D-Pillar speaker revisit - purpose and connections

[swathdiver]

I assume the splice is somewhere in the door harness and not at the amp.

Probably somewhere around there. The wiring diagram I consulted doesn't say where.

 

[Meccanoble]

Copy. So if I was to get an amp to connect to the wiring at the bose amp, what ohms should those d-pillar speakers be to run a 4 ohm load to the amp, with the fact that i'm already running 4 ohm speakers at the doors. I understand if I dont connect any d-pillar speakers, it will be a 4 ohm load going to amp.

On another note, I also think its safe to assume that the d-pillar speakers are considered "fillers" not because of the way the bose amp has them configured (since they share the channel) but rather because of their small size, they can only play a limited frequency? I guess there could be a capacitor connected somewhere too but I didnt see anything out of the norm on the speaker side, maybe the difference is at the door. Using stock wiring, I want to make sure we ONLY limited on frequency by speaker's ability perform and nothing else, if we changed out speakers and amp.

 

[kbuskill]

Copy. So if I was to get an amp to connect to the wiring at the bose amp, what ohms should those d-pillar speakers be to run a 4 ohm load to the amp, with the fact that i'm already running 4 ohm speakers at the doors. I understand if I dont connect any d-pillar speakers, it will be a 4 ohm load going to amp.

On another note, I also think its safe to assume that the d-pillar speakers are considered "fillers" not because of the way the bose amp has them configured (since they share the channel) but rather because of their small size, they can only play a limited frequency? I guess there could be a capacitor connected somewhere too but I didnt see anything out of the norm on the speaker side, maybe the difference is at the door. Using stock wiring, I want to make sure we ONLY limited on frequency by speaker's ability perform and nothing else, if we changed out speakers and amp.

You would need to run a 120 ohm D-pillar speaker with the 4 ohm door speaker to get 3.9 ohms at the amp.... lol

Conversely an 8 ohm speaker in both locations would give you 4 ohms at the amp.

OR you could get an amp that is stable at 2 ohms and run two 4 ohm speakers.

 

[Meccanoble]

LMAO @ 120 ohm

The 3rd option seems best since I still need an amp. I never seen 8 ohm coaxials nor components or never bothered to look. Appreciate the feedback.

 

[Meccanoble]

Just wanted to share that I was trying to set gains on my amp and when I used HU to turn my rear speakers off (pioneer 4200 nex has this option), the volume goes lower but does not turn off all the way. Any reason why? I'm guessing the d-pillar speakers are not considered rear in the wiring setup? so sound still comes across? How can wiring alone determine which speakers are rear and which ones are not? This makes me think the d-pillar speakers have a different input into the bose amp, right? If they were all wired together as 'rear speakers', turning rear speakers off should cut them all off, not just 1 set. This is beyond a cross over that can just turn off certain frequencies. HOw would this be possible if they come into amp as the same signal????

 

[Meccanoble]

Regarding all speakers in general, I would play 40 hz test tones and hear sound from front components which are set at 80 hz HPF. I understand there is a roll off/slope but didnt think I would hear. Same on the opposite side where 100 hz plays on sub taht is set for 80 hz LPF. Is this all due to slope? I have slope at highest setting (I think 18 or 24). I literally have to turn sub off or unplug front rca's to stop them from making sound. Amp is fully open but set the HU crossovers.

 

[iamdub]

Even at "only" an 18dB slope, a 40Mhz difference should be cut. Maybe raise the center frequency of the high-pass and adjust the slope to bring in the lower (lower as in mid, not sub) frequencies? Of course, you'd do the opposite on the sub crossover. Maybe the center frequencies of both are too close, regardless what they're labeled as on the HU.

 

[Meccanoble]

I'll try that. I was using a youtube test tone so not sure if the source playing makes a difference. I'll test highter frequencies to see what happens. I am happy so far with the current setup which actually has overlapping front/rear > 80, sub < 100
But was just surprised that speakers werent doing what I expected them to do.

But regarding this topic, what does that say about the rear, if turning rear off from HU doesnt truly turn rear off? I dont have dpillar speakers connected anymore so whatever would have come out of them is probably now coming out of rear doors but I thought everything rear would be turned off. All wiring I seen only discusses rear speakers, no additional wiring for d-pillar. Does this mean D-pillar has its own independent setup? I'm lost because this is not a frequency/slope issue. Rear either should be turned on or off, not halfway....

 

[Meccanoble]

You would need to run a 120 ohm D-pillar speaker with the 4 ohm door speaker to get 3.9 ohms at the amp.... lol

Conversely an 8 ohm speaker in both locations would give you 4 ohms at the amp.

OR you could get an amp that is stable at 2 ohms and run two 4 ohm speakers.

