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domeasour
01-11-2007, 04:47 PM
I am looking for a document that describes specifically how the ANC system works or any documentation related to this system.

I helped my brother change his speakers (http://www.driveaccord.net/forums/showthread.php?t=5846) and now the ANC system went haywire! every time the car starts the sub woofer makes this very loud sound. They have previously changed the ANC system along with the front speakers. I wanted to know how to turn it off or disable (bypass) it, so that it doesn't make the sub sound.

Here are the specs of what was installed

Kenwood 2 Channel 600W AMP
Pioneer 4 channel 600W AMP
10" pioneer slim sub
Pioneer 4-way 6x9" speakers (pair)
Sony 4-way 6.5" speakers (pair)

Also i don't know if this is a coincidence but about 3 days after we installed it the front lights fuse blew.

perhaps :notworthy pricess might have some info? :)

James.uk
01-11-2007, 05:55 PM
>>>>Active noise cancellation system<<<<

Erm I think thats called an off switch.. :lmao: :nuts: :biggrin: Just kidding.. lmho :D

VTECaddict
01-11-2007, 06:15 PM
the ANC system uses a mic in the cabin to "listen" for excess noise and specifically for the noise/vibration caused when VCM shuts off 3 cylinders on the hybrid. when it hears this sound, the system generates sound waves that are complete opposite of the unwanted sound to in effect cancel out the sound. this sound is played back by the head unit though the speakers.

you amp is probably amplifying the reverse waves generated by the ANC. if you disabled the system, you would still hear the deep vibration/booming sound, but coming from the engine instead. has it recently started doing this or has it been this way since the beginning (your other thread is 9 months old).

Matt-Guy
01-11-2007, 06:46 PM
the ANC system uses a mic in the cabin to "listen" for excess noise and specifically for the noise/vibration caused when VCM shuts off 3 cylinders on the hybrid. when it hears this sound, the system generates sound waves that are complete opposite of the unwanted sound to in effect cancel out the sound. this sound is played back by the head unit though the speakers.

you amp is probably amplifying the reverse waves generated by the ANC. if you disabled the system, you would still hear the deep vibration/booming sound, but coming from the engine instead. has it recently started doing this or has it been this way since the beginning (your other thread is 9 months old).

There was some talk about this in the Honda Odyssey forum. They disabled it and they said they noticed no real difference in engine noise gets through. Rather they said it sounds better because the stereo is not producing it. Check it out http://www.odyclub.com/forums/showthread.php?s=&threadid=30221 there.

domeasour
01-12-2007, 02:12 PM
has it recently started doing this or has it been this way since the beginning (your other thread is 9 months old).

It did it long ago and the dealer replaced the AMC unit and the front speakers. However, since we just changed the speakers it has been doing it again.

My biggest worry is that it might harm the subwoofer, since its the only thing reproducing the sound.

greg-ster
01-12-2007, 02:38 PM
This is a '05 hybrid, right?

princess
01-13-2007, 09:41 AM
Maybe these can help..... :dunno:

princess
01-13-2007, 09:44 AM
or this

domeasour
01-13-2007, 05:53 PM
TY Princess for those diagrams, they will come in handy!

Update:

When I turn on the headlights or parking lights, there is a low buzzing sound coming from the rear speakers (when the amp is on). it is not a fluctuating sound with different RPMs, therefore it is not cause by the engine.

~90% of the time when I start the vehicle there is a low humming sound coming from the sub, which lasts about 3-4 seconds. While I hear the humming sound, if i accelerate the sound intensifies.

someone suggested that i install a Low/High Converter to replace the speaker level inputs to RCA(high) level inputs. In order to get rid of the buzzing from the rear speakers.

Any ideas? suggestions?

domeasour
01-14-2007, 12:12 AM
does anybody know where the ANC unit is located? the car is the hybrid model with navi

thanks

princess
01-14-2007, 09:35 AM
I found a bulletin....you may have already seen it... :dunno:

The component location seems to have more than one piece to the noise control system.

ZedsDead
04-08-2008, 11:59 AM
I have a 2008 Accord Coupe with the same issue.

Has anyone solved this problem (with an aftermarket stereo)? I was simply going to disconnect the microphones but it seems like this will not solve the problem. If anyone has successfully bypassed the ANC system, please please let us know how.

If not, I will when I figure it out (trial and error I guess).

Demonik
04-08-2008, 12:27 PM
just disconnect the microphones, thats what i did and my sub is fine now

if you have a buzzing/hum going on when the car is on you need to find a better ground

texan444
06-03-2008, 04:09 PM
Hi,

I live in San Antonio and my girlfriend has an '05 Accord Hybrid with this same noise problem. The dealer says the ANC system is defective and wants to charge her over $500 to replace the control module and the speakers. It sounds like your idea of simply disconnecting the microphone(s) is a good one. May I ask

1) Does the car have one or two microphones (I could only see the one in the front, but you implied there's one in the rear as well).

2) Can you tell me exactly how you got to the microphones (i.e. the exact procedure)?

3) Do you know if there's a fuse devoted strictly to the noise cancellation system? (Perhaps we could simply remove the fuse)


Thanks in advance!

ougrad1
06-12-2008, 08:52 PM
has anyone solved this yet?

BlueEnkie
08-07-2008, 07:23 PM
I am dieing to hear more about how to disconnect the two microphones in the cabin, I tried to get to them a few times but was not able to get to them. If anyone has any picture diagrams that they can share it would be very helpful.

gaviota
08-12-2008, 09:46 AM
I don't think there's ANC in the 7th gen :dunno: