bmak

iTrader: (4)

Well, I wouldn't say "never". But in the general sense, yes. A 10 gauge wire will only help this situation.

interog8

Just looking now for some advice on a good common ground point for my HU/Metra kit/PAC? Any thoughts on this area behind the glove box? Looks like unpainted metal attached to the chassis. Any opinions or suggestion would be appreciated

Tamas

iTrader: (1)

That looks fine to me, but it's pretty simple to verify with a multimeter.
It would surprise me if it didn't work.

interog8

So....I used the Metra kit setup and purchased the crutchfield rca to wire connectors shown in this post and no matter what I do I KEEP getting ground loops!!! Anyone else have this problem using wire to rca connectors? If so, would love to know how you fixed this.

bmak

iTrader: (4)

I'd love to help, but it's really hard to do that with only knowing the problem and that you've tried something. Can you let us know what you've tried specifically?

Munchy

iTrader: (2)

I had the same problem interog8. Used the RCAs and got buzzing all kinds. Tried a better ground and still.

Just yank them and stick to the original cables, only thing that's messed up is the volume levels. (i.e. volume 4-5 is normal and 10 is SUPER loud)

firebirdude

iTrader: (3)

That's exactly what the RCAs are an attempt to avoid. Using the headunit's built-in amp, to send to the Bose amp to be amplified yet again. Some headunit have a "sound level adjustment" setting (SLA). This changes the volume level for different audio sources. Maybe you don't want the radio the same volume when you eject a CD for example. Maybe you could try setting them all to a negative value? So it takes more volume **** to reach the same volume? Really a band-aid fix, but might help.

Munchy

iTrader: (2)

I'll check if my AVH-P3400BH has that feature.

interog8

Thanks all the for the replies!! I basically have done exactly what Munchy did - I used a cheap set of rca's initially, then bought expensive ones - I have reworked the grounding 3 times and nothing!! It is extremely frustrating. I might end up doing what Munchy suggests and just pull the rcas and go straight with the wires. I had read about the volume problems firebirdude mentions so I was really hoping to go rcas. Has anyone not had the buzzing with the rcas, or is this such a common problem that everyone is just doing the band-aid fix firebirdude speaks of by adjusting the hu settings? Thanks!!

firebirdude

iTrader: (3)

page 59

bmak

iTrader: (4)

interog8, at this point, I'd take it to a professional shop, explain exactly what's happening and what you've tried. I would expect that just helping to fix a problem like this would not be terribly expensive. I'd offer to help myself, but Alberta is not exactly close to Boston.

Munchy

iTrader: (2)

Mine was done by a professional installed, and still has buzzing. He even said there was probably gonna be buzzing BEFORE he put the RCAs in.

and thanks firebirddude!

firebirdude

iTrader: (3)

The RCA work around is something commonly done with ANY amplified factory system. I didn't think it up nor is it RX8 specific. I've used this method on more model cars than I can remember. Sometimes it works perfectly and other times you get noise.

But I'll tell you one thing.... a sure fire way to cure it.... install your own amp and speakers

interog8

Thanks again everyone!! And I appreciate the willingness to help bmak . I'll play around with the hu settings today to see if I can work around it. If not, you are totally right firebirdude, I'll just upgrade the amp and speakers at some point this summer. Thanks again bmak/Munchy/firebirdude, I really appreciate the help/feedback!!!

Munchy

iTrader: (2)

I finally finally got EVERYTHING working concerning the radio:

-Radio works
-All buttons on HVAC work
-All lights on HVAC work
-Radio isn't rattling anymore (actual metal casing of radio was rattling)
-I thought my Mode and SRC buttons were reversed, but I'm just an idiot
-Wrapped my dash kit in 3M DI-NOC to cover the shitty gloss paint job
-Not using RCA wires, so only thing not normal is the volume levels, but I can live with that (need to look into sound levels option)

Yay for me!

