Fixing your MAZDASPEED3 BOSE Sound System

[1sty]

A few things.
1. a capacitor limits low frequencies, creates a high pass crossover when in series
2. an inductor limits high frequencies, creates a low pass crossover when in series
3. either of them attenuates at -6dB/octive, this is a first order crossover.
4. Crossover caluclator: http://www.the12volt.com/caraudio/crosscalc.asp
5. Cheaper replacement speakers use just a cap (capacitor) or coil (inductor) as a crossover.
6. Component speakers use a much more complex network, unless you have a really good understanding of acoustical and electrical components, don't even go there.
7. Bass blockers are just a capacitor and they have many to choose from. The problem is that the frequency of the crossover changes based on the speakers impedance. The bass blockers are listed frequencies for 4 ohm speakers. With a 2 ohm speaker that will double. So an 80 hz bass blocker on a 2 ohm speaker will actually be 160 hz.
8. Any car with this many speakers often uses internal digital sound processing (DSP) to limit the frequencies each speaker receives. So there does not need to be anything external. This is called an active crossover. So unless someone has done an RTA on the amplifier outputs, not on the speakers response mind you, then you have no way of knowing what frequencies are actually being sent to that speaker.

 

[kvndoom]

8. Any car with this many speakers often uses internal digital sound processing (DSP) to limit the frequencies each speaker receives. So there does not need to be anything external. This is called an active crossover. So unless someone has done an RTA on the amplifier outputs, not on the speakers response mind you, then you have no way of knowing what frequencies are actually being sent to that speaker.

I haven't looked, but does the blose amp send a different signal to the front woofers and tweeters, or is it one output that is run parallel? There's no way a speaker can "know" what is being sent to it and self-equalize. So unless the driver's side amp is six channels and has a separate speaker output for the woofer and the tweeter, the woofer is getting a full-range signal without a crossover of some sort, even if it is just a lowly single inductor.

And honestly, that statement almost made it sound like you think Bose knows what they're doing. If they've made such an elaborate system that sounds so sub-par, I'd have to disagree. (lol2)

 

[Bluesfish]

I just purchased a new MS3 GT 2 short weeks ago.
While I've never been a fan of Bose products I find, so far, I can live with the sound. Coming from a stock Ford sysem in a 2001 sport-trac it's quite an improvement. My biggest complaint is the huge level difference between the radio and the Aux or CD changer. I have to turn it way up to get a good level for the CD or my Ipod (Ipod at full boost) and if I switch to the radio I get blasted!

Anyone else notice this?

 

[Mid_Life_Crisis]

I haven't looked, but does the blose amp send a different signal to the front woofers and tweeters, or is it one output that is run parallel?

It`s a five channel amp. Two fronts, two rears, and a subwoofer.
The woofers are allowed to roll off naturally (meaning they are chosen because they don`t do a good job of reproducing high frequencies) and the tweeters have the one cap on each, which is probably there more to protect them from low frequencies than to block low frequencies for sound quality purposes. Everything about this system screams that it should benefit from putting a band pass filter on the woofers. A bandpass filter is just what it sounds like: it allows a selected band of frequency to pass through to the speaker. In this case something like 100 to 3500hz (as a 6db/octave - higher if 12db) should probably work nicely. Leave the lowest frequencies to the sub and the highest to the tweeter. Even though there is no tweeter in the back, I would strongly consider putting a 100 to 500hz bandpass on the rear speakers so they do nothing but reinforce the mid-bass range, which this car can use. With the deepest lows blocked, the response of these drivers should dramatically improve. This would also create a much more defined soundstage at the front of the car, which would be wonderful for the front seats, but suck for the back. Screw `em.

 

[kvndoom]

It`s a five channel amp. Two fronts, two rears, and a subwoofer.
The woofers are allowed to roll off naturally (meaning they are chosen because they don`t do a good job of reproducing high frequencies) and the tweeters have the one cap on each, which is probably there more to protect them from low frequencies than to block low frequencies for sound quality purposes. Everything about this system screams that it should benefit from putting a band pass filter on the woofers. A bandpass filter is just what it sounds like: it allows a selected band of frequency to pass through to the speaker. In this case something like 100 to 3500hz (as a 6db/octave - higher if 12db) should probably work nicely. Leave the lowest frequencies to the sub and the highest to the tweeter. Even though there is no tweeter in the back, I would strongly consider putting a 100 to 500hz bandpass on the rear speakers so they do nothing but reinforce the mid-bass range, which this car can use. With the deepest lows blocked, the response of these drivers should dramatically improve. This would also create a much more defined soundstage at the front of the car, which would be wonderful for the front seats, but suck for the back. Screw `em.

