Guide How-To Fix for Bose. Photo Essay

HOW-TO install amplifier and speakers in GT Photo Essay

Greetings,
after much investigation (reading all the BLOSE posts) and procrastination and credit card abuse (see bose signal processing thread)
I have finished my install(dance)
Goals Being
1 Flat and clean response 20-20K
2 strong front stage
3 reduction in door buzz and hum
4 increased power
5 dead stock appearance
background; I like audio, I have a fair understanding of what makes it pleasing to human ears, and what factors come into play in the home vs car environments.

step 1

figure out why the stock sound is bad
educated guess : low power system with odd ball circuitry in the stock amp
replacement of stock HU uneeded unless VERY clean CD audio OR very good FM reception is needed. stock HU is ess flat so JL cleansweep or eq will not produce much bang for the buck

Dash was never touched in this install

SO
pull the door panels off

this has been covered, but I want to make some points.
(If you are an audiophile, and want to pick this apart, PM me. I am trying to dumb down, sugarcoat, and analogify a complicated subject for the majority)

a speaker makes sound when the cone moves. when it moves forward, a positive wave comes off the front, while simultaneously a negative wave leaves the rear.
the enclosure exists to keep the rear from cancelling the front. this is very freq dependent because the physical length of the wave is the cancelation factor
three basic enclosures exist
infinite baffle ) a board with a mounting hole prevents cancelation down to wavelengths equal to the distance around the edge of the board

bass reflex ) a sealed box. rear of the cone is never heard

ported) box with a tube releasing energy from the rear of the cone . dia and lenght of tube in relationship to box size influence the freq response

car doors are of the bass reflex style, except when the window is roled down, then there is a 1/4 x 20 inch port / whistle

when you make an enclosure, one main goal is to build a nice stiff sealed box. This prevents the walls of the box from acting as passive radiators of the rear wave, and stray squeks and whistles from escaping gaps and holes.

standing waves. ever see the shot of the SR-71 blackbird , with the stripes in the exhaust ?? standing waves bad, make some areas of the room or encloseure "boomy" best shape for the enclosure is a sphere, kills all the waves.

SO, with that brief background, lets look at the MS3 speaker enclosures
Now, I have yet to figure out how to embed a photo, and no one has told me, so, sort thru the attachments (moon)

pic1

this is the inside of our door
there is NOTHING stiff or sealed about it. the folks at Cerwin-vega do not make sub enclosures from thin sheetmetal and injection molded plastic
it is the farthest thing from ideal.



SO enough ranting, lets deal with what we got!


MITIGATION
nothing is perfect and bad things can be made better

pic 2 and 3
deaden vibration and damp waves

now we have a crappy enclosure that at least does not buzz and vibrate like it did before. we can now slam it with rear waves, without a ton of passive radiation and stray non-musical sounds


we move on.

front stage
Humans are VERY sensitive to the physical location of sound, and much more so when the freq is higher, the phase of the sound matters most with lower freq
this is why the rear door speakers are not much help, they are behind you. Why tweets in the rear sails are useless, they distract your brain terribly

set it up like your home stereo. a pair, of well balanced full range speakers equidistant, and level with your ears. Placed in a room with non reflective walls.

ha ha

Oops, we are in a car. front speakers by our feet. left tweet 18 inches away, right is 4 feet away a large amount of the surface is glass, volume is littered with reflective/absorbitive objects

what to do?

use the tweets as much as you can. (lower xover point) this raises the frontstage up to be more level with your ears. use the rears at a lower freq and lower volume, essentially just a bit of fill

this requires a real good tweeter that can take some power, we added power with the new amp, AND funneled more of the total portion of load to it by lowering the xover point
pic4,5,6,7.8

part2

rest of tweet pics
ok now, punch up the front door with the majority of the power handling capability and clean tight reproduction

IE spend money
next pics
this is a nice unit, there are others
use componets, avoid coaxials, they put high freqs out down low near your feet

part 3

the mounting
the front used a smaller dia driver, so I made a plate to adapt. the rear I used a 7 inch driver and only need to fill in a small area
you just need a tight mount and caulk the gaps.
depths are listed at like 3.25 and 3.75 f and r, main issue fitment wise, is the door panel has a plastic ridge wich may hit the surround just shave it off with a sharp knife. last pic I illistrate the tweet wire coming out and runnin up toward the sail

part 4

next pic shows the crossovers
these are the taped up things

you may buy a component set with xovers all nice and made up. use them, they will likely serve you well
I used a 12db 2nd order

what does that mean??
well, we want to recreate what is on the album (CD kids)
it has freqs from 20hz to 20kHz
no driver can reproduce the whole spectrum by itself, so we build speakers with 2 or more drivers in an attempt to create something that will produce all freqs evenly without spikes in the loudness of any particular band of freqs.

