TrailBlazer Model Year vs. In-Door Speakers

[SEMIJim]

Hi There,

My wife's 2003 TrailBlazer is scheduled for the boneyard. Frame rusted though and cracked. I have a 2007 TrailBlazer. The front and rear driver's side door speakers are dead on mine. Will the speakers from her truck fit? And match the right side in my truck? I have the Bose sound system. Her old truck does not.

Thanks,
Jim

 

[littleblazer]

Bose speakers are oddball. Front is almost 8 and rear is like 5. The base is 6.5 and 5.25. You can make them fit...

 

[SEMIJim]

Thanks for the follow-up.

Odd, because I had a local car audio place quote installing a new radio, a backup camera and replace both rear speakers. (I thought at the time only the back left speaker was out.) He quoted Alpine SPS-610s, which are a 6¾" speaker.

I just assumed the fronts were the same.

ETA: Just checked Crutchfield. They say both front and rears are 5¼"!

ETA2: But they list a coaxial as possible for the rear, but, component-only for the front?!?!

Correction the 3rd: So it seems the fronts are 6½ but the rears are 5¼. What threw me is the Alpine SPS-610 won't fit the front because the tweeter protrudes too far.

Who ever knew speakers, speakers, off all things, could be so flippin' tricky?

Jim

 

[Sparky]

Basic audio is 6.5/6.75 front and rear. At least, on my 2002 the rear speakers were the same as the front.

I know Bose has a weird rear speaker size.

 

[SEMIJim]

I cannot imagine why GM would have done that that way. Talk about making things more difficult than they need be.

The bigger problem now is the fronts are supposed to be just woofers. Can't buy just 6½" woofers. Oh no. Nope: Gotta buy component setups, which are st00pid expen$ive and there's nothing wrong with my dash-top speakers.

Grrr...

 

[littleblazer]

6.5 won't fit anyway. Ask me how I know... check out parts express they have a decent selection to choose from as far as individual woofers.

 

[SEMIJim]

6.5 won't fit anyway. Ask me how I know...

Waitaminute. You're saying 6½" woofers will not it in the front? Crutchfield, who allegedly are experts, claim they will. (With an adaptor bracket. Dunno what that's about.)

*sigh*...

check out parts express they have a decent selection to choose from as far as individual woofers.

I was actually hoping to obtain whatever I needed from Amazon.

Thanks,
Jim

 

[Sparky]

I think technically they're 6.75"

Unless you have Bose, your front speakers can be whatever. I'd use coax 2 or 3 way if yours are shot. I never replaced my fronts, they were fine the entire time I had the vehicle. The rears were another story. I had 6" speakers which I got to fit in there OK, but they should have been 6.5".

 

[SEMIJim]

I think technically they're 6.75"

Unless you have Bose, your front speakers can be whatever.

Yeah, but, I do have Bose.

The speakers I've been looking at on Crutchfield are mostly listed as 6½" or 6¾". I suppose that may be what the adaptor bracket is for?

And the backs are apparently 5½".

Jim

 

[Sparky]

Ohhhh right sorry I missed that.

 

[littleblazer]

With a bracket it should fit. Missed that part. The Bose woofers are large.

 

[Matt]

In the "Bose" system with the amp, the fronts are 8" midbass, the tweeters are 2". Both fronts are 2ohms. The rears are 5 1/4" 4ohms but you can use 6.5" speakers in their place.

 

[SEMIJim]

I think I'm GTG. Stopped by a car audio place on the way home that I'd had quote an upgrade. Explained the truck was dying a rust death and I couldn't justify spending Big Bucks on the upgrade. Asked about speakers. Long story short: Walked out with a Bose woofer that he'd taken out of another upgrade: $40, and a pair of Alpine 6½" coaxials for the rear for $65. He even threw in the properly-sized stacon connectors for the Alpine speakers He warrants all the speakers for a year--incl. the used Bose woofer.

Those Bose woofers are an interesting design. Can't say as I've seen anything like that before.

 

[littleblazer]

The coil is just on the front instead of the back. Not too scary looking but the rear spider is cool.

 

[SEMIJim]

*sigh* I guess the previous owner really went to town. I could have known, by the fact that there was obviously an amp fastened to the back of the back seats at some time and the right rear speaker was found to be entirely missing when I bought the truck. What's behind the grills in the front is most definitely not 8" mid-bass woofers. Looks like oval triaxials of some kind.

So, after I get the driver's side door panel off and confirm that an 8" woofer really does go in there, I guess I'll go hunting for another.

 

[SEMIJim]

For the love of...

Here's what was wrong with the left rear speaker:

In addition to the one wire just barely sitting on the back of the barrel of the one stacon terminal connector, both speaker terminals were badly rusted. That might explain why, before it died completely, it would occasionally go out and a quick blast of increased volume would temporarily bring it back.

