D-Pillar speaker revisit - purpose and connections

[Meccanoble]

The speakers in the far back of the truck are the ones I'm referring to. Their position seems to be more of a "filler" position rather than a dedicated high or low like a tweeter or subwoofer. My audio expert friend confirmed they were a filler and not associated or connected with the rear door speakers, well maybe for power/signal but not a partnership like your standard components. Trying to replace speakers on stock amp in a way as if they were components would supposedly create sound problems. Not to say this feedback is true but it makes sense. The size of the speaker (3.5") gives it the ability to handle a wider spectrum of frequencies than just a tweeter or just a mid driver and its positioning, confirms it further, being in the far rear. Its almost like a center speaker. There is no dedication to highs or lows, just kind of fills the void.

It basically seemed worthless to upgrade this speaker under the stock amp setup unless you were going to change the amp it connects to which should then change its role or frequency range.

Anyone that swapped this speaker out on a stock setup hear this feedback? I assume if you tried to swap it out with a componenent set without using a crossover, its ability to play sounds as compared to tweeters elsewhere in the car would sound limited.

Instead, the rear door has a component set coming from just the rear door wiring alone. A crossover was added to the wiring to control frequencies that go to tweeter. Since speakers are now sharing the same power that came from amp, the combination wont get that loud but its just rear fill and plan to add amp later to pump up the power a little. But based off feedback I received, unless going aftermarket with amp, it doesnt seem to be ideal to consider that d-pillar speaker a matched componenet set with the rear door, which is what I was hoping it would be atleast (assuming people here already knew this).

 

[kbuskill]

Just out of curiosity.... what Ohm speakers did you replace your rear door speakers with???

The factory rear door speakers on the Bose system are 3.6 Ohm. I replaced mine with 3 Ohm Infinitys.

 

[Meccanoble]

I had some 4 ohm Helix Components I took out of a previous car. Honestly, they sound dissappointing because not only are they a higher ohm than the originals, but 4 speakers are getting power from wires that were powering 2. Its good enough for rear fill but I'm a cranker. Plus, my expectations were high, forgetting the amount of power they will have to share. Plus they are rated to take 70-125 watts and probably getting 20 rms max from HU. Thats like 10 to each speaker? Aftermarket radios only push low 20's at best. I had a busted yet working bose speaker on one side so it still sounds better than before but after hearing what my front end is doing with an aftermarket amp, its disappointing but understandable what the rear is doing.

Anyone that feels rear fill is not necessary or truly believes in what rear fill is 'supposed to be' will be content as it definitely serves its purpose but I'm a cranker. I definitely would waste money on components in the rear unless I was planning to get amp for them. Coaxials would definitely be enough.

 

[kbuskill]

I had some 4 ohm Helix Components I took out of a previous car. Honestly, they sound dissappointing because not only are they a higher ohm than the originals, but 4 speakers are getting power from wires that were powering 2. Its good enough for rear fill but I'm a cranker. Plus, my expectations were high, forgetting the amount of power they will have to share. Plus they are rated to take 70-125 watts and probably getting 20 rms max from HU. Thats like 10 to each speaker? Aftermarket radios only push low 20's at best. I had a busted yet working bose speaker on one side so it still sounds better than before but after hearing what my front end is doing with an aftermarket amp, its disappointing but understandable what the rear is doing.

Anyone that feels rear fill is not necessary or truly believes in what rear fill is 'supposed to be' will be content as it definitely serves its purpose but I'm a cranker. I definitely would waste money on components in the rear unless I was planning to get amp for them. Coaxials would definitely be enough.

The 4 ohm speakers are causing you to loose some volume.

Your setup with 4 ohm doors and stock 12.5 Ohm D-pillars = 3.03 ohms

Factory door speakers and D-pillars = 2.79 ohms

My 3 ohm doors with stock D-pillars = 2.41 ohms

So mine are slightly louder than stock.