this is very hard (expensive) to do
drivers have sweet spots that do certain freqs better than others
you pick drivers that complement each other, then filter the freqs going to each one with a crossover which sets the freq point where one driver CROSSES OVER to the next.

hence the term

this is not a light switch, it is a progressive damping out
http://ccs.exl.info/calc_cr.html
read, then read more


I reccomend certain adjuncts to understanding this.
first, you need a reason to exist...... pic 2
I capped the rears at 1800, and in the front, crossed to the tweets at 2600
Using the amp, I blocked the front door at 600, and the rear at 125
the sub goes up to 120

this means that the front door does not have to participate much in anything under 500hz
this action GREATLY reduces the need for dymat etc

read the above para again.......

last 2 pics show the inside of rear door panel, and the metra connector to fit the stock harness best buy install bay is where I got it

all these numerical vals are mushy rollover areas NOT exact transfer spots

part5

allright, so what feeds the crossovers??

clean flat signal (with the exception of the amps internal xovr) from a HIGH quality amp which amplifies.

not distorts, adds, subtracts, whines, hums, etc

it must be fed CLEAN signal, it will amplify every thing (crap in, Lotsa crap out
located in an area with air movement since it is not 100% efficient, it gets hot
it gets three sets of wires runnig in and out

power wires
input signal
speaker level output

speaker wire is pretty imune to screwup

run the input (rca from the HU) and power(12+ from the radio freq generating alternator) parallel to each other, close enough,and for enough distance, and your input will act like a little antenna and infuse itself with alternator sounds which get amplified

OH Joy

mazda avoided this.

I took signal and power from the mazda connector, and made no parallel paths with the very short pieces I added.

I have NO whine.
I am happy
run fat ass 4 g amp wire and rca from the back of a aftermarket HU at your own risk


I used the connetor from the bose amp so I could avoid making joints on the 3 inches of wire sticking out of the carpet. I did my soldering on the kitchen counter with good light and a nice chair. the car it self remains unmodified, only the bose amp was injured in this process.

spca (Society for the Prevention of Cruelty to Amplifiers 1-800-111-2233

part6

Physical mounting

per one of my parameters

Dead stock appearance

the new amp goes where the old amp was

I used the 2 convienent studs mazda provided and made a couple brackets
you can see the red power wire if you look for it, and the mazda cable for the seat position sensor ( friggin car knows where I sit)! sticks out a bit

this took some time and I want to thank my two assistants for keeping the area free of lizards so I could work

part7

THE SUB

I originally bought a blaupunkt sub that would fit under the seat where the blose rich bass system goes.
this piece of crap wasted alot of my time and 80 bux
not happy with that

I bought a basslink from infinity to replace it, it is well rated, I have used it for a day now and I agree. and flexible between the gain , Db, and cutoff, you can get it where you want it.

it is a high value unit


the problem

I screwed up when I researched the basslink
it will not meet a parameter
fails the stock appearance clause

so I improvised

I have two kids
15 and 17
it is exceedingly rare when I need to have 4 people in the car
I am Tall, and the seat (throne, friggin bus height seating) is always all the way back (except autoX, 2-3clicks up)

I value hatchspace more than rear seat space. shopping etc

besides, a sub in the hatch, how do you hear that???
flip the seat down? fail
pound sound thru the hatch cover?... fail

SOOO
I hid the wires (power) along the left side and signal, under the mat, then seat. NO whine
then using the convienence of the standard 120v grounded connectors
three conductors...... 12+, ground, remote12v
I made a quick disconnect sub setup sitting on the rear seat behind me.

circled area is all that will show when removed, small female half of the connector

sounds GREAT
permits seating 2 passengers anytime
removes to store in the hatch in less than 30 sec


The last 2 shots are of the stock bose drivers
the four doors are identical

they are NOT like all these shots we have seen of sport owners drivers
they are NOT 6x8 like crutchfield proclaims, though the mount likely is
they look nice, I think they would take 20-30 RMS and do 100-5k very well.

