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OK, so I tried another couple things.

1. I turned the head unit power off and turned the gain all the way down. When the car was running, I could feel the sub moving a little bit. When I removed the RCA's, it stopped. The aftermarket amp has power(remote signal) when the car is on. Must be the way the factory wiring is done.
2. With the HU still off and gain all they way down, I switched it from low pass to full range on the amp. The sub started making a higher pitch "squeal". Not sure how to explain it, but there's definitely some bad signal(interference) coming from the factory preamp.

Tomorrow I'm going to try to hook up a standard auto speaker and see what it does.

If it acts the same, I'm going to hook the factory amp back up and see if the issue goes away. I'm thinking the bose preamp is what is causing the factory amp to cut out. I sure hope that's not the case since that stupid thing is ~500 bucks and can't run the factory HU without it.....and I don't feel like doing a full aftermarket system(neither does my wife).
 

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All you'd need to do to replace it would be to wire in a new 4 channel amp (like ~$200) and it would replace the stock amp under the seat.

The stock Bose amp under the seat produces speaker level outputs for all of the speakers except the subwoofer. The subwoofer is the only driver in the system with an separate amp and the amp is physically attached to the driver. The stock Bose door amp also produces the line level output for the Bose subwoofer amp. I believe the Bose sub amp puts out ~100 watts @ 2 ohms.

The easiest way to test the sub signal you have now would be to attach an RCA to the end of it and run the signal to another audio system, like a home theater sub or something to see what happens.
 
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All you'd need to do to replace it would be to wire in a new 4 channel amp (like ~$200) and it would replace the stock amp under the seat.

The stock Bose amp under the seat produces speaker level outputs for all of the speakers except the subwoofer. The subwoofer is the only driver in the system with an separate amp and the amp is physically attached to the driver. The stock Bose door amp also produces the line level output for the Bose subwoofer amp. I believe the Bose sub amp puts out ~100 watts @ 2 ohms.

The easiest way to test the sub signal you have now would be to attach an RCA to the end of it and run the signal to another audio system, like a home theater sub or something to see what happens.
The amp I have is a 4 channel amp, so I may just use that one. We'll see.

Would that be 100W peak? I would thinks so since the full system is 200W according to the brochure(peak power for marketing sake?).

I'll have to try hooking it up to my garage stereo when I get home and see what it does.

EDIT: I was doing some more reading and I found some contradicting information. Is the brown wire the positive or is it the black/red stripe? I currently have black/red stripe as positive for the signal. I have a 07 Speed6, which I don't know if that's different than the regular 6.
 

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The brown is positive and black w/ red stripe is negative, the the larger blue with red stripe (power for Bose sub) can be tapped for remote. It should be the same for 03-08 regardless if it's a speed6.

Yes the 100w is probably peak at 2 ohms then the 4x 25w @ 2 ohms for the door speakers would make up the rest.
 

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The brown is positive and black w/ red stripe is negative, the the larger blue with red stripe (power for Bose sub) can be tapped for remote. It should be the same for 03-08 regardless if it's a speed6.

Yes the 100w is probably peak at 2 ohms then the 4x 25w @ 2 ohms for the door speakers would make up the rest.
This is likely the problem. Like I stated, I have black/red strip positive(going to center RCA pin) and brown as negative. I sure hope it's that easy.
I followed the instructions below, which states black/red strip as positive(signal) wire.
How-To: Wire a Sub to stock MAZDASPEED6


I have the blue as my remote, so that's good.
 

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I dunno, never seen that one before. He seems to overly complicate simple things. He doesn't seem to know what he's talking about when it comes to audio either from reading later posts.

Brown is positive, Black w/ red stripe is negative.
 

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So I did some more fiddling around last night.

I switched the black/red with the brown(so now the Blk/Red is on the outside and Brown is on the center) and get little to no sound from the amp. When I put black/red to the center of the RCA and brown to the outside I get sound(my original setup).

I hooked that directly up to my garage stereo and get a good sound, no distortion or humming.

I tried another auto speaker I had laying around and get the bad sound from the amp. The speaker is in a homemade bookshelf box.

I hooked up the factory amp again and get good sound from the sub.

I’m leaning towards the aftermarket amp as the culprit(or how it’s connected to they system). My brother said it was fine the last time he used it(but it’s been a while). I don’t think the issue is the power or ground since if I unhook the RCA’s, the noise goes away. I have 8 gauge power from the battery to the amp, 8 gauge ground that is ~1 foot from the amp(and seems to be a good ground according to my DMM). It must be some sort of feedback between the signal wires and amp.

What if I powered the amp with the same wires that power the factory sub for testing purposes? Think that’s worth a shot?

I was thinking last night that I should try another channel on the amp. Maybe the one output I’m using is bad but then again, that doesn’t make sense since the Ipod worked great.

This is frustrating since all I want is a little bass back(and not have it shut off half way home from work).
 

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You're using a 4 channel amp correct? Only using one of the channels or bridging a pair?

I would:

1. Try a different RCA
2. Try a different channel(s)
3. Swap the amp with another one, either one you have or if you don't have one you can just pick up one from Best buy and return it after you tested. It should be an easy swap.
 

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I’m running a 4 channel amp and running just 1 channel(not bridged) due to the Bose sub being ~2ohm impedence.