RX8Geek

Munchy - you might want to try "padding" the high level radio outputs. I have attached a drawing of a single channel pad, using 3 1/4W resistors. You can probably get them at Radio Shack. If not, DigiKey.com.

If you have the skills to solder and then insulate the connections, this method is virtually free, and it will reduce your volume level without introducing noise.

If the result is still too loud (probably won't be), you can decrease the value of the 18 ohm shunt resistor. Good luck.

ccrooks

I'm going through the same thing right now. I have the AVH-P3400BH just like Munchy, but haven't connected it fully yet. I was about to plug it in last night and remembered seeing something about the RCA-to-wire adapter, so I figured I'd hold off on putting it back in until I got a set of these... but if they don't work well, what's the point?

I'm also still hunting for a good grounding point behind where the old head unit was or under the dash anywhere... it looks like EVERYTHING down there is plastic/rubber!

By the way, where does the black wire in the old wiring harness attach to? Is this the ground point for the old head unit?

firebirdude

iTrader: (3)

The RCA hack method is a trick I've used on many factory amplified systems. I have had no problems in some cases and engine whine in other cases. Depends on the car. It appears as though the RX8 gives people trouble with the RCA hack, so I've started recommending the resistor padding method mentioned above. Takes a little more time, but using those high-level outputs should eliminate any induced noises.

Overall, I think Metra should have/should now make a work around for those with Bose. Include two sets of speaker wire connection on the Axxess box, one labeled Bose and one labeled non-Bose for example. The Bose connections just has a series of resistors soldered on the PCB inline. Problem solved and a lots less headaches for everyone, Metra included.

ccrooks

so with the resistor shunt method, you just need 3 resistors - 2 in series with the speaker wires, and 1 in parallel? Should be easy enough to solder up, i'd just be wary of the durability... but I might give this a shot

in my auto-pilot soldering last night, i soldered the black wire on the metra kit to the black wire on my new stereo harness... that means that the ground on my stereo connects to the black wire on the factory harness... any idea where this goes? is this even a ground point? my DVM apparently broke itself between uses, so i couldn't probe to verify last night

mbentley

iTrader: (1)

This is something that I am considering doing as well. I'd like to know what would be the best method of which to add the resistors that will last. I'm a novice when it comes to soldering, that's for sure

firebirdude

iTrader: (3)

The pdf shows to use 1/4 watt resistors. If you're worried that they're going to burn up, you can always use 1/2 watt or higher if you want.

And just so we're clear, this is 3 resistors PER SPEAKER. So you'll need 12 total. Soldering them shouldn't be hard, but insulating all this while crammed behind the dash might not be fun.

mbentley

iTrader: (1)

I'm a complete idiot when it comes to resistors and whatnot. Reading that drawing, what does 62, 5%, 1/4w mean? I am assuming that the % is the tolerance within actual value, the third value is watt rating? Is the first number the ohms rating of the resistor? I'm trying to figure out what resistors I would exactly need to try this out.

ccrooks

62 ohm, 5% tolerance, 1/4W rating, correct

for me, installing/insulating shouldn't be THAT big of a deal... i'm considering buying some shrink-wrap and sealing the whole works up that way

every minute that this goes by, the scope of my project grows

ccrooks

oh yeah, and while i'm at it, this diagram shows that there are 2 grounds (P and S... i'm guessing power and signal) in the factory harness for the stereo. i'm going to check to make sure that P Ground is connected to chassis ground. if so, i don't see any issue connecting the ground for my new head unit to this, do you?

firebirdude

iTrader: (3)

I really don't remember what I used for a ground. May have been the stock harness or maybe I made my own. It's been too long...

And your read on the resistors is correct. When you buy them, they'll obviously be bagged/marked, but you should know how to read them as well.

It would be super simple for someone to slap these on a PCB with some speaker terminals at very little cost. It would be far easier to insulate and install them this way too. And I'm sure you'd have no problems selling a few either. I've been PMed by like 5 people this past week alone pertaining to this. ........ but no. I'm not interested in making them. :P