Hi there! I'm doing a self-install of a subwoofer an amplifier in my 2013 Lexus GS 350 F-Sport with Mark Levinson. I've started in on my install and I have a few questions, open to suggestions. Here's my setup.

Goals
1. More low-end bass.
2. Stay in budget. 1K.
3. Avoid permanent alterations, reversible.(Flexible on this)
4. Keep as much trunk space as possible.
5. Stealth.

Parts list
1. Subwoofer - JL Audio CS110TG-TW3 PowerWedge 10"
2. Amplifier - Alpine MRV-M500 Mono 500W x 1 at 2 ohms
3. Line Out Converter - AudioControl LC2i
4. Remote Gain Control **** - PAC LC-1
5. Amp Kit - Soundquest SQK4ANL CCA 4 Gauge Wiring Kit

Questions
1. In the trunk, which speaker wires to tap? Most folks suggest subwoofer. Other folks have suggested rears or fronts, claiming a fuller frequency. Also, which side of the amp to tap? Pre-amp (line out) or Post amp (speaker level)? Most folks are going post amp (speaker level) into their LOCs. However, some have suggested that the preamp signals would be cleaner? Tap the subwoofer speaker-out line. It looks to have all the frequency response you need. The volume up down happens in the amp. So, you must tap post amp. There are no pre-amp signals to tap. See post #6.

2. Any way to avoid the bass rolloff? I've read that our Lexus head units protect our speakers by placing a hold on the bass levels at the higher volumes. Is this true? Does this affect all speakers? No way I can tap a line that doesn't have rolloff? Does this make the LC2i AccuBass feature required for adjustment? Nope. No way to avoid it. The LC2I - or something similar - is required. Device does two things. First, it converts those high wattage speaker out wires to low wattage line outs. Second, it can combat the bass rolloff.

3. Where to get the remote on signal? I've seen folks complaining about brief subwoofer rumble when using the wrong remote on wire. There is a remote on wire going into the ML factory amp, correct? Should I just grab that, run it into the LOC, and then over to the amp? Yes. You can find a remote on wire exiting the OEM amp. Use it.

4. Thoughts on sub placement? My plan is to face the sub to the ski-hole and fire through there. Scientifically, the best sub placement for maximum bass is farthest rear. Against the license plate, facing the license plate. But, not practical. If your sub is loud enough, place it and face it where you want.

5. Where to mount the remote gain ****? Anyone got a good spot? Found one. In the little trap door by the driver's side knee. Perfect for a ****.

Thanks for any help.

END RESULTS ARE IN POST 51


Useful videos.

About the LC2i

 

I have a new to me 2014 with the same ML system. Thanks for doing the work. I look forward to your install as i will likely mirror it. I thought the 10 would be a bit better than the 8.

 

I'll take pics of my remote gain **** and set up a little later. I redid my set up because i like to take corners fast, and my box wasn't secured, and slid all over the place. So make sure you secure your box somehow, or else risk breaking rca cables like I did.

 

2. Audio Control LC2i will take care the roll off.

4. It's usually always best to face sub towards the rear of the car because the bass will gain by the time it gets into the cabin.

 

Looking forward to pics. Good advice on securing the box. gives some ideas, but we can probably do better. I know a slick mount job will make this whole project worthwhile. I'll spend some time here...

So, the roll-off is on all speaker channels, pre and post factory amplifier?

 

I believe the amp controls the volume. So if you tap in before the amp, the sub is only gonna play full blast.

I don't know if the roll-off is on all channels though.

 

Thanks. Didn't know our head units were fixed level and the volume control happened at the amp. Good info. Tapping post amp it is. The question is which speakers to tap.

 

Sorry about the delay and messy car




Installer built custom box and advised facing towards the cabin for tight bass and less rattle.




Hidden sub




quick adjustments on the fly

 

Thanks for the images, popping. Might use that location for the remote ****. For your setup, you tapped the subwoofer speaker level lines? What about remote on, where'd you grab that signal?

 

The remote is plugged into my JL500 amp. for the sub, I'm not sure what was tapped. The installer did it all for me. I chose that location for ease of access, and it is pretty hidden. I could have put it in the console, but it would have cost more money, and would have been cumbersome to adjust on the fly.

be sure to post pics when you're done!

 

@poppiing.. guess I wasn't specific enough. I meant which "remote on" wire is tapped.to tell your amp and LOC to turn on. Is there a thin blue wire running from the amp to the LOC or amplifier? I was busy this past weekend, so no speaker wires tapped yet. But I did just find these ML amplifier wiring diagrams from this thread.









Looks like I'll want.



Subwoofer (+) is the #21 Red Wire on the T40 Plug
Subwoofer (-) is the #6 White Wire on the T40 Plug
ACC (Remote Turn-on) is the #8 White Wire on the T49 Plug

 

Oh i have no idea. sorry. Installer did everything for me.

 

Installed my remote level control **** today. I'm not sure what the compartment is used for, but I installed my **** in the little compartment under the dash next to the drivers left knee. Anyone know what that compartment is for? It is the remote bass control **** compartment, correct?

 

U have to watch out what speaker u tap. Best to tap a full range signal otherwise your bass will be really weak

 

Thanks for that. Most people tap the subwoofer lines. Why is that incorrect? Which speakers would you suggest to tap?