Working with a Bose (circa 1990) system... tearing it all out vs. reusing some parts?

[SadbutTrue 10+ year member]

Hello, I'm fairly new at this, though I have some experience with cars in general (restoring my 66 mustang, keeping my 89 caddy running, which is the car in question... and I'm a Mechanical Engineer from Cal).

Anyway, the stock radio stopped working and I want to use the opportunity to give the 89 Caddy a more modern system with some oomph to it, without breaking the bank. I'm comfortable doing the work myself, and getting parts used and/or from discount merchants.

My first question (many more will follow) concerns how much of the original Bose system I can reuse. While its old, the system didn't sound bad at all when the old casette deck was working. I was considering re-using the front speakers and keeping them wired to the stock amplifier (it is my understanding the Bose system, even back in 89, came amplified stock). I then wanted to install a new head unit, connect it to an amp which would in turn power two new 6x9s (replacing the stockers) and a 12" sub.

I haven'tfigured out what parts exactly I want yet, but does this general plan sound good so far? Or will the Bose amplifier/stock front speakers not work right with a modern head unit? I'm not looking for a competition system, just something to make my alternative rock/metal/hard rock sound good and occasionally make my friends turn up an eyebrow if I play some rap. I figure if I take my time and do the research and work myself, I could do this for ~$500.

Thanks, your input is appreciated.

(and yes, I did read the bcae1.com info.. almost every page... GREAT info but I still have numerous questions)

Click to read more...

 

[SadbutTrue 10+ year member]

ttt anyone?

 

[1991Brougham 10+ year member]

In 1990-92 Cadillac Broughams, the amp is separate from the factory HU but they have to be together to work. When I had my system put in I had all the old stuff gutted out.

If GM kept the same design philosophy in place for your FWD Cadillac, then you'd be best served by junking everything that is factory. The 1985 Sedan DeVille of mine (which has the same dash as a 1989 Cadillac) got a complete redo on it's system and boy did that puppy bark! Using an Alpine cassette deck, Rockford Fosgates in the rear, Alpines up front and a Rockford Fosgate amp gave me some good times 17 years ago.

Rick

 

[GMCJimmyslt2000 10+ year member]

think bout it, those speakers are almost 20 years old, they cant sound that good anymore. I would get a compent set up front and amp them. Run some 6x9s in the back and run them off the aftermarket deck. GEt a nice 12 inch sub in a ported box and a nice amp to power it.

 

[da box king 10+ year member]

Rip it all out, thats what I did, and will always do. It doesn't even sound that good, and the BOSE speakers are cheap. Save yurself the hassle and rewire for new speakers, and get some nice speakers.

 

[Atimm693 10+ year member]

As said, tear everything out and start off on a clean slate.

First off, get a good HU, and some nice fronts, and an amp. If you buy the amps and/or the HU used, you should still have some good money left over to get some good speakers and a sub. Get a good 4 ch amp, channels 1 and 2 for front speakers, and 3+4 bridged for the sub. Pry 150x4 or so.

HU- ~150.00 or so

Amp- ~200.00

Speakers- ~180.00 or so

Installation- 50.00

Not in your budget, but it should work nicely.

AMP

 

[SadbutTrue 10+ year member]

Okay, so chucking everything seems to be the recommended course of action.

So... how would it work to connect the front two speakers directly to the head unit (using the HU's amplified outlets) and then using a 4 channel amp, with 1 channel each for rear 6x9s and 2 channels bridged for a 12" sub?

Any of you guys with old cadillacs remember anything about the speaker specs (like what size the front speakers were, where the amp is located... more i know, the easier it is to rip out)?

 

[ultimate157 5,000+ posts]

Amp the front speakers, not the rear.

 

[Atimm693 10+ year member]

Go to crutchfield.com and enter your car in and it will list the specs.

 

[SadbutTrue 10+ year member]

Amp the front speakers, not the rear.

Alright, dumb question... why front and not rear? It seems like it'd be more useful to amp the larger speakers, plus it'd be easier as far as wiring goes. Not that I'm arguing, just wondering why.

