2015 Yukon Denali Bose: Best signal source for LC2i and aftermarket sub?

[ameerica]

Hey everyone! I have a 2015 Yukon Denali with the factory Bose system and factory navigation/radio.


I installed a powered Rockford Fosgate 12” enclosure using an AudioControl LC2i. I tapped into the factory Bose subwoofer output after the factory amp in the rear quarter panel. AccuBASS is turned off, and I’ve already disabled Active Noise Cancellation.


Everything works and sounds great, but I’m running into something I think is related to the Bose tuning.


At low listening volumes, both the factory Bose sub and my Rockford sub are pretty bass-heavy compared to the door speakers. As I turn the volume up, the speakers increase much faster than the sub, so the bass becomes more balanced. Since the factory sub behaves the same way, it seems like this is how the Bose amp is processing the signal.


My questions are:

• Has anyone found a way to reduce the factory Bose sub output at low volume?
• Has anyone had better results feeding the LC2i from the rear door speakers instead of the factory sub output?
• If you have a Bose-equipped Yukon/Tahoe/Suburban/Silverado with an aftermarket sub, where did you tap your signal from, and were you happier with that setup?

I’m trying to avoid rewiring everything unless people have had noticeably better results using a full-range speaker signal instead of the factory sub output.

 

[Joseph Garcia]

Did your Rockford kit come with a remote volume control that you can mount in your dash area? That would be the best way to control the Rockford sub volume level at any overall system volume level (or any type of music that you are playing).

I assume that your Rockford kit has a built-in adjustable frequency filter. If it does, then you should have an input from the head unit that delivers the full audio frequency spectrum, and let the Rockford's filter do the work for the sub's operation.

For the Bose sub's volume, I believe that you can attenuate its volume in the head unit's adjustments. The truth is that you don't need the Bose sub, with the Rockford sub installed.

 

[ameerica]

The Rockford did come with a bass knob, so did the audio control line outlook converter. I use the line out of converters knob instead of the Rockford because it sounded a little bit better for some reason. I think the audio control device and adjust the base gain differently on the Rockford.

So currently right now I’m hooked up to a factory Bose amplifier coming off of the subwoofer output. I guess my question is should I tap the speaker output instead because I feel like those have better full range control less bass.

I could definitely try tapping off of the speakers and not using the line out of converter at all and going straight to the Rockford and having its low pass filter to all the work. Everyone said using the lineup converter will sound.

 

[Joseph Garcia]

Yes, it appears that you have two sequential base volume gain controls. Using both will tend to overdrive the subwoofer amp and cause distortion. If it were me, I'd to se it up, I would set the subwoofer's volume gain control to 3/4+ volume, and then I'd adjust the LC's gain control upward to the point where the the subwoofer's sound gets muddy or distorts. At that point, keep the LC's volume gain setting locked in at that point, and use the subwoofer's volume gain control as your main volume gain control for adjustments to suit the particular music being played for low sounds.

If you tap into the Bose amplifier's subwoofer output, you will be using the Bose amplifier's low pass filter for your subwoofer sound, and that is OK, as long as you adjust your Rockford's low pass filter to full clockwise direction.

I believe that in a Bose system, the door speakers do not receive the full spectrum of audio frequencies. They only receive the frequencies above the low pass filter threshold established by the Bose amp, so that the low sounds go only through the Bose amp's subwoofer output. As such, you should not connect your Rockford's input to the speaker output from the Bose amp.