I may use them to make a tiny guitar setup with a 25 watt tube amp I have laying around

the tweets, of course are a joke, and the single worst part of the system, the second being the circuitry in the amp which is biased to protect them.


I have killed alot of my day here, time to wrap it up!

I sincerely hope this helps many others to improve the audio with minimal effort(yippy)

one part remains

part 8

the results

I have not borrowed a meter, but the sweep test on my memorex cd sounds pretty flat
I will be tweaking with the amp cutoffs, try to get it as flat as possible

1 pic left

initial impression

I hate to break it to you, but you got the original Basslink, the 200w one. I had that in my last car, it was OK (to be fair, it was in the trunk of a sedan). I have the Basslink II (250w, upgradeable amp) mounted upright in the hatch bungie-corded to the child seat latch on the 40% side of the 60/40 rear seat.

I haven't had much time to tinker with it, and right now I'm getting the signal from the rear pre-amp channels. Tomorrow I'm going to tap into the front pre-amps and see if there's any difference. But as of now, I'm liking the low-range oomph and minimal loss of hatch space.

Kain said:

I hate to break it to you, but you got the original Basslink, the 200w one. I had that in my last car, it was OK (to be fair, it was in the trunk of a sedan). I have the Basslink II (250w, upgradeable amp) mounted upright in the hatch bungie-corded to the child seat latch on the 40% side of the 60/40 rear seat.

I haven't had much time to tinker with it, and right now I'm getting the signal from the rear pre-amp channels. Tomorrow I'm going to tap into the front pre-amps and see if there's any difference. But as of now, I'm liking the low-range oomph and minimal loss of hatch space.

Click to expand...

Thanks
basslink 1
I misspoke
I have the gain down to 50-70% so, glad I don't need the extra

Nice work on the install. I've never seen anyone use the stock amp connector before, lol.

So this continues to support the theory that the HU and pre-amp wiring is more than sufficient for a stealth install - without the need for a complex signal converter. Mine is going in early next year, so I'll be sure to post accordingly.

BTW, you might consider linking this from the Electronics Forum since this won't get a lot of traffic. (2thumbs)

What gauge is the factory power wire? Just curious how much current it can handle. I'm still debating whether I want to get an amplified sub or just run a passive sub off channels 3 & 4 on my amp (I did this on the Mazda6) and not use the rear speakers at all.

Quick question for ya- does the Blose sub in the 3 have its own amp (line-level signal coming in) or does the main amp drive it too? I remember on the 6, there was another tiny amp along with the "bass" driver in the rear of the car.

Big thumbs up for all your work and effort!

kvndoom said:

What gauge is the factory power wire? Just curious how much current it can handle. I'm still debating whether I want to get an amplified sub or just run a passive sub off channels 3 & 4 on my amp (I did this on the Mazda6) and not use the rear speakers at all.

Quick question for ya- does the Blose sub in the 3 have its own amp (line-level signal coming in) or does the main amp drive it too? I remember on the 6, there was another tiny amp along with the "bass" driver in the rear of the car.

Big thumbs up for all your work and effort!

Click to expand...

the "rich bass system" is just a nice tiny, isobaric sub not self powered. Interestingly, its speaker wires come from the power/groung section of the amp connector, separate from the signal in/speaker out section.

You would not be wrong to run without the rear doors, technically very correct. From a front stage perspective. BUT you will be asking your front doors to run down to under 200 at least, likely to 125 to avoid a hole. the front door internal volume is way to big for a 6.5 driver, and as the only woofer running between 125 and 1k , it will have to hump it pretty hard without much support from an enclosure when you turn it up. You will also feel the door vibrate, and likely have a buzz or rattle to deal with. The rear door is smaller, and much easier to deaden, and stuff so it is a better woofer enclosure.

Guage? dunno, 10 I'd guess

I did cheat, when I was trying to run the blaupunkt powered sub under the Pass seat, I tapped this fat ass pink wire (just with 12 g though)and ran it down under the pass seat.

when I installed the main amp, I figgured I'd help it out and snuck the 12g over the hump under the center console. I left the carpet intacct and used black wire for the run, its visible, but you really have to look to see it. so, it is fed with the stock wire, and a 8-9 ft run of 12g

I have not heard my system starve for power, but this would be a very ideal place to use a cap, and I will likely get one

Design said:

Nice work on the install. I've never seen anyone use the stock amp connector before, lol.

So this continues to support the theory that the HU and pre-amp wiring is more than sufficient for a stealth install - without the need for a complex signal converter. Mine is going in early next year, so I'll be sure to post accordingly.