Also, is it likely that the stock alternator will be able to drive all of this or will I need to upgrade that and the battery?

 

[1991Brougham 10+ year member]

The alternator will be fine unless you go into mega-sub territory.

The usual "good" solution to car audio revolves around making the front speakers/front stage the emphasized point. Cadillacs don't have as much to work with in terms of door area to really mount decent speakers, either coaxials or component speakers, due to the largish door consoles that have the armrest, power window/door lock/seat switches, door lights, ashtrays (in some) as well as the door handle itself. The kick panels have an emergency brake pedal on the driver's side, a holding basket on the passenger side and there is not much room behind them either. Thus the speaker placement limitations pretty much dictate going with stock mounting locations and that led me to going with a suboptimal but still workable traditional 4-channel (LF/RF/LR/RR) setup when cost is a factor.

Later on I'll add a sub but it will take plenty of work to port in the bass as Cadillacs are loaded to the gills with sound deadening insulation. I get my bass from the Pioneer 6x9 REV series speakers and they hit pretty good for a 6x9.

The front speakers for my Cadillac are 4x6 and I believe it's the same for the FWD Cadillacs for the years 1985-93. When going with front speakers and a decent amp, you should be looking at plate speakers as those have higher power handling capacity than the standard coax 4x6 types, which usually come in around 30 watts or so. My Boston Acoustics are rated at 80W RMS and most 4-channel amps one would use for good car audio (as opposed to high powered systems) would not be more than that per channel. The Pioneer amp I have puts out 60W (4 channels) and was a great bang for the buck amp at around $125 shipped. Pioneer offers a 75W 4 channel amp but to get the extra measly 15 watts would have required about another $100, so I passed on it. 60W RMS x4 is all you'll need for daily driver quality car audio.

Use eBay to get the amp, 6x9 speakers and your choice of head unit. The 4x6 Boston Acoustics are NOT sold at discount like so many other brands are, so hit up ABT Electronics for those if you want a decent plate speaker. Even having to pay retail for the BA's you should come in at $500 for the equipment ($125 for the amp, $100 for the 6x9's, $130 for the BA's, $145 left for a head unit of your choice).

Now if you want to really get tricky, wait and see if anyone on this forum knows about smallish mids that really handle power and have strong SQ qualities. When combined with the accompanying tweets which can be mounted separately and in a good location for max SQ, you'll be set for a heckuva front stage. The downside is the big expense to install since custom work will be needed for the enclosures, door sound deadening, the tweets and time spent on setting the crossovers (passive) or the amp gains (active/two amp system) for the best sound in your interior. That system will require the sub, amp and box plus all the work needed to port the bass in so you wind up with well-rounded sound. The only things you'll be able to re-use from the 4-channel setup is the amp as the 4x6's and 6x9's will be gone and the headunit if you decide to go with an upgrade to the killer front stage/sub setup.

One thing to think about: You live in a metro area where HD Radio is broadcast. That's a lot of extra stations and extra sound quality to be had, so you may wish to keep HD Radio in mind when purchasing a headunit as this radio setup is only going to get bigger.

Future stuff: Memory sticks requiring USB ports are going to be huge in audio. Who wants to carry a ton of CD's when one little stick will handle a ton of music? iPod connectivity in which the HU controls the iPod is another thing to look at. USB ports also mean massive libraries contained on disc drives. Some people like satellite radio and if you take long trips where good radio is scarce, getting a satellite-capable receiver is worth looking into.

Choose your HU carefully and it will be around a while, able to handle all the new ways of feeding in signals to your audio system.

Unless you're like me and madly in love with older Cadillacs, my final recommend would be to go as cheap as you can. You won't mind letting the system go with the car that way. Then once you see how good "good" is and listen to other systems to know what "better" sounds like, you'll be very informed as to what SQ level to aim for. Some people are happy with "good", some want "better" and then there's those crazy mofos who want the whole oyster...LOL! That's when car audio gets fun but Really Expensive. Just check out the prices from Critical Mass (as an example) to get an idea of what high end gear can hit you for.

Good luck with whatever approach you take SadbutTrue...

