2010 Tahoe LTZ Front Speaker Upgrade

[lemansguy]

Ive had the tahoe for a couple years as the wifes DD, but we just upgraded her to a new vehicle and the tahoe is now mine. Ive started upgrades and one thing i want to do is the stereo. I understand how to add an amp and sub to replace the stock sub, and already have items waiting for instal, but im trying to understand the best way to upgrade the front sound stage. Ive been doing a lot of reading and searching on keeping the stock bose amp, and just installing a decent component speaker to replace the the stock door and A-pillar tweeter. From what ive been reading the door speakers are about 2ohm, and the tweeters are an unknown ohm. the speakers are wired in parallel so it is currently unknown what resistance the amp is seeing.

My question is, should i buy a set of components at 4ohm or 2ohm to replace front doors and tweeters? Im not looking to add an additional amp for the door speakers, i just want something that i can have all windows down at 80mph and have the stereo loud without distortion. Right now the front tweeters start to wash out at high volumes. i just want to find the best speaker pairing to the stock bose amp. thanks for your help

 

[Meccanoble]

If no additional upgrades with amp or head unit, I would go 2 ohms in front and 4 ohms in the back for maximum sound.

 

[swathdiver]

My question is, should i buy a set of components at 4ohm or 2ohm to replace front doors and tweeters?

@kbuskill @Rocket Man

I've summoned help from the experts! One thing I learned about the dumb or non-Lux amp is that as the volume is turned up, the bass is reduced to protect the speakers.

 

[lemansguy]

@kbuskill @Rocket Man

I've summoned help from the experts! One thing I learned about the dumb or non-Lux amp is that as the volume is turned up, the bass is reduced to protect the speakers.

thanks! ive read kbuskill's threads on his speaker upgrade, but it appears he didnt upgrade the tweeters. i actually used his research to come to the front speaker resistance information. Ill have to check out Rocket man's posts now too.

i was really hoping to keep the stock head unit to avoid buying interfaces to keep factory controls and such.

 

[lemansguy]

If no additional upgrades with amp or head unit, I would go 2 ohms in front and 4 ohms in the back for maximum sound.

what affect will that have on the amp if it is set for a 4 ohm total load for the front stage? i know i could just throw a pair of speakers in there, i just like to know exactly whats going on before i do anything.

 

[Rocket Man]

what affect will that have on the amp if it is set for a 4 ohm total load for the front stage? i know i could just throw a pair of speakers in there, i just like to know exactly whats going on before i do anything.

For a stock amp, you want to match replacement speaker impedance with what's in there from the factory or the amp won't function correct. It's designed for a specific load, unlike aftermarket amps. On mine, the front and rear door speakers were 2 ohm from the factory and I replaced them with 2 ohm JBL coaxials (gto-628) which have a separate tweeter mounted in the speaker. These, combined with the a-pillar tweeters, seemed to sound pretty bright. They work real well on the LUX amp. I have a 10" JL sub in an MTX Thunderform enclosure running off a separate amp for bass so if the stock amp is turning down the bass as the volume goes up, I don't notice it since it doesn't affect the sub. The Sony DD HU has great adjustability on all the channels and sub output so everything can be dialed in. I call it a hybrid system since it incorporates the LUX amp with aftermarket components (speakers, HU, sub and it's amp). That way I didn't have to tear out all the wiring and the stock amp and start from scratch. I can roll at 80 with the windows down and it still sounds great. My experience is only with the LUX amp though, I don't know how well the standard Bose amp sounds.

 

[lemansguy]

For a stock amp, you want to match replacement speaker impedance with what's in there from the factory or the amp won't function correct. It's designed for a specific load, unlike aftermarket amps. On mine, the front and rear door speakers were 2 ohm from the factory and I replaced them with 2 ohm JBL coaxials (gto-628) which have a separate tweeter mounted in the speaker. These, combined with the a-pillar tweeters, seemed to sound pretty bright. They work real well on the LUX amp. I have a 10" JL sub in an MTX Thunderform enclosure running off a separate amp for bass so if the stock amp is turning down the bass as the volume goes up, I don't notice it since it doesn't affect the sub. The Sony DD HU has great adjustability on all the channels and sub output so everything can be dialed in. I call it a hybrid system since it incorporates the LUX amp with aftermarket components (speakers, HU, sub and it's amp). That way I didn't have to tear out all the wiring and the stock amp and start from scratch. I can roll at 80 with the windows down and it still sounds great. My experience is only with the LUX amp though, I don't know how well the standard Bose amp sounds.

