory speakers in the c-pillars are 3 inches or so)

My plan was to de-equalize the signal back to flat with some digital signal processor. I am currently leaning towards the the Alpine PXE-H660.

[divide_by_zero]

Anybody can give any feed back for the Alpine PXE-H660 for my application? I've done some searching, I read just about every thread with the H660 in it on this forum. Using my original OEM HU factory volume control is a must for me. I've also been eyeballing the H800 as well but the price is much higher and I think the H660 has what I need because once I get it tuned I probably will never change it.

[mcqueena]

Originally Posted by divide_by_zero

Anybody can give any feed back for the Alpine PXE-H660 for my application? I've done some searching, I read just about every thread with the H660 in it on this forum. Using my original OEM HU factory volume control is a must for me. I've also been eyeballing the H800 as well but the price is much higher and I think the H660 has what I need because once I get it tuned I probably will never change it.

I have a 2010 Mazda 3 sedan that came with the standard non-Bose system. I started out with the factory headunit with an Alpine PXE-H650. I replaced the front components (active) in the factory door locations and disconnected the rears (are you sure you want to run rear components?). I also added a 10" sub. It sounded good, but the volume control sucks. I never measured it, but I'm pretty sure the low end is rolled off as you turn up the volume. This is probably to protect the cheap factory speakers. Because the eq of the system changes with the volume, there is no processor that will really work well using the factory volume control. Maybe the Bose system doesn't have this problem.

Recently I changed out the headunit and the results were staggering. I difference in clarity and volume was amazing. Plus now I have full control of my system from the headunit. Everything about the new headunit is superior to the factory. They only thing I gave up was looks, but my ears are happy.

I say all of this to say you may want to consider replacing your headunit. If you'd like to try the PXE-H650, I have one I'd sell you for cheap. Send me a PM if you're interested.

[divide_by_zero]

Originally Posted by mcqueena

I have a 2010 Mazda 3 sedan that came with the standard non-Bose system. I started out with the factory headunit with an Alpine PXE-H650. I replaced the front components (active) in the factory door locations and disconnected the rears (are you sure you want to run rear components?). I also added a 10" sub. It sounded good, but the volume control sucks. I never measured it, but I'm pretty sure the low end is rolled off as you turn up the volume. This is probably to protect the cheap factory speakers. Because the eq of the system changes with the volume, there is no processor that will really work well using the factory volume control. Maybe the Bose system doesn't have this problem.

Recently I changed out the headunit and the results were staggering. I difference in clarity and volume was amazing. Plus now I have full control of my system from the headunit. Everything about the new headunit is superior to the factory. They only thing I gave up was looks, but my ears are happy.

I say all of this to say you may want to consider replacing your headunit. If you'd like to try the PXE-H650, I have one I'd sell you for cheap. Send me a PM if you're interested.

The H660 is supposed to fix the volume problem as far as I understand. I intend on calibrating it at the volume that I listen to it, so that should hopefully fix the roll-off problem. If it came down to it, I would keep the system 100% factory before switching the headunit.

[mcqueena]

Originally Posted by divide_by_zero

The H660 is supposed to fix the volume problem as far as I understand. I intend on calibrating it at the volume that I listen to it, so that should hopefully fix the roll-off problem. If it came down to it, I would keep the system 100% factory before switching the headunit.

Good luck.

[divide_by_zero]

Today I conducted an experiment, to understand how good the signal is from the factory bose stereo. The project was done to intercept the signal between the factory head unit and factory amp. To do this, I made a connector that would mate to the factory harness and provide a stereo signal a path to my computer. From here, I use a Linux to monitor and record 1 minute of white-noise (which is equal power at all freqencies) which had been burned to a CD to play in the factory cd player. I took data at 6 different volume levels (10, 20, 30, 40, 50, 60 - bass/treble set at zero) and compared the shape of the output curves to the shape of the source. I was extremely pleased with the flatness of the signal as I found that it DOES NOT change with volume.

Here are the graphs for the front, rear and source (volume was 40 here)

FRONT:


REAR:


SOURCE:


All 3 together (Front Red, Rear Blue, Source Green)


As you can see there is a small roll-off in the high end range that starts at about 17K, and gets progressively stronger around 21K. This range is very high up in human hearing and you can probably not even tell. The good thing is that this is a consistent roll-off that does not change with volume (I observed this exact phenomena at all volumes tested)

I am really this came out like this, I'm going to proceed with this project now. Getting a good signal was really stressing me out, I guess our bose decks are actually very modification/friendly.

[mcqueena]

Interesting test. Maybe I'll test my non-Bose head unit. I would expect them to be the same but maybe they have different tunings.

[shamie]

Nice graph!

I know you're leaning towards the Alpine gear, but have you considered the JBL MS-8? I just notice Crutchfield (normally high priced) has it on sale for $300 off:
JBL MS-8 Digital sound processor at Crutchfield.com

[divide_by_zero]

Originally Posted by shamie

Nice graph!

I know you're leaning towards the Alpine gear, but have you considered the JBL MS-8? I just notice Crutchfield (normally high priced) has it on sale for $300 off:
JBL MS-8 Digital sound processor at Crutchfield.com

I was really only thinking about getting a digital sound processor because I was afraid of the worst, that the bose headunit would have been rolling off frequencies. Since this is not true, I will take the low factory inputs to the bose amp and run it through "the matrix" by audiocontrol. I'm not interested in timing correction or anything like that, I just want the signal to be flat.

[shamie]

Since its a flat signal why run it through any processing then? Just run it straight to your amps.