Rick

 

[SadbutTrue 10+ year member]

The alternator will be fine unless you go into mega-sub territory.
The usual "good" solution to car audio revolves around making the front speakers/front stage the emphasized point. Cadillacs don't have as much to work with in terms of door area to really mount decent speakers, either coaxials or component speakers, due to the largish door consoles that have the armrest, power window/door lock/seat switches, door lights, ashtrays (in some) as well as the door handle itself. The kick panels have an emergency brake pedal on the driver's side, a holding basket on the passenger side and there is not much room behind them either. Thus the speaker placement limitations pretty much dictate going with stock mounting locations and that led me to going with a suboptimal but still workable traditional 4-channel (LF/RF/LR/RR) setup when cost is a factor.

Later on I'll add a sub but it will take plenty of work to port in the bass as Cadillacs are loaded to the gills with sound deadening insulation. I get my bass from the Pioneer 6x9 REV series speakers and they hit pretty good for a 6x9.

The front speakers for my Cadillac are 4x6 and I believe it's the same for the FWD Cadillacs for the years 1985-93. When going with front speakers and a decent amp, you should be looking at plate speakers as those have higher power handling capacity than the standard coax 4x6 types, which usually come in around 30 watts or so. My Boston Acoustics are rated at 80W RMS and most 4-channel amps one would use for good car audio (as opposed to high powered systems) would not be more than that per channel. The Pioneer amp I have puts out 60W (4 channels) and was a great bang for the buck amp at around $125 shipped. Pioneer offers a 75W 4 channel amp but to get the extra measly 15 watts would have required about another $100, so I passed on it. 60W RMS x4 is all you'll need for daily driver quality car audio.

Use eBay to get the amp, 6x9 speakers and your choice of head unit. The 4x6 Boston Acoustics are NOT sold at discount like so many other brands are, so hit up ABT Electronics for those if you want a decent plate speaker. Even having to pay retail for the BA's you should come in at $500 for the equipment ($125 for the amp, $100 for the 6x9's, $130 for the BA's, $145 left for a head unit of your choice).

Now if you want to really get tricky, wait and see if anyone on this forum knows about smallish mids that really handle power and have strong SQ qualities. When combined with the accompanying tweets which can be mounted separately and in a good location for max SQ, you'll be set for a heckuva front stage. The downside is the big expense to install since custom work will be needed for the enclosures, door sound deadening, the tweets and time spent on setting the crossovers (passive) or the amp gains (active/two amp system) for the best sound in your interior. That system will require the sub, amp and box plus all the work needed to port the bass in so you wind up with well-rounded sound. The only things you'll be able to re-use from the 4-channel setup is the amp as the 4x6's and 6x9's will be gone and the headunit if you decide to go with an upgrade to the killer front stage/sub setup.

One thing to think about: You live in a metro area where HD Radio is broadcast. That's a lot of extra stations and extra sound quality to be had, so you may wish to keep HD Radio in mind when purchasing a headunit as this radio setup is only going to get bigger.

Future stuff: Memory sticks requiring USB ports are going to be huge in audio. Who wants to carry a ton of CD's when one little stick will handle a ton of music? iPod connectivity in which the HU controls the iPod is another thing to look at. USB ports also mean massive libraries contained on disc drives. Some people like satellite radio and if you take long trips where good radio is scarce, getting a satellite-capable receiver is worth looking into.

Choose your HU carefully and it will be around a while, able to handle all the new ways of feeding in signals to your audio system.

Unless you're like me and madly in love with older Cadillacs, my final recommend would be to go as cheap as you can. You won't mind letting the system go with the car that way. Then once you see how good "good" is and listen to other systems to know what "better" sounds like, you'll be very informed as to what SQ level to aim for. Some people are happy with "good", some want "better" and then there's those crazy mofos who want the whole oyster...LOL! That's when car audio gets fun but Really Expensive. Just check out the prices from Critical Mass (as an example) to get an idea of what high end gear can hit you for.

Good luck with whatever approach you take SadbutTrue...

Rick

Wow, I never would have expected such a thorough response... on most forums, the newbies will get a hearty 'get out until you know what your questions even mean' and thats the extent of it. I really appreciate it!

So, is it your opinion the sub is worthless unless I remove the sound deadening between it and my ears (behind the rear sets, in this case)?

Also, since you're familiar with cadillacs (mine is a seville, btw) of this era, where would you suggest placing the amp thats going to power the front and rear speakers? Back in the trunk (Seems like a less than ideal place with a lot of wiring, but its the only place I can think of with the space)? I suppose if I really want a sub I can get a second 2 channel setup to just power it.

In addition, I did use the person aboves advice and looked at the crutchfield link, which implied the front speakers were 6.5" round ones instead of 4x6 (like you said your brougham had). Do you have any idea which is the case? Or is the only way to really know to tear it open and see for myself? Also... the crutchfield site had a pretty long list of chassis types for HUDs that should theoretically fit my dash... is that right? I was sorta under the impression the Caddy's dash would be harder to work with and would require a strange/special HUD chassis.

I definitely plan on getting a HUD that will take HD radio, mp3/mp4/wma files, and be able to hook up to my mp3 player (not an ipod... are most hookups just straight usb or ipod specific?). I was considering an inexpensive lcd setup with a tv tuner/dvd capability... would come in handy for football season (could watch highlights in the parking lot while tailgating, plus dvds can hold a load of mp3s), but the $400 price tag for more brand name setups seems to kill it a bit for me.

Finally, and this might be useless cause no one will read this long of a post.. but a few general questions:

1) If i make my own enclosure for a sub, what wood should I go with? Any pointers beyond how big to make the interior space as per online calculators?

2) Where do you guys get your wires and fuses? Should I be getting anything particularly special or is an 8 gauge wire an 8 gauge wire regardless of where you get it?

3) When you say 'porting in the bass' do you essentially just mean removing sound deadening between the speaker and the listener? Or is it more complicated than that?

4) Finally, the biggest concern I have remaining from the bcae1.com site is that I want to make sure I match the speaker impedences correctly (it warns multiple times that you don't want a speaker with too little resistance for the hud/amp). Are there any rules of thumb for this? It seems like there'd be an optimum tradeoff between the two, but I'm not sure what determines where that optimum point is

Thanks again!

 

[SadbutTrue 10+ year member]

One other question, in addition to the ones above.

Also.. I need a new antenna anyway (long, somewhat amusing story). Short version... someone broke my old antenna off at the base. My original antenna was a power unit. I don't really feel like I need anything like that. A cheap standard style one would work, assuming it would be easy to install in place of the old one

Does anyone know where I could get an antenna that woudl be relatively easy to put in the place of (whats left of) my current one? Also, do I need a special antenna for HD radio and/or TV tuning (if I were to get a HUD with an LCD/dvd/etc)?

 

[Atimm693 10+ year member]

1. Volume will depend on what sub you choose, tuning mid to low 30s.

2.Depending on the power you will be running you'll need either an 8 or 4 guage kit. http://www.knukonceptz.com should fit the bill. Stay away from cheap shit.

3.On a lot of "luxury" type cars i see people that will fold the seats down, remove rear deck 6x9s, or cut a hole in the rear deck to let the bass through the trunk into the cabin.

4.Most speakers are 4 ohms, if they are 2 ohms most amps should take that non-bridged. Check what the amp is stable down to and what the speakers are. Generally subs are dual or single 2 or 4 ohms. DVC(dual voice coil) has a couple wiring options, (DVC 4=8 or 2 ohms, Dual 2=1 or 4 ohms etc.)

 

[1991Brougham 10+ year member]

Cadillacs are full of sound-deadening material so you'd better port in the sound to get the sub to do it's job.

Eyeball the speaker through the grill to see if you can approximate what you have. You can refer to the factory service manual if you want to be dead nuts sure. I always buy service manuals for my cars and they sure help mechanics as well as installers.

Crutchfield and other sites said the Pioneer DIN 1.5 worked in my Brougham. My installer gave it a good college try and it didn't fit, so I had to sell it off at a small loss, then go with the Alpine HU/EQ setup I have. I'm happy the Alpine stuff turned out so well so it's not all Bad News...LOL!