I fully agree and understand what you are saying, but since the front door and tweeter speaker are run in parallel per kbuskill posts, how do we know what the amp wants to see? thats where my question comes from. the speakers in the doors are 2ohm, but the unknown tweeters would change what teh amp is seeing. so is it better to buy 2 ohm components to replace it all with? i really like having the tweeters in the A pillar to keep that front sound stage. i guess worst case i just buy 2 ohm components, and take my chances on how the aftermarket tweeters sound vs the stock ones. either way the door speaker will be an upgrade.

all of my online research shows people either replacing everything, or just replacing doors. i havent found anyone with a bose amp who replaced their tweeters and door speakers together, and ran them off the bose amp.

sorry if this is a bit of a ramble, i tend to research thing for a couple weeks before i post on forums. just not as much info on these trucks vs others out there. probably due to so many variables and options offered by the dealer.

 

[Rocket Man]

I fully agree and understand what you are saying, but since the front door and tweeter speaker are run in parallel per kbuskill posts, how do we know what the amp wants to see? thats where my question comes from. the speakers in the doors are 2ohm, but the unknown tweeters would change what teh amp is seeing. so is it better to buy 2 ohm components to replace it all with? i really like having the tweeters in the A pillar to keep that front sound stage. i guess worst case i just buy 2 ohm components, and take my chances on how the aftermarket tweeters sound vs the stock ones. either way the door speaker will be an upgrade.

all of my online research shows people either replacing everything, or just replacing doors. i havent found anyone with a bose amp who replaced their tweeters and door speakers together, and ran them off the bose amp.

sorry if this is a bit of a ramble, i tend to research thing for a couple weeks before i post on forums. just not as much info on these trucks vs others out there. probably due to so many variables and options offered by the dealer.

I left the stock tweeters in the a-pillar and the wiring the same. The new speakers with their separate tweeters were 2 ohms the way they're wired from JBL so the circuit stays the same. If you're replacing a door speaker with components, you'd need to wire the mid and tweeter so the total is 2 ohms if that's what was there before. If you want to replace the a-pillar tweeters, just pull one and measure it so you can get a replacement that's the same impedance. The only other way, if you want to eliminate the a-pillars or change the impedance in any certain location, would be to find the outputs from the amp to that front circuit, disconnect it and measure it. Then you'd have to experiment with speakers until you got that same impedance. I just decided to keep each location the same as what I pulled out in order to keep it simple. Hope that helps.

 

[lemansguy]

I left the stock tweeters in the a-pillar and the wiring the same. The new speakers with their separate tweeters were 2 ohms the way they're wired from JBL so the circuit stays the same. If you're replacing a door speaker with components, you'd need to wire the mid and tweeter so the total is 2 ohms if that's what was there before. If you want to replace the a-pillar tweeters, just pull one and measure it so you can get a replacement that's the same impedance. The only other way, if you want to eliminate the a-pillars or change the impedance in any certain location, would be to find the outputs from the amp to that front circuit, disconnect it and measure it. Then you'd have to experiment with speakers until you got that same impedance. I just decided to keep each location the same as what I pulled out in order to keep it simple. Hope that helps.

That does help. Pulling the tweeter may just be what I have to do. I appreciate it running it through with me.

 

[kbuskill]

@lemansguy @Rocket Man

The tweeter will have an affect on what the amp "sees"...

For example... let's assume that the rear channels and front channels on the amp expect to "see" the same load (ohms).

The rear door speakers on my NON-LUX amp are as follows from the factory:
Rear doors = 3.6 ohm
Rear D-pillar speakers = 12.5 ohm

Ran parallel they combine to equal...
3.6 X 12.5 = 45
3.6 + 12.5 = 16.1

45 ÷ 16.1 = 2.795 or 2.8 ohms or 3 ohms if you will.

So one would assume that the front channels of the amp would also like to see around 3 ohms but it is impossible to find an aftermarket tweeter with the proper ohm rating to achieve the 2.8 or 3 ohms that, when ran parallel with the 1.9 ohm door speaker, we "assume" the amp would be looking for.