My wife (more patience and smaller hands) cleaned up the speaker terminals with 800 grit wet/dry sandpaper while I re-terminated those wires. Violà! It works.

Only reason I didn't rip it all out and re-do it properly is the speaker doesn't match the (factory) speaker on the passenger side, so I may be back in there, soon, and replace both.

Btw: It is a 5½" mounting. How one would ever get a 6½" speaker in there is a mystery to me.

Now please 'splain this mystery: After I repaired that speaker's connections and got it going again, the front left speaker magically started working again.

Threw Fleetwood Mac's Rhiannon on and it sounded great. Maybe I should just leave it be, mis-matched rear speakers and all...

 

[Reprise]

After seeing your tribulations / pessimism in your other post, I'm inclined to agree with you - leave it be, and enjoy one little victory.

One thing I might do before sealing everything back up is to check the impedance on the speakers, since they're mismatched - make sure they're both 4ohm. If not, I'd match the impedance on both - your head unit will thank you in the long run, IMO.

 

[SEMIJim]

After seeing your tribulations / pessimism in your other post, I'm inclined to agree with you - leave it be, and enjoy one little victory.

Apologize for the negativity, but, it's just been one disappointment-after-the-other, with this truck, lately.

One thing I might do before sealing everything back up is to check the impedance on the speakers, since they're mismatched - make sure they're both 4ohm. If not, I'd match the impedance on both - your head unit will thank you in the long run, IMO.

Too late. It's done. It works and it sounds pretty good. I'm inclined to leave it be.

One of the aforementioned disappointments was the discovery, early last week, of small bubbles in the paint on passenger side front door. Means it's rusting from the inside, out. Cannot be stopped, nor reasonably or effectively mitigated. I won't bore y'all with the details. Long story short: That's the death knell for it.

 

[SEMIJim]

Okay, rolling the dice and giving this one last try. Just ordered a pair of Alpine 5¼ coaxials for the rear from Amazon and a pair of Bose woofers for the front off eBay.

My luck's got to turn eventually, right?

 

[SEMIJim]

Update:

• $100 worth of speakers
• $20 or so for various fasteners and adhesives
• Stacon terminals, heat shrink and 3M vinyl tape from stock
  
• A reinforcement fabricated from some on-hand sheet metal
  
• Several hours of swearing at previous owner
• And a hole in my finger ...

... later: It's done!

The adhesives and fab'd reinforcement were to repair broken stuff that fastens the door panels to the doors. The fasteners (screws) were for the Bose woofers. (They came with the plastic bit, which is a good thing, cuz the PO had removed them.) The hole in my finger is for forgetting it's a Bad Idea to have bits of your body on the other side of a work piece you're drilling. (I think I'm up-to-date on my tetanus shot.)

The Alpine SPS-510 5¼" coaxials, despite all the great reviews, are kind of underwhelming. At least to my ear and as heard from the front seat. I'll have to try the back seat.

Those original Bose woofers are unbelievable. The increase in bass response over the 6x9 three-way speakers the previous owner had put in cannot be overstated. Night and day.

Was it worth it? Damn betcha it was! Hole in my left index finger and all. Sound used to be kind of harsh and washed-out. Now it sounds fairly balanced and has much more bottom.

 

[Mooseman]

A lot of people don't like the Bose setup but it's actually pretty good, especially with an aftermarket HU. I miss that in my LS. Too much work to retrofit though.

 

[SEMIJim]

A lot of people don't like the Bose setup but it's actually pretty good,

Sounds pretty good to me. My wife, too. The car audio place I've been talking to thinks pretty highly of them. In fact: One of the owner's two cars has the same Bose system in it and he sees no need to replace it. This is a guy that gets the components at cost.

especially with an aftermarket HU.

I was wondering about that. I'm still toying with the idea of upgrading that bit. Say I wanted to install a Pioneer AVH-X391BHS, which, according to Crutchfield, will "drop right in": Do the speakers work the same?

 

[Mooseman]

You need an adapter/interface to connect any aftermarket HU to the stock wiring, especially to get the Bose amp working. Biggest improvement is the ability to better adjust frequencies via a real equalizer if the HU has one. I especially enjoy my Android HU's.

 

[Matt]

I have the AVH-X2800BS and it was pretty much plug and play, except as Moose said, an adapter for the amp. Also a micro bypass if you want the DVD to play without using the park brake.

 

[Mooseman]

A micro bypass? I just ground the park brake wire.

 

[SEMIJim]

I presume that if I order via Crutchfield, the "installation package" they recommend will have the needed adaptor/interface/what-have-you?