I have no familiarity with the Seville/Eldorado so you're going to have to go like I did, by using your best guess and if the install doesn't work out, get something else in regards to the HU. I'm guessing they are DIN 1.5 openings and that should offer some options for HU's.

Regarding MP3 and iPod...some units have a generic input and you can feed anything you like through there. The Alpine I have is specifically set up for iPods and the HU controls the iPod. The newest HU's by Alpine have both iPod and USB capability but no CD player. Just add a changer if you go that route. Personally I'd rather stuff an iPod in the glove box than carry around a ton of CD's, whether it's in my 12-disc cartridges or in single form. I'm also looking forward to a HU upgrade so I can use my memory sticks, which offer the same memory for much less than an iPod but file management is not as good.

Alpine HU's can accept modules for HD Radio and satellite radio. Satellite radio has almost all major college and all the NFL games on it, so why worry about TV? TV is going to change REAL soon as the old channels get replaced by new ones, so don't worry about TV in your vehicle's HU right now. Check the CES 2009 for new TV stuff as used in mobile apps as that's the year we all have to deal with on-the-air signals changing over to the new frequencies.

Sub boxes: I'd just buy a commercially available box and stuff it with some fibrous filling like one would find at a fabric store. It's not like you have to hit the mark with a killer sub unless you're trying for max SPL in some audio showdown...LOL!

I have my equipment professionally installed. Let them wrestle with the alligators is my take...LOL! I've got enough on my plate without screwing around with a car and I don't have a garage or a ton of tools. On the other hand if you have everything you need to do the job as well as the time, go for it!

Porting is going to be custom so experiment! Each car has it's own peculiarities. I have no idea of how much you'll need to do vs how much your sub puts out. When it's time to have mine ported I'll have them drill holes in the back deck, through the insulation and generally go for the overkill approach since I can always dial back the sub amp's output with the EQ. It will be labor intensive for the installer but my guys like a challenge and always deliver good service.

The shop provides the whole shebang for wires and fuses. They do a great job of installation and have over 2 decades of experience doing this, so I let 'em put in whatever they like. If there's problems later on, then it's on them but so far no problems have occurred on the wiring end. If anything, it's an amazingly clean install.

My trunk has panels on each side that have enough room for the amps. I don't know what the Seville/Eldorado trunk looks like so you'll have to see if the "stealth" option is there like it was for me on the Brougham. I'll have the sub amp located on the driver's side behind that panel with the sub box facing forward right next to it while the 4-channel amp is currently behind the passenger side panel. With the sub box being the same color gray as my trunk's carpeting, there's no bling to attract the eye to a casual passerby plus the front-firing sub will not be seen at all. I like that

Now if you have 6.5 round speakers up front, I'm guessing you have them in the doors since I've never heard of front dash mount 6.5's before. If so, you are in for a great sound and should look to up your budget for a quality component set, an amp for them, then remove the rear speakers to port in the sub's output. Your SQ will eat mine for lunch, I guarantee it! Just be sure to find someone who can put the proper sound-deadening material in the doors to max out the performance of the component speakers. The tweets are small enough to mount on the pillar or close to the front top of the door panel.

Some people go with replacement power antennas, some have them rebuilt and some put in various kinds of manual antennas. The previous owner replaced the original on mine with another power antenna for a cost of under $200 parts and labor, so if you like power antennas (I do) and have a good shop that knows how to handle them in Cadillacs, which can be tricky for some models according to the Cadillac forum I read, then keep the power antenna unit. I regularly clean and lube mine as per the owner's manual and have had no problem with it.

Hopefully I covered all the questions you brought up. You'll make a good first stab at a system, then you'll see what you could do different. That is when the credit card is your friend...LOL! Your system will be as individual as your car and your requirements are. This is not Factory Radio One-Size-Fits-All after all! There's so much tech out there it's unbelieveable and you're in for an ever-evolving system as new things come down the pike. The one thing that will be a fundamental building block will be the speakers and amps as you can run newer HU's and modules over the years to accomodate new ways to do things. Get that foundation right and you'll be good to go for many years.

Rick