Thoughts on this setup

Scott4957 · June 10, 2016, 12:17:43 PM

Bang....or BOOM for the buck whats your thoughts? I haven't pulled the MKS apart in the back yet but there is obviously a sub in the center of the rear deck with the THXII system. There is a big dished part of the cover in the trunk, I am sure I can make that sub fit and it can be ran free air. Can the electrical system handle this without any dimming or other weirdness? I used to do a ton of car audio back in the day and we had to run caps, those where much larger systems and we didn't have the efficient Class D amps like this one.

https://www.amazon.com/AudioControl-2-Channel-Converter-Subwoofer-Control/dp/B01EDFPNSG/ref=sr_1_1?ie=UTF8&qid=1465573155&sr=8-1&keywords=audiocontrol+lc2i

https://www.amazon.com/Rockford-Fosgate-R500X1D-1-Channel-Amplifier/dp/B00BF6HYDE/ref=pd_sim_107_2?ie=UTF8&dpID=51m3QK2fvWL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=GHWZK44NTA1HK79S23A0

https://www.amazon.com/dp/B002MXQAAC/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=3HSH0HBS6W5TL&coliid=I40FSVF52GAMP

iceberg65 · June 10, 2016, 12:42:03 PM

I am running an Lc2i and a alpine pdx 1000.1 in my SHO and it works well. The alternators in these are very stout; 175a or 200a from what I can find. Regardless the 1000w amp didn't bring out any odd electrical stuff. Dont use caps, they arent needed and can put extra strain on an alternator.

The Lc2i is quite good as far as a LOC goes, good bang for the buck but still not the same quality as a dedicated headunit output (but thats not really feasible in these cars so its a great option for not a ton of money)

As for running the sub free air; make sure you use a sub thats made to run free air or you will be disappointed. I dont have much hands on experience with this part of it. I always just use a box. I set mine up so that its easy to remove if you know how to get it out. and the amp is mounted behind the trunk carpet above the shock tower. (the pdx is small)

sholxgt · June 10, 2016, 12:51:51 PM

I will be curious to see what you find as I would also like to increase the bass response while keeping the factory locations.

My limited research found that the factory sub in our MKS' are 12", but I have not dug in to find out yet. I think they are dual voice coil speakers.

The THX is supposed to have 700 watts total. I would guess that a large portion of that is going to the sub. Given that, my plan is to try replacing the factory subwoofer with a quality free air sub first and then see if it needs additional amplification.

The free air style is definitely a compromise. I've only had one friend pull it off successfully. He had 2 12's in the deck of a car with a small trunk and he sealed the deck and seat backs. At that point, the subs basically had a "box." With the size of our trunks, I'm not sure a free air will ever be that great.

sholxgt · June 10, 2016, 01:27:40 PM

Just wanted to chime in more now that work cleared for a minute...

I suspect that the cover/baffle under the sub is to designed to "shrink" the trunk size as far as the sub is concerned. It would slow the airflow and create some resistance. I've had two thoughts for that baffle...
1. try to make it work better by either sealing with dynamat or stuffing with poly fill.
2. replace entirely and build a lightweight box. Hang and seal it to the deck under the factory location.

Overall, I'm extremely disappointed in the THX sound system. It is not up to par with other THX systems in other Lincolns or even systems in less expensive cars. I hope that improving the sub will make the whole system sound better, but I'm not sure. I've read that disconnecting the center dash speakers improves sound quality, but I use my Sync, nav, blutooth, etc daily, so I'm not sure that's a good option for me.

Curious about the audio controller with line out input. Can't you just buy an amp that accepts line out inputs instead? I don't think it would add anything unless you also purchase the remote control. This will be the first time I've tried to modify a factory system so my knowledge is very lacking. I'm used to just ripping EVERY factory component out and replacing.

glock-coma · June 10, 2016, 02:03:21 PM

Not sure how different the trunk area of the MKS is compared to the SHO but I'm currently running 2-15"
Subs free air. I using a jbl ms-8 processor with all active front speakers.
I haven't quite dialed in everything yet but it sounds pretty damn good.
I was going to do a build post soon. Just need to get all my pics together.

sholxgt · June 10, 2016, 02:11:39 PM

Can't wait to see glock!

The MKS has full range speakers in the rear deck as well. Did the SHO? Did you remove those? Only front stage and no rear?

I can see that 2 15's would be the way to go with the size of the trunk. I bet that thumps!

Scott4957 · June 10, 2016, 02:32:29 PM

Well I sure hope I find a 12 when I open it up, that would be great if I had that space. That Infinity is approved for free air, I just need to do some research and see if anyone is running it that way and how it sound. I had the exact same thought about building a sealed box that would mount to the rear deck and take the place of the baffle. Seeing that many of these