So I currently have my Helix components connected to PPI 900.4 2 channels @ 4 ohm. This is 4 ohm set but without crossover. I assume they still are 4 ohms even without the crossover connected? They just have a capacitor limiting what tweets get. I have some Infinity tweets I got for free that I will hook up in d-pillar. They show 150 watts max. I believe this will have them running in parallel @ 2 ohms which will be 225 watts per channel. Thats about 115 watts for each set. Should be interesting

 

[Meccanoble]

infinity 1031t, just realized they 3 ohms, not going to work

 

[Meccanoble]

Well that would give me a total impedence of 1.7 ohms. My amp is 2 ohm stable. Would that be close enough or anything under 2 is risky?

 

[Meccanoble]

Seems like a conversation with myself but after talking to my guru friend, the stock speakers at 12.5 ohms will give me a total of about 3 ohms? That should do the trick and bring out the stockers more with real power going to them. Will plug those back in and see how they shine

 

[GranPrix]

So I upgraded all 4 door speakers with some pioneers I've had laying around. (they are all 4 ohms) Seems my PPV didn't come with the d pillar speakers. I have a set of OEM d pillar speakers with the same color wires as the rear door speakers. Should I even bother adding them?

 

[iamdub]

So I upgraded all 4 door speakers with some pioneers I've had laying around. (they are all 4 ohms) Seems my PPV didn't come with the d pillar speakers. I have a set of OEM d pillar speakers with the same color wires as the rear door speakers. Should I even bother adding them?

I wouldn't bother. They're really more for rear passengers.

 

[Meccanoble]

If you are using stock amp, the d-pillar speakers will take power away from the door speakers. They share same wiring so it will hurt the other speakers. More speakers are better but the stock setup already bad at powering aftermarket speakers, I wouldnt add. In my case, not only was I using aftermarket amp but my rear was too loud for the car so sharing that power with other speakers helped since the tweets which are installed on the rear doors (right next to front passenger ears) stopped getting the same power.

 

[GranPrix]

Yea I never wired them, i'm only using the doors.

 

[Hoganator]

One of my D Pillar speakers is fried and buzzing. I just want to replace the pair (with upgraded units) in those locations, keeping the rest of the system stock. I'm all confused with the ohm thing being discussed and I've been on Crutchfield for their recommendations for replacements and its leaving me more confused.

Can anyone pinpoint me on what ohm speaker or suggest a specific brand/model that will work back there or should I just replace with an OEM Bose unit since its just used to 'fill?'

 

[kbuskill]

One of my D Pillar speakers is fried and buzzing. I just want to replace the pair (with upgraded units) in those locations, keeping the rest of the system stock. I'm all confused with the ohm thing being discussed and I've been on Crutchfield for their recommendations for replacements and its leaving me more confused.

Can anyone pinpoint me on what ohm speaker or suggest a specific brand/model that will work back there or should I just replace with an OEM Bose unit since its just used to 'fill?'

Do you have the "Luxury" Bose system or the standard "Premium" Bose system?

Actually I just noticed your signature and it says you have a 2016 Denali. Not sure if they changed anything on the K2XX platform.

 

[Hoganator]

Sorry, I haven't updated my profile. My project build is a 2007 Suburban Z71, but not sure on the Premium or Luxury though...would a Z71 package have one or the other usually?

I'm doing more reading and sounds like I need a 2 ohm speaker but I don't want to mess with the rest of the system at this point...just wanna get rid of the buzzing back there. I'd prefer to upgrade the speakers but not at the expense of messing something else up which I'm finding a lot with builds..lol

 

[kbuskill]

Sorry, I haven't updated my profile. My project build is a 2007 Suburban Z71, but not sure on the Premium or Luxury though...would a Z71 package have one or the other usually?

I'm doing more reading and sounds like I need a 2 ohm speaker but I don't want to mess with the rest of the system at this point...just wanna get rid of the buzzing back there. I'd prefer to upgrade the speakers but not at the expense of messing something else up which I'm finding a lot with builds..lol

Bose D-pillar (3.5") speakers are 12.5 ohm for the non-LUX system and 3.25 ohm for LUX Bose system.

If you have a speaker in the center of your dash then you have the Luxury Bose system.

If you DO NOT have a speaker in the center of your dash then you have the Premium Bose system.

With your truck being an '07 Suburban I would venture to say that you, more than likely, have the Premium Bose system, in which case you would need a 12.5 ohm speaker which is not common in the aftermarket.

Here is a link to one of my previous posts that you find interesting...

https://www.tahoeyukonforum.com/threads/bose-speakers.101909/page-5#post-1228439

Your best bet would probably be to replace it with a factory speaker.

Any more questions just ask.