Down the road, probably after the car is paid off, I will definitely invest more into the audio system. Ultimately I will have high-end component speakers in the front, nothing going to the rear doors, and a decent sub for my lows. But right now it just needs to be livable, and I hope the 50 dollar mod that is the heart of this thread does that for me. I may well create a bandpass for the rear doors in the near future, but for now I hope the 3kHz low-pass will suffice. Once I get the mod fully done, I'll have to take a road trip to hear the results. I agree with Bluefish that it doesn't sound bad in stock form, but it doesn't sound good either. It just needs a little bit more presence.

 

[1sty]

There's no way a speaker can "know" what is being sent to it and self-equalize. So unless the driver's side amp is six channels and has a separate speaker output for the woofer and the tweeter, the woofer is getting a full-range signal without a crossover of some sort, even if it is just a lowly single inductor.

I didnt say the speakers "knows" what its getting. Although all speakers do self equalize, if you consider roll off or Fr Response self equalization, not to mention the impedance curve.
What I said:
"Any car with this many speakers often uses internal digital sound processing (DSP) to limit the frequencies each speaker receives."
Hence it would be actively crossed over.
My Xterra actually is a 6 channel amplifier with a separate sub/amp so its very possible I have seen up to 8 channel amps in cars form the factory.

And honestly, that statement almost made it sound like you think Bose knows what they're doing. If they've made such an elaborate system that sounds so sub-par, I'd have to disagree. (lol2)

BOse knows exactly what they are doing, they are selling a name. Its Mazda that has no friggen clue. LAso unless those factory speakers say bose on them, they possibly were not part of the Bose contract. Perhaps only the amp was. You never know with these things as far as spending ALOT of time to make a crappy sounding system.. I'd take bose over Rockford any day.

 

[kvndoom]

If the Mazda6 I had was any indication (it had bose also), it seems that the signal from the head unit is flat, and all the sound processing takes place inside the amp. On that car I went directly from the line-outs to my amp, and then to the Polk's I put in the front doors. With bass and treble set to 0 and just a high-pass of around 125Hz set at the amp, it sounded absolutely wonderful (dual 10" sub in the trunk, of course) with the stock deck.

This project is just directing more of the midrange away from the woofers and into upgraded tweeters. Will it "conflict" with the fixed settings of the blose amp's DSP? Yes, but that doesn't necessarily mean it won't be an improvement. Sound quality will always be subjective to the ear of the beholder. For 50 bucks and a fully reversible mod, I'm willing to try it, since I really don't want to put hundreds into a full aftermarket setup right now.

And yes, Mazda should ditch bose, but they won't, because of brand familiarity. More than anything else, I wish they'd stop packaging it with other things (6-disc changer, moonroof on regular cars, leather seats on MS3) and forcing you to get it as if they were doing you a favor. 4 good speakers and a decent 25wpc amp, with flat response all around, would be leaps and bounds better than this stuff, would cost Mazda less, would be much less painful to upgrade or replace, and I wouldn't care what brand name they slapped on it.

 

[Breezy]

I'm just checking in to say that the mods still sound very sweet and well worth the effort. After a month or two of playing around I'm still right at zero treble, zero bass, and zero fade. And now my wife actually cranks the sounds when we're out and about. It's sounding pretty damn good. Hey guys don't over think it, just do this.

 

[kvndoom]

I'm just checking in to say that the mods still sound very sweet and well worth the effort. After a month or two of playing around I'm still right at zero treble, zero bass, and zero fade. And now my wife actually cranks the sounds when we're out and about. It's sounding pretty damn good. Hey guys don't over think it, just do this.

I finished it yesterday, in fact. I had some poly-fill that I had bought for the Mazda6 that I never used, so I stuffed the doors behind the woofers with it as well. It really does sound a gazillion times better! (eekdance) Those Dayton tweets are out of this world. Over time, I may dabble a bit here and there and make gradual upgrades, but for now it at least sounds like a decent stock system.

 

[Brad]

God this is all greek to me. Basically I'm looking for a link of what to buy and a picture of where to put it and how to put it in. Any chance I could get that?

