14 sub/amp install with bose, problem

[Big_D]

Just hooked up and installed some stereo equipment. Built a custom box w/amp space, sealed w/x2 10" flat hertz subs, hertz 1D amp, hertz remote bass knob. Have bad feedback noise with the engine running..

 

Bit of install info--

-this amp does 700w rms @2ohms, 10% THD, but i'm going for sound quality.

-so, i set the gain for 550w rms @2ohms for less than 1% THD.

-if anyone is unclear about gains, the equation for measured voltage off the speaker out terminals on the amp is V=squareroot of [power x resistance]

-so in my case 550x2=1110. Square root of 1100 is =33.17VAC

-turn off all EQs on radio/source, play 50hz sine wave and adjust gain to calculated voltage..

-spliced the stock blue(+) and grey(-) sub leads into the high level speaker inputs on the amp. Amp has auto on feature so i didn't bother with the remote wire.

 

These subs sound very nice after tuning. If the truck is off, I can listen @3/4 volume distortion free. Brief listening, but quite impressed. How i have missed bass! So disappointed when I went to show the wife my hours worth of work when i start the truck up and hear immediate feedback/noise..

 

Options I'm looking at now are either, installing a LOC and bypassing the auto-on/high level inputs.. or disconnecting the ANC mics? Any help is appreciated. Thanks.

 

 

[rockyridge26]

Install a loc problem fixed!! Loc on all amps are junk 80% of the time they will give you ground noise. This what I used for my install last weekend and it Jams really clean sound!!

PAC SNI-35 Variable LOC Line Out Converter https://www.amazon.com/dp/B001EAWS3W/ref=cm_sw_r_awd_QJJlvb0RXR5NK

https://www.amazon.com/dp/B001EAWS3W/ref=cm_sw_r_awd_QJJlvb0RXR5NK

[austingta]

I used this:

 

http://www.amazon.com/AudioControl-LC6i/dp/B002T4XR78/ref=sr_1_2?ie=UTF8&qid=1429096229&sr=8-2&keywords=audiocontrol

[Big_D]

Ok I'll grab a LOC today. Do you guys have a 6.2 w/ANC?

[austingta]

Mine is a 5.3

[steven.fararre]

I just made sure I had a perfect ground no paint st grounding point. Result no engine noise.

[austingta]

The rear seat belt bolt is a perfect ground.

[Big_D]

not really engine noise or alternator whine. i know the ground is good. used a rear seat bolt as well, just ground off all the paint. really seems like the mics are affecting it. i can turn the volume on the head unit all the way down and the subs start loudly humming away.

[Stoddard]

From what ive heard on past active noise issues, is to disconnect the rear speaker only. I have no experience with this though. I do want to know what to do as I have a '15 6.2 and want to add subs.

[Big_D]

anyone have a schematic for the bose amp/pinouts in these trucks? would like to try disconnecting the mic, or mics without cutting the connection in the headliner area... but it may come down to that soon

[Big_D]

FIXED. Cut the violet/blue wire in the rear passenger side door tray(where i spliced into the bose sub wires). It's the crankshaft position sensor replicated signal wire. Cut this, disabled ANC. I imagine it supplies the amp with the engine load/rpm info for ANC. Went for a drive after cutting and capping this wire, no more annoying feedback. Shout out to Rush on tahoeyukon forums for finding which color wire to cut.

 

 

[Bvonscott]

This is the same problem I had. I knew active noise cancelation is the cuplrit. although I have not finished the install yet. Now I can thanks.

[Big_D]

Hope this helps anyone else with this issue.

[tsdrumm]

FIXED. Cut the violet/blue wire in the rear passenger side door tray(where i spliced into the bose sub wires). It's the crankshaft position sensor replicated signal wire. Cut this, disabled ANC. I imagine it supplies the amp with the engine load/rpm info for ANC. Went for a drive after cutting and capping this wire, no more annoying feedback. Shout out to Rush on tahoeyukon forums for finding which color wire to cut.

 

 

Nice. So you just cut that wire?

 

Are those the taps to the Bose that you made beneath the screw driver in the pic? The grey/black and blue/white? Are those the high level inputs of your amp?

[Big_D]

Nice. So you just cut that wire?

 

Are those the taps to the Bose that you made beneath the screw driver in the pic? The grey/black and blue/white? Are those the high level inputs of your amp?

yes, just cut it.

 

twisted thicker wires run to the existing bose sub, dark blue/grey is positive, grey/black is negative. spliced these into the high level inputs on the amp.