I think your biggest problem is probably the wattage rating and possibly the sensitivity.

My Infinity PR6500CS 's are 5-80W RMS and sensitivity 93db.

 

[Meccanoble]

Agreed. Whether its a coaxial set or component set, the ohms & sensitivity will play the biggest role with how loud it gets.

Regarding the D pillars, anyone replace stock speakers in D Pillar and notice its not playing right? I wouldnt mind throwing better tweets in there if I knew it would play the frequency range I wanted

 

[Meccanoble]

Question, if the D-Pillar speakers were disconnected, that would put more power to the rear doors right? I believe they are somehow connected together (rear doors and the d-pillar) so maybe cutting certain wires on amp will stop them from working and put more power to rear doors? Or would I have to disconnect from the speaker side since they run as 1 unit into the amp?

Just looking for cheap ways to improve sound

 

[kbuskill]

Question, if the D-Pillar speakers were disconnected, that would put more power to the rear doors right? I believe they are somehow connected together (rear doors and the d-pillar) so maybe cutting certain wires on amp will stop them from working and put more power to rear doors? Or would I have to disconnect from the speaker side since they run as 1 unit into the amp?

Just looking for cheap ways to improve sound

Kinda sorta maybe not really.... lol

I don't remember what speakers you are running so I will just use the factory specs as an example.

Factory rear door speaker = 3.6 ohms
Factory D-pillar speaker = 12.5 ohms

For a total load seen by the Amplifier of about 2.8 ohms

If the speakers are wired in parallel, which they are, then the lower impedance speakers will draw more power than the higher impedance speakers.

So your door speaker is already getting more power than the D-pillar... it's not like a 50-50 split.

So by disconnecting the D-pillar speaker you will send all 100% of the power to the door speaker BUT you would also increase the ohms seen by the amp from 2.8 ohms to 3.6 ohms which will mean less power from the amp.

What I'm saying is it MAY be a wash.

The easiest thing to do is unplug the D-pillar speakers while playing a song and see if it makes any noticeable difference.

 

[Meccanoble]

Speakers in rear door are 4 ohms. From your feedback, there wont be a big improvement and I never opened up those D-Pillars so I'll wait until I'm ready to change an amp or something before I open anything up. Thanks for the feedback. I always thought it was a 50/50 split....

 

[Doubeleive]

when I had my nbs I changed the rear pillar speakers to 3" I don't recall the brand name, they where European and had big magnets I had to cut away some of the back of the pillar cover plastic with a razor knife to make it work but when the covers were put back on you couldn't see the difference. I then ran the pillar speakers on the amp from the head unit (pioneer) and the door speakers were on a amp I put under the seat and the subwoofer had it's own amp. overall all it just added more sound if you were in the back seat you could hear them rather than the door speakers. I had also added the bose front pillar tweeters in addition to the front door tweeters.

 

[kbuskill]

Speakers in rear door are 4 ohms. From your feedback, there wont be a big improvement and I never opened up those D-Pillars so I'll wait until I'm ready to change an amp or something before I open anything up. Thanks for the feedback. I always thought it was a 50/50 split....

If they were both the same ohms then it would be a 50/50 split. If you changed your door speakers from those 4 ohm to 3 ohm you would get a "little" more power to them and therefore a "little" more sound.

Right now you are running approximately 75% of the power to the 4 ohm door speaker and 25% of the power to the 12.5 ohm D-pillar speaker.

Swapping to a 3 ohm door speaker would only result in an 80/20 split, so not a drastic difference.

Unplugging the D-pillar speaker would result in 100% power to the door speaker BUT it would be at 4 ohms instead of the 3 ohms your currently running.

From the results above when changing from the 4 ohm to the 3 ohm we see that it is only a 5% difference in power so in theory you would still net about a 20% increase in power so it might be worth it.

Pulling the D-pillars to unplug the speakers wouldn't take very long and I would be truly interested in the results.

If you don't do it then I may be forced to... lol