I’ll have to see about the RCA. I may do some rewiring so I can connect and disconnect different RCA’s. I currently have it all hardwired.

I’ll try a different channel as you suggest.

I may just do that with BB. Not usually a fan of that, but may be the best way to determine if it is the amp. I don’t have an extra laying around.
 

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Fixed(or bandaided). Put a ground loop isolator in and no more issues. My brother(who gave me the amp) brought over a ground loop isolator that he had laying around. We hooked it up and it works perfect. From what I’ve read though, GLI’s are more of a bandaid for bad grounding. I’m thinking it’s the head unit that has the grounding issues, but I’m happy so far. I am now able to set the bass to 0 and still have bass and it seems like the sub can hit lower notes, which I think is due to the “real” amp not having some goofy crossover’s built in like the factory amp.

EDIT: And by the way, I have the black/red stripe as my positive.
 

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Rattles!!

hi KoukiS14 and everyone else

hope am not asking a question already answered in this post.

i have a standard TS Saloon and yesterday i fitted a 10" sub in the same place you have put your yours all works well and rather improves on the stock stereo. Except the whole rear deck and the most of the boot rattles like mad and ruins the sound quality.

i was just wondering how you got round the rattles in the end?

cheers
joss
 

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Ok I'm going to put a disclaimer on this question because I know its stupid but I've never really done any wiring and I really want to attempt this myself.

So, I know I'm going to need a Y-Splitter for the RCA cables to my amp, I know that. I know that in the factory subwoofer connection, brown is positive and black with the red stripe is the negative. My really stupid question is how to I connect the Y splitter to the wires from the factory connection? Any response would be greatly appreciated!!
 

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Ok I'm going to put a disclaimer on this question because I know its stupid but I've never really done any wiring and I really want to attempt this myself.

So, I know I'm going to need a Y-Splitter for the RCA cables to my amp, I know that. I know that in the factory subwoofer connection, brown is positive and black with the red stripe is the negative. My really stupid question is how to I connect the Y splitter to the wires from the factory connection? Any response would be greatly appreciated!!
Not a stupid question... You need to make an RCA from those two wires. You can either cut them and solder them or crimp them. The brown goes to the center stud and the black/red goes to the shield.

You can get a DIY RCA from radio shack.
 

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Not a stupid question... You need to make an RCA from those two wires. You can either cut them and solder them or crimp them. The brown goes to the center stud and the black/red goes to the shield.

You can get a DIY RCA from radio shack.
Hey thanks for the quick response! That sounds easy enough. I've got all my wiring in the trunk from a previous system with the line-out converter that I'm going to take out and try this sleek set up.

Has anyone tried using a Kicker sub? Trying this one out.

Kicker 10C84 (10C8-4) 8" Single 4 ohm Car Subwoofer
 

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I initially went with the e3.8 but then change to the JBL GTO804 also and it's much better. I am in the process of testing it before I put everything back..found out that the seat belt bracket also rattle, you might want to take at that also...
Any other feedback about the JBL? I have a friend who wants to downsize rom a 12" Kicker L5 to an 8 inch woofer in the stock location. If you made it work for you, what do you recommend to insulate to eliminate more rattling?
 

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Any other feedback about the JBL? I have a friend who wants to downsize rom a 12" Kicker L5 to an 8 inch woofer in the stock location. If you made it work for you, what do you recommend to insulate to eliminate more rattling?
Insulate the entire deck top and bottom. Full in the open areas with fillafoam (small space version). My rattling was terrible until I did this!


Sent from AutoGuide.com App
 

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Insulate the entire deck top and bottom. Full in the open areas with fillafoam (small space version). My rattling was terrible until I did this!

I will let him know to try this out. I'm not sure if he ordered the speaker yet, but I know he was doing his homework on it and wanted to pick one up.
 

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So WHY does a new speaker rattle so badly, is it because ANY speaker besides OEM would rattle because of physical design, or is it just the volume you are now able to achieve exceeds stock baffling/dampening? I'd prefer not to insulate everything, if i can cut a felt or foam gasket and make it work i'd prefer that as I am looking for small occasional bursts of loudness, but if it is gonna rattle at vol 8-12 with bass at 6 (also have the home made EQ mod) then i might just skip it and sell my speaker...
 

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Sorry for the late response. I accidentally sent the notification to the weekly summary. Anyway, I have two answers to your question, but more importantly, why wouldn’t you want to sound deaden more? It seems pointless to me to invest in a sound system that is going to be plagued by rattles and road noise. I have a thread on 6Crew: http://www.6crew.com/forum/showthread.php?22617-Operation-Lexus-Quiet&highlight=lexus+quiet, which goes into using it.
On to your answers. There are two reasons why rattling occurs.

1. The back deck has areas in it that have two panels that are really close together, when you add the weight of a good sub (the factory BOSE sub is plastic and weighs nothing), these panels get very close together, enough so that when the base hits, they actually touch and buzz.

2. Output on the new sub is so much higher than the BOSE sub, plus the BOSE sub supports more midrange than true low end frequencies. These low-end frequencies cause all those little clips in the back deck to vibrate and rattle around crazy. You don’t really notice it at really high volumes, but lower volume will drive you nuts.

When I first swapped mine out, I did “spot” insulation, and ended up ripping everything apart again and re-doing it, fully.
 
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