I will save all the steps and just give you the results from running the math...

1.9 ohm front door speaker ran parallel with a...

1 ohm tweet = .655 ohm at amp
2 ohm tweet = .974 ohm
3 ohm tweet = 1.16 ohm
4 ohm tweet = 1.28 ohm
8 ohm tweet = 1.535 ohm
12 ohm tweet = 1.64 ohm
24 ohm tweet = 1.76 ohm
48 ohm tweet = 1.827 ohm
96 ohm tweet = 1.863 ohm
192 ohm tweet = 1.881 ohm
384 ohm tweet = 1.890 ohm
768 ohm tweet = 1.8953 ohm
1536 ohm tweet = 1.89765 ohm

You get the idea... not gonna happen.
So the amp must look for a different ohm rating up front.

Unfortunately the tweets are not marked like the rest of the speakers.

My 3 ohm tweets out of my component set, that I installed the mid bass drivers in the rear door, would cause the amp to see 1.16 ohms if I installed them in the factory A-pillar location... I think... I'm not 100% sure how they measure components when separated and not ran through the supplied crossover.

I also installed coaxials in the front doors and the factory A-pillar speakers sound just fine to me... my Kappas have an attenuation switch on the center mounted tweeter... it cuts 3db out of the tweets when pushed in... I pushed it in to get rid of some of the "brightness"... between them and the factory tweets there is plenty of highs.

Hope this all makes sense... and helps.

Tagged Rocket Man to check my numbers and keep me straight... lol

 

[Rocket Man]

Those numbers are right according to my parallel resistors calculator that I used. Yes I cheat. But you can never assume what the amp is designed for. Most the tweets I've seen are 4 or 8 ohm btw.

 

[kbuskill]

Those numbers are right according to my parallel resistors calculator that I used. Yes I cheat. But you can never assume what the amp is designed for. Most the tweets I've seen are 4 or 8 ohm btw.

What are your thoughts on my component speakers, which are rated at 3 ohms, when separated and without the crossover?

My understanding is that the mid bass and the tweet are both 3 ohm which, when ran parallel, would actually be 1.5 ohm to the amp BUT since the crossover doesn't allow the speakers to play the same frequencies it remains a 3 ohm load...

Of course my understanding and way of thinking may be way off base.

If this is true then the capacitor on the factory Bose A-pillar tweeter may/should have a similar affect.

 

[Rocket Man]

What are your thoughts on my component speakers, which are rated at 3 ohms, when separated and without the crossover?

My understanding is that the mid bass and the tweet are both 3 ohm which, when ran parallel, would actually be 1.5 ohm to the amp BUT since the crossover doesn't allow the speakers to play the same frequencies it remains a 3 ohm load...

Of course my understanding and way of thinking may be way off base.

If this is true then the capacitor on the factory Bose A-pillar tweeter may/should have a similar affect.

It's been a long time since I was an electronic tech and honestly I do not remember what effect, if any, a capacitor has on the total resistance in a parallel circuit. I would be inclined to just wire them up and measure with a DVM if possible.

 

[lemansguy]

thanks guys for all the input and thought. im going to keep on digging and see what turns up. i may just go for it at some point and see what happens...

 

[lemansguy]

so ive been doing more digging and found this info on a diesel forum...

"basically, there are three different GMT-900 bose amplifiers.

1. "premium"/non-luxury Bose. 9 speakers (7 in trucks). Speaker in each door, subwoofer in center console, and a-pillar tweeters. SUV's get 2 additional speakers in the d-pillars.

2. Luxury Bose. 10 speakers; has an additional center-channel speaker in the upper dashboard. This amp has better sound than non-lux and more bass but does NOT have 5.1 discrete audio inputs for 'true' surround sound when watching dvd's. The center channel is "matrixed" (created out of thin air so to speak) within the amp's signal processing; it does not get an actual center-channel audio signal from the radio. Basically 2 channel sound, even when watching DVD's.

3. Luxury 5.1 Bose. 10 speakers, just like the lux, center channel speaker. This amp has the best sound, and has discrete 5.1 audio inputs. Meaning, the radio actually sends out 6 separate audio signals to the amplifier and the amp plays those discrete audio signals on their respective speaker. IE, if you are watching a DVD with this Bose amp, you get true surround sound; when the bad guy is shooting a gun behind you, you actually hear the gunshot coming from the rear speakers, etc...