 

[Mooseman]

No necessarily, especially with Bose systems. I use PAC adapters. I used the RP4-GM11 in the Saab and 02 TB. Only thing it doesn't retain is OnStar.

Metra is garbage, failing in short order. Have heard that Scosche can mess up the data bus.

 

[SEMIJim]

No necessarily, especially with Bose systems. I use PAC adapters. I used the RP4-GM11 in the Saab and 02 TB. Only thing it doesn't retain is OnStar.

Metra is garbage, failing in short order. Have heard that Scosche can mess up the data bus.

Thanks for the info.

Looks like this is what I'd need? AC OS-2C BOSE OnStar Radio Replacement Interface for General Motors with Bose System

The radio Matt mentioned looks pretty good, too, and nearly $100 less than the AVH-X391BHS at Crutchfield. Hmmm...

 

[Mooseman]

That would work except that it uses the HU's speaker outputs instead of the pre-amp RCA out. I had that interface and the sound was not as good. You want to use the pre-amp for a cleaner sound and less distortion.

 

[Matt]

A micro bypass? I just ground the park brake wire.

Yeah, the new Pioneer HU's don't work like that now, they need a pulsed signal to work. Apparently Pioneer did some programming and took the ground wire workaround out.

 

[SEMIJim]

That would work except that it uses the HU's speaker outputs instead of the pre-amp RCA out. I had that interface and the sound was not as good. You want to use the pre-amp for a cleaner sound and less distortion.

So I went to PAC's site and tried to figure out what would work. Only thing that looked clearly right was a PAC OS-2X, which, apparently, works for both Bose and non-Bose systems, contains everything and the kitchen sink, and retails for $170!

Doesn't say anything about amplifier output levels.

I got enough projects on my hands atm. I think I might just keep the original radio, as "uninspiring" as it is

 

[Sparky]

My $50 Metra unit worked fine for over 5 years. It didn't have Bose or Onstar support though (my truck had neither).

I still have it kicking around here someplace, never did anything with it.

 

[Mooseman]

My $50 Metra unit worked fine for over 5 years. It didn't have Bose or Onstar support though (my truck had neither).

It's probably a much simpler circuit than those for Bose. I had two (or was it three?) fail on me in exactly the same circumstances when the battery was disconnected. No sound and the radio would not shut off at all.

The PAC OS-2X also uses the post amp (speaker) outputs so again, not the best.

I also have a spare PAC RP4-GM11 from my defunct TB.

 

[Matt]

I used this one: https://www.amazon.com/gp/product/B01MG2F61T/?tag=gmtnation-20 and it's working like a charm.

But, I really should have gotten a GMOS-04 to retain the fader controls.

 

[Reprise]

Another vote for the GMOS-04 - I've had mine for 2+ years, and not one issue.

Funny, that...seems the PAC guys have had issues with Metra, while the Metra guys have had issues with PAC. And no one likes / uses Scosche (except for front speaker adapters for the Bose-equipped units, perhaps)

(on edit - I have practically the same HU as @Matt - AVH-X3800BHS - and I'll attest to how easily it installed, and how good it sounds (I don't use the DVD capabilities - yet))

 

[Sparky]

Metra sucks, get PAC!
PAC sucks, use Metra!
Whatever you do, do not use Scosche!

 

[Reprise]

Metra sucks, get PAC!
PAC sucks, use Metra!
Whatever you do, do not use Scosche!

That reminds me - my current dash kit that I have for the Pioneer is a Scosche - and it's definitely inferior to the old one I had w/ my single DIN unit. That one...was a Metra

You'd think there shouldn't be much difference in a few pieces of stamped plastic - but there was

(full disclosure - I do not work for or have affiliation w/ Metra...I know I'm always giving off positive vibes about them)

 

[SEMIJim]

Metra sucks, get PAC!
PAC sucks, use Metra!
Whatever you do, do not use Scosche!

But what about Axxess?!?!

And how in the Wide, Wide World of Sports is one to figure out whether any of these will support the full set of features my current Bose radio does--including the... fader controls?!?! Really? Are we talking about the front/read fader? "Front speaker adaptors for Bose-equipped units?" Say what? Post-amp vs. preamp outputs? I've never even seen that mentioned, save here.

One car audio place I had give me a quote, when I started this little adventure, talked about how he knew how to get the Bose woofers working right with an after-market radio. I thought at the time "What's that mean?"

ETA: Axxess is Metra by another name? *sigh*...

 

[Matt]

OK, the GMOS-04 will retain everything including the fader. That's the one you want. The one I got (stupidly) does everything BUT retain the fader. Yes it is front to rear, that's what a fader does.

If you're just replacing the speakers and using the original wires, Bose uses a different connection, so the adapters allow for plug and play, rather than cut and hack.

 

[Mooseman]

But, but, on Bose systems, there is no fader!