[divide_by_zero]

Originally Posted by shamie

Since its a flat signal why run it through any processing then? Just run it straight to your amps.

because I want to boost the pre-amp signal, cleanly. During my experiment I found the signal is pretty weak.

[kelrog]

very interesting findings, I also have a mazda3 2012, but its a speed3 w/tech

I will be adding a sub in the tirewell soon, so I've been looking to do about the same as you.

I have been pleasantly surprised or just getting used to the bose speakers in the car, minus the sub, though it is hand and feet above what I got with my RSX bose system.

subscribed, hope the install goes smoothly for you.

[divide_by_zero]

This weekend I installed some sound deadener. I finished the liftgate and did the majority of the rear of the car. Once I had the trim apart I removed the old 3" factory bose speakers and made adapters out of plexiglass so I can install the polk component tweeters there. I do not know the cutout size for the tweeters so I will not cut that hole until the components come in a few days.

[kelrog]

Take any pics of what u did with the deadener?

I just got my si bm installed today. I had to fade the front to 7 to blend with the sub.

[marshdrummer]

I just purchased a 2012 Skyactive 5-door with the Bose...I'm thinking about adding just a 10" sub in the rear jack compartment....Thanks for posting the graph...it answers a lot of people's questions!

I'm thinking a Polk MM1040 with 100RMS to it...would that be a good fit?

[kelrog]

10 on 100rms sounds kinda low, especially since it will be sealed. There are many shallow mount 12's out there that would fit in the spare tire and replace your bose sub.

I just did some wire taps into a cut off rca cable. You just cut the ends off one side, strip and tap into the bose amp input. I tapped the rear channels, brown/pink and lt blue/lt green (first black connector on the right)

I tried using the sub output directly into the rca of my amp but it put it into protect mode since it was a high level signal. (was hoping the amp could handle it)

The newer 2010's have the sub amp under the passenger seat, sending only the speaker outputs to the sub, where as previously the amp was in the same tire enclosure in the back.

[divide_by_zero]

Originally Posted by marshdrummer

I just purchased a 2012 Skyactive 5-door with the Bose...I'm thinking about adding just a 10" sub in the rear jack compartment....Thanks for posting the graph...it answers a lot of people's questions!

I'm thinking a Polk MM1040 with 100RMS to it...would that be a good fit?

I would suggest the JL stealthbox for something like that.

[GreggG]

Originally Posted by kelrog

10 on 100rms sounds kinda low, especially since it will be sealed. There are many shallow mount 12's out there that would fit in the spare tire and replace your bose sub.

I just did some wire taps into a cut off rca cable. You just cut the ends off one side, strip and tap into the bose amp input. I tapped the rear channels, brown/pink and lt blue/lt green (first black connector on the right)

I tried using the sub output directly into the rca of my amp but it put it into protect mode since it was a high level signal. (was hoping the amp could handle it)

The newer 2010's have the sub amp under the passenger seat, sending only the speaker outputs to the sub, where as previously the amp was in the same tire enclosure in the back.

Hi guys, I'm going to add an amplified sub to my 2012 Volt. It has the Bose system as well. I need more bass and figured adding the amplified sub would be the easiest. The sub has both low level and hi level inputs. Should I use the Bose amp outputs to the Bose sub and put them in my new amp high inputs? I read somewhere else that someone put the Bose HU amp in wires to the low level inputs of their amplified sub and got better base. I have the sound system electrical schematics, so I just need to know the best way to tap into the existing system in order to add the new amplified sub. Any input would be greatly appreciated.

[kelrog]

Originally Posted by GreggG

Hi guys, I'm going to add an amplified sub to my 2012 Volt. It has the Bose system as well. I need more bass and figured adding the amplified sub would be the easiest. The sub has both low level and hi level inputs. Should I use the Bose amp outputs to the Bose sub and put them in my new amp high inputs? I read somewhere else that someone put the Bose HU amp in wires to the low level inputs of their amplified sub and got better base. I have the sound system electrical schematics, so I just need to know the best way to tap into the existing system in order to add the new amplified sub. Any input would be greatly appreciated.

depends on how you want to use your amp. Use the high level inputs on the new sub amp with the bose speaker output or the low level from the stereo before the bose amp to your low level sub. Try the easiest first, high inputs probably and if you aren't happy try the low level approach. Most bose and amp combo will sound slightly different so no right answer if you aren't going to replace it all.

[GreggG]

Thanks for the input Kelrog, I'm just using the powered sub to improve the weak bass of the Bose system. I like bass, and there is not all that much. So hook the HU rear speaker wires (pre-amp) to the low level inputs on my powered sub? Or hook the Bose amp sub speaker outputs to my High level powered amp inputs? If I do the High level inputs, do I tap into both L & R speaker wires and connect them together at the new sub amp? Sorry if these are stupid questions, I just don't want to blow anything up, and I'm not a stereo person.

[kelrog]

Originally Posted by GreggG

Thanks for the input Kelrog, I'm just using the powered sub to improve the weak bass of the Bose system. I like bass, and there is not all that much. So hook the HU rear speaker wires (pre-amp) to the low level inputs on my powered sub? Or hook the Bose amp sub speaker outputs to my High level powered amp inputs? If I do the High level inputs, do I tap into both L & R speaker wires and connect them together at the new sub amp? Sorry if these are stupid questions, I just don't want to blow anything up, and I'm not a stereo person.

Yes if u go from hu before bose amp tap rear L and R. If u tap high level output after bose amp hook them to both high level inputs on new sub amp.