In 2007-2008:
-you could only get amp (3) in the Escalade.
-you could only get amp (2) in the Denali.
-you could only get amp (1) in the silverado/sierra/tahoe/suburban

In 2009:
-you could get amp (3) in the escalade, denali, and Tahoe/Suburban (LTZ only), and only if you get the rear seat entertainment/DVD/nav unit.
-you could only get amp (2) in the denali's without rear seat entertainment/DVD
-you could only get amp (1) in the tahoe, silverado, sierra, yukon, suburban without DVD and without the LTZ package.

Even If you got a Tahoe LT (or any silverado/sierra) with DVD and everything though, you would still only get amp (1) because amp (3) is reserved for LTZ SUV's. LTZ pickup trucks do not get amp (3)

In 2010:
they basically got rid of the amp (2). Now you can only get amp (1) or amp (3).
-you can only get amp (3) in all escalades and all denali's (doesnt matter if it has rear seat DVD or not)
-you can only get amp (1) in all silverados/sierras, even if it has rear seat DVD.
-you can only get amp (1) in tahoe LT's, even if it has rear seat DVD.
-in order to get amp (3) in a tahoe or suburban, you must have LTZ and rear seat DVD"

So according to this guy i have the LUX amp, cuz i have a 2010, LTZ with rear dvd and center speaker.... so i guess i need to go back and reread posts that discuss the LUX amp outputs and power specs

 

[lemansguy]

It's been a long time since I was an electronic tech and honestly I do not remember what effect, if any, a capacitor has on the total resistance in a parallel circuit. I would be inclined to just wire them up and measure with a DVM if possible.

here is a video i found explaining the above.

if the tahoe is using a capacitor as a crossover then that should net the same results from what i understand. Bottom line the tweeter isnt being seen by the amp because of the lack of power the tweeter requires to run even at full capacity. So whatever your woofer is rated at will be what your amp sees.

 

[Rocket Man]

here is a video i found explaining the above.

if the tahoe is using a capacitor as a crossover then that should net the same results from what i understand. Bottom line the tweeter isnt being seen by the amp because of the lack of power the tweeter requires to run even at full capacity. So whatever your woofer is rated at will be what your amp sees.

Ah yes and now I remember that speakers act completely differently than a resistor in circuits and are rated in terms like "nominal impedance" and also why I'm no longer an electronic tech- just thinking about that shit drives me crazy. And these are the simplest circuits there are- you should do the math on complex circuits with many more types of components wired in all types of configurations. I used to get headaches trying to troubleshoot circuits using formulas and such and found it easier and more effective to "troubleshoot light" as I used to call it. It resulted in me replacing more components than needed but I could get the stuff fixed faster than other guys and the components were cheap, it's the labor that cost the money. Anyway enough about my past, good video. Now you just need to know if there's a capacitor on the tweeter which I would assume there is. The guy only shows the charts though and doesn't discuss what a DVM will see so there's also that to consider, although I believe you'll see the same as what he showed until you push on a cone which makes the impedance change. The JBL's I installed showed 2 ohms with the tweeters installed on them, wired parallel to the mids with capacitors for crossovers. It's easier if a person is designing a circuit from scratch like he was, but what if you're adding to an existing circuit like in the vehicle where there's already a circuit designed? If you have the schematic it would help of course. This is also why I tried to keep each component of the circuit the same as what was designed originally.

 

[lemansguy]

Digging this up from the dead a bit for an update. Finally decided on a speaker and purchased these today.
https://www.amazon.com/gp/product/B00ANI3LAK/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

great reviews, decent price and 3 ohm load. not sure when i will get around to installing them yet because i want to sound deaden the doors at the same time. ill try and get some pics when i finally do though.

 

[Rocket Man]

Digging this up from the dead a bit for an update. Finally decided on a speaker and purchased these today.
https://www.amazon.com/gp/product/B00ANI3LAK/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

great reviews, decent price and 3 ohm load. not sure when i will get around to installing them yet because i want to sound deaden the doors at the same time. ill try and get some pics when i finally do though.

I have the JBL 6 1/2” 3-ways in all 4 doors and they sound great.