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xcellr8tion
09-30-2009, 11:34 PM
Just installed an Alpine IVA-W205 in a B7 A4 to the non-bose stock setup. Used the Connects2 harness and everything plays/sounds fine....until you turn the volume up on the headunit. It starts to clip pretty bad at about 19-20 (out of 35). Any thoughts? Seems like an amp issue, but never had this problem with the stock HU. [confused]

Help/suggestions would be appreciated, thanks!

htfan
10-01-2009, 10:40 AM
Just installed an Alpine IVA-W205 in a B7 A4 to the non-bose stock setup. Used the Connects2 harness and everything plays/sounds fine....until you turn the volume up on the headunit. It starts to clip pretty bad at about 19-20 (out of 35). Any thoughts? Seems like an amp issue, but never had this problem with the stock HU. [confused]

Help/suggestions would be appreciated, thanks!

Can you tell if it happens in both front and rear speakers? (Only the rear speakers have an external amp.) Are the rear RCAs from the Connects2 harness connected directly to the HU, or are you using some sort of line driver?

I have a non-bose B7 with an AVIC and no problems.

xcellr8tion
10-01-2009, 11:32 AM
It's strange.... when I set the fade to just the rear speakers, and turn it up, no issues (though the rear speakers arent nearly as loud as the fronts). When I set the fade back to include the fronts, it starts to clip/pop. Not currently using any line drivers for the RCA's.

CKYmike
10-01-2009, 12:15 PM
Are you bose or non bose?

xcellr8tion
10-01-2009, 12:24 PM
non-bose. BTW, Mike, appreciate all the help from you and Christian in getting the right pieces for install!

htfan
10-01-2009, 12:46 PM
It's strange.... when I set the fade to just the rear speakers, and turn it up, no issues (though the rear speakers arent nearly as loud as the fronts). When I set the fade back to include the fronts, it starts to clip/pop. Not currently using any line drivers for the RCA's.

One cause of clipping can be not enough power for the volume/speakers. Do you know what power output your HU provides to the front speakers?

xcellr8tion
10-01-2009, 01:53 PM
18w RMS/50w peak. I was thinking that perhaps the deck isnt getting enough power? I know some of the older Alpines used to recommend connecting directly to your battery, but that wasnt the case here

htfan
10-01-2009, 02:18 PM
18w RMS/50w peak. I was thinking that perhaps the deck isnt getting enough power? I know some of the older Alpines used to recommend connecting directly to your battery, but that wasnt the case here

You're right... that's plenty of power to your front speakers.

xcellr8tion
10-01-2009, 04:22 PM
Any other ideas? I'm really hoping the deck isnt bad! I'll try fused-hardwiring the deck tonight, but i'm doubting that will fix anything.

xcellr8tion
10-01-2009, 10:12 PM
Alright, so I tried a number of different things, and ultimately determined that for whatever reason my headunit and the stock front door speakers just for whatever reason are having compatibility issues.

-Tried connecting the deck power direct to the battery to see if the deck simply wasnt getting enough power, but still had the same issue
-I tried switching up the speaker wiring from the deck to see if the harness was a problem, and still the same problem. I even tried playing with polarity in case somewhere along the line something was mixed up, no go.
-Tried running them from the rear channel to see if the front was a problem, still same problem
-Tried running just the left front individually, and then the right individually, and when ran individually they each worked just fine to full volume
-And finally tried connecting the headunit to two unmounted extra speakers I had laying around.... and this worked, no issues, all the way up to max volume
-Reconnected the stock headunit and it played just fine up to it's max volume

So, this one is new to me. I've done quite a few audio installs and never come across anything like this. Anyone out there have any suggestions?!?!?!

htfan
10-02-2009, 09:44 AM
Alright, so I tried a number of different things, and ultimately determined that for whatever reason my headunit and the stock front door speakers just for whatever reason are having compatibility issues.

-Tried connecting the deck power direct to the battery to see if the deck simply wasnt getting enough power, but still had the same issue
-I tried switching up the speaker wiring from the deck to see if the harness was a problem, and still the same problem. I even tried playing with polarity in case somewhere along the line something was mixed up, no go.
-Tried running them from the rear channel to see if the front was a problem, still same problem
-Tried running just the left front individually, and then the right individually, and when ran individually they each worked just fine to full volume
-And finally tried connecting the headunit to two unmounted extra speakers I had laying around.... and this worked, no issues, all the way up to max volume
-Reconnected the stock headunit and it played just fine up to it's max volume

So, this one is new to me. I've done quite a few audio installs and never come across anything like this. Anyone out there have any suggestions?!?!?!

You're not leaving any stone unturned! You've tried everything I would have. Like you, I've done many HU installs for myself and friends, but I'm also not a professional installer.

In my recent B7/AVIC install, speakers perform well at all volume levels. (My unit is rated at 14 RMS/50 PEAK.) Only thing different to note is I am running a line driver on the RCAs for the rear amp. However, don't believe that will have an impact on your front speaker situation.

We need some input from someone that has worked with your HU in other Audi A4s.

xcellr8tion
10-02-2009, 12:39 PM
anyone know the impedance of the stock front speakers on the non-bose?

MikeWire
10-07-2009, 12:51 PM
I had this problem on my B6 (also non-Bose like yours) but the rear speakers were clipping, the fronts were fine.

I used the Metra harness, and I don't know if the B7 is the same, but here's my story.

The rears and sub are powered by the stock amp, so they only need the low level input RCA connectors (should be on the harness) plugged into the RCA output in the HU (not the +/- powered lines from the Alpine harness). The fronts do need the +/- powered lines from the Alpine harness wired to the front speakers.

Not being familiar with the Connect2 harness, I don't know if that helps or not, but it sounds like you are sending too much power out, when all you need are the low level RCA connectors to send the signal.

CKYmike
10-07-2009, 01:01 PM
Try not having the front RCA's plugged in and NOT wiring the rear speakers to the harness. So youre left with only speaker wires wired for the fronts and only rcas for the rears. Your radio is possibly outputting too much signal overall and causing the clipping.

xcellr8tion
10-08-2009, 09:45 AM
Woohoo, finally figured it out! Mike - I tried exactly what you suggested early on, but still no fix. This thing has been annoying me for a week. What I never ended up realizing, is that this thing has a front center speaker. Had I known that, I probably would've figured out the issue much quicker.

Its funny, I was frustrated so started putting various speaker wire combinations together.... at one point I mixed the (+) from the left side and (-) from the front right side, and all of a sudden music came out of the center channel. In the stock harness (brown plug) I always found it odd there were 2 wires into the (+) on one side and (-) on the other, but just assumed it was something to do with the tweeters. In reality, what Audi did was bridge the front center speaker across the right and left channel. Thus the reason my deck was clipping, they were operating at too low of an impedance since you were running the three speakers off of the two channels, with one of them getting essentially bridged.

The simple solution? Snip the two wires that are leading off to the center channel (they're the two smaller wires, one is brown w/green stripe, the other is green w/blue stripe) and tape up. You can easily reconnect these later if you put the stock HU back in.

And phew - it works perfect! Thanks everyone for your suggestions and pointers! [up]

htfan
10-09-2009, 11:11 AM
Glad to hear you resolved your clipping issue.

For some reason, this impedance problem with the 3 front speakers was not an issue with my HU.

However, I just learned something from this... Thanks!