 

[chief_wiggum]

god this is all greek to me. Basically i'm looking for a link of what to buy and a picture of where to put it and how to put it in. Any chance i could get that?

+1

 

[kvndoom]

(2) Tweeters:

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=275-035

(4) .15mH inductors:

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=266-804

(2) 10uF capacitors:

http://www.parts-express.com//pe/pshowdetl.cfm?&PartNumber=027-428

(2) .10mH inductors: ((optional- if you are going to keep the fader at Front +8, you don't need to bother with these)

http://www.parts-express.com//pe/pshowdetl.cfm?&PartNumber=255-020&DID=7

(2) packs of crimp-on butt connectors:

http://www.radioshack.com/product/index.jsp?productId=2151268

(4) crimp-on male quick-disconnect fittings (I didn't use them, but size the ones you need against your new tweeter)

http://www.radioshack.com/search/index.jsp?kwCatId=&kw=quick-disconnect&origkw=Quick-Disconnect&sr=1

Soldering iron, solder, crimping tool/wire cutter

Electrical tape

You'll have to find a how-to on getting the front door panels off. I didn't take any pictures, but I'll try to be as detailed as possible.

First thing to do is solder two pairs of .15mH coils together in parallel, to make an effective .075mH. This is why you need 4 of them- one soldered pair for each door. Use a bread-bag tie or ty-wrap to keep them together. Set them aside for now.

For both the driver and passenger side, the (+) speaker wire is a solid white, and the (-) is solid gray. This applies for the woofer and tweeter.

Get the door panel off, and look for the wire bundle as shown in this picture. Just make a mental note of where it is for now.

Remove the woofer, and cut the white wire, with at least 2" of wire remaining to the plug that goes to the speaker. Strip about 1/4" insulation off each part of the cut wire.

The reason I listed the mixed pack of butt connectors is because you'll need blue ones for the soldered-together coils. Using the blue butt-connectors, put the coil inline with the white wire you just cut. Wrap your connections with electrical tape. Plug the woofer back in and test to make sure you have a good connection (i.e. you have sound). Now what I did, since I had some poly fill, was stuff the hole in the door behind the woofer. Besides the obvious benefits, it made for a nice cushy place to sit the coil without having to worry about it flopping around. You may choose your own method, but you do want to secure it. Reinstall the woofer and you're done with that part.

Now, that bundle of wires I mentioned before is taped up, with some type of cloth tape. You'll need to cut and peel some of that off to find the (+) junction. What you're looking for is a metal crimp on the white wire where one white wire is crimped to two other white wires. You'll understand when you see it. The single wire coming in is the (+) from the amp. The white wire routed upwards is going to the tweeter. The one routed downwards is going to the woofer. Make sure you note exactly which is which. You want to cut the crimp terminal out completely, leaving 3 loose white wires. Strip each one. Now, twist the wire from the amp together with the wire going to the woofer, and crimp them together in one end of a red butt connector.

What I did was snip the leads from the capacitor down to about 3/4", so that very little was exposed out of the butt connector. The leads on the capacitor are like 2 or 3 inches from the factory, which is way too much for this job.

Okay, so now crimp one end of the capacitor into the connector opposite the two white wires. Then use another butt connector to connect the other end of the capacitor to the remaining loose white wire (which goes to the tweeter). Play some music, turn the treble up, and verify you can hear sound from the tweeter, so that you know your connections are good. Tape up your work, and use some tape to hold the capacitor in place (I taped it to the wire bundle). You're 2/3 done, congratulations.

Remove the window sail. Disconnect the blose tweeter and remove it from the sail. Cut the two wires going to the tweeter connector. To make sure you have enough slack in your wires (I almost didn't), make your cut no more than 1/2 to 3/4 inch from the plug. You'll also see a plastic "tube" that's taped up around the wires. Remove this if you find you need more slack to put the sail back in.

Strip the exposed tweeter wires, and crimp your quick-disconnects onto them. Loosely connect the QD's to the new tweeter just long enough to make sure your connections are good and everything works. Try to contain yourself when you hear the improvement for the first time. Now take the tweeter, and wrap enough rounds of electrical tape (maybe 3) around it to make it fit snugly into the tweeter cutout in the sail panel. Depending on the width of your tape, you may have to trim things up a bit to get it flush. Once you have a good fit, position the tweeter in the sail panel rotated in a way that you will need minimum slack from the wires. You will understand when you see it. Now connect your QD's, keeping polarity in mind, and then put the sail panel back in. If there isn't enough slack in the wires, you may have to un-tape and remove that plastic tube to get some more slack. You may also have to **carefully** bend the tweeter terminals down some to get the sail panel back in. Just take your time and analyze what you need to do to get it done.