BTW, you might consider linking this from the Electronics Forum since this won't get a lot of traffic. (2thumbs)

Click to expand...

I can't even embed a photo, and he wants me to try to do a link

OK, but if the server crashes, its on you

bump to the top for OP

essay update

oh boy,

well. here we go to further the cause, I found some tweets that will take 100 rms and I can x em at 1600

snug in several ways, I have a third order setup to chop it off harder and they present 1.9 ohm to the amp when run in parrallel.

also, I think the sail panel pop connector is not made for a pound of tweet magnet
epoxy should help

I believe I have elevated my front stage

speaking of front, and stage



oh yeah

nice pic for a sammy a737

Well, the audio is mostly greek to me, but you do have excellent taste when it comes to brew (he says as he downs the last of his Dunkelweizen). OT, I know, but I finally had a Sammie that I couldn't stand, and I must warn all Sam Adams lovers who have not yet experienced it. It's their most expensive brew - unlabeled (at least no paper label), called Triple Bock, in a dark blue bottle. 5 bucks for a 9 ounce bottle. DO NOT try this stuff - you might as well go buy some Teriyaki sauce and drink that - it would taste the same and be a lot cheaper

I took one swig and ended up using it to marinate my steak.

khoney said:

Well, the audio is mostly greek to me, but you do have excellent taste when it comes to brew (he says as he downs the last of his Dunkelweizen). OT, I know, but I finally had a Sammie that I couldn't stand, and I must warn all Sam Adams lovers who have not yet experienced it. It's their most expensive brew - unlabeled (at least no paper label), called Triple Bock, in a dark blue bottle. 5 bucks for a 9 ounce bottle. DO NOT try this stuff - you might as well go buy some Teriyaki sauce and drink that - it would taste the same and be a lot cheaper

I took one swig and ended up using it to marinate my steak.

Click to expand...

beer

try weyerbachers "SIMCOE"

since you like weiss (yuck( hahaha
take 1/2 ~ 1 tsp of trappist preserves and stir slowly into a nice weiss

tastes just like toast and jelly
the true breakfast of champions


oh, since my PIECE OF CRAP CANON S2 IS

died with the "stuck iris black screen of reath.

canon sux worse than mazda NA

I cannot update the last part of the tweet upgrade

but if someone local with a blose wants to pop there fav CD into my system and report back to the group...............

Thanks for trying to shed a little more light on something that many members find difficult.
I have one issue though, how do you feel that a big ugly sub on the seat is stealth? I realize it comes out, but then you have half a system.
I personally chose the jack sub option pumping over 300 watts to that poor little 8". This setup does not pound like the two tens in my truck, but in conjunction with the stock sub, (I left in), makes some tight bass and qualifies as stealth. Long story short, the stock system, (Bose or not) is pathetic for a car this new and requires extensive mods to make an audiofile happy.
I know it's a lot of car for the money, but if you're going to offer an audio upgrade it should include more than just decals.
Keep the ideas coming though.

NiteRunner said:

Thanks for trying to shed a little more light on something that many members find difficult.
I have one issue though, how do you feel that a big ugly sub on the seat is stealth? I realize it comes out, but then you have half a system.
I personally chose the jack sub option pumping over 300 watts to that poor little 8". This setup does not pound like the two tens in my truck, but in conjunction with the stock sub, (I left in), makes some tight bass and qualifies as stealth. Long story short, the stock system, (Bose or not) is pathetic for a car this new and requires extensive mods to make an audiofile happy.
I know it's a lot of car for the money, but if you're going to offer an audio upgrade it should include more than just decals.
Keep the ideas coming though.

Click to expand...

I know the sub is not stealthy, but it was all I could do with it when it became apparent it was not going to fit where the rich bass piggy bank resides.

The jack box is my alternate choice, for sure, but I just do not see getting enough volume to make a correct enclosure and stay flush. Though sticking out there would be minimally intrusive.

Strick has a very nice ilooking nstall, but it reduces the hatch to a couple bags of groceries, that could still fall onto the sub.

Most of the time, I have a rewarding audio experience, on rare occasions, I have both seats folded all the way down, and a bunch of crap laid in the hatch. when that happens, I still have the rear doors runnin strong down to 150Hz.

If I could get the jack box volume to tune to a f3 of say, 25, or even 30 would be tolerable I would go that route.

I have a nice black shroud over the basslink now (nana)