Now, put some music on, and play with the bass, balance, and treble controls, to see that everything works. You should notice an EXTREME difference in upper midrange and highs between the modded and unmodded doors.

Put the door back together, and repeat the same process for the other side. The first door took me twice as long, because I was kinda fumbling my way through it. Once I knew what to look for and what to cut/splice/crimp, the second door took less than an hour.

The optional low-pass rear door mod is already explained in detail in this thread. Some people will prefer to fade everything to the front and not bother with the rear speakers at all. It's a matter of preference.

 

[chief_wiggum]

Excellent; thanks!

 

[Brad]

wow, thanks so much!

 

[Breezy]

Good write up KVNDOOM!

 

[meicalnissyen]

blose

great job, and explanation
couple thoughts:
I am assuming you picked 4K to cross
that is clos to the tweets bottom end range, and its power handling may come up short it will very likely be fine, but some people may get them to fail.
simple to replace though.
this one takes a bit more power but may not look as nice

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=279-410

This one costs alot morebut can take all the power easy and has room to go lower if you want to shift more away from the front door you could cross at 3200hz and use a single .10 choke and a 12 cap that would get back some of the cost

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=279-178



also, unless you plan to replace door speakers, it would be much easier to package the xover components neatly and install them under the amp. all the wires are right there. there IS a color code list, but I can't find it right now. save pulling the door panel at least

thinkin out loud

 

[kvndoom]

meicalnissyen, only one positive wire leaves the amp to go into the front door, and it is split from inside the door, so you will have to tap the wires after the split to route to the woofer and tweeter separately. You could alternately put the coil(s) and capacitor inline where the split-crimp was, and probably save a few minutes' time, but the door panel will still have to come off. All this stuff is pretty easy to remove and undo though.

The '09 volume control goes to 63 or so, which is kinda silly (maybe higher numbers create an illusion of higher volume?). My "ideal" setting after playing with it the past few days is ALC2 (3 seems to distort too much regardless of volume), bass -2 (-1 isn't bad), and treble 0. Generally my volume stays in the 40-50 range.

wtf, is time going backwards? how did my post show up before Breezy's, when I was replying to him too?

 

[meicalnissyen]

meicalnissyen, only one positive wire leaves the amp to go into the front door, and it is split from inside the door, so you will have to tap the wires after the split to route to the woofer and tweeter separately. You could alternately put the coil(s) and capacitor inline where the split-crimp was, and probably save a few minutes' time, but the door panel will still have to come off. All this stuff is pretty easy to remove and undo though.

The '09 volume control goes to 63 or so, which is kinda silly (maybe higher numbers create an illusion of higher volume?). My "ideal" setting after playing with it the past few days is ALC2 (3 seems to distort too much regardless of volume), bass -2 (-1 isn't bad), and treble 0. Generally my volume stays in the 40-50 range.

wtf, is time going backwards? how did my post show up before Breezy's, when I was replying to him too?

I was wondering about that while I was typing, and tryng to find the underseat schematic someone posted. well so you could put the caps in the sail and the chokes by the amp, but looks like putting a bandpass xover behind the door is the best way.

I've had door panels off so much it just seems like some never go back quite right

the ms3 appears to be a snap together car, so hopefully it will be snug even after a few on and offs

whaddya think about sliding down to 3200 with the "expensive" tweets?

 

[meicalnissyen]

wtf, is time going backwards? how did my post show up before Breezy's, when I was replying to him too?

he is from ohio,

they are very advanced

 

[kvndoom]

I was wondering about that while I was typing, and tryng to find the underseat schematic someone posted. well so you could put the caps in the sail and the chokes by the amp, but looks like putting a bandpass xover behind the door is the best way.

I've had door panels off so much it just seems like some never go back quite right

the ms3 appears to be a snap together car, so hopefully it will be snug even after a few on and offs

whaddya think about sliding down to 3200 with the "expensive" tweets?

The specs look solid, so if you could get them to fit well, I'd say go for it. The magic of the Dayton's is how easily they fit in the stock cutouts. Without having heard them, I'd still say that the more expensive ones rolling over at 3200 would be good since it takes a little more strain off the poor woofer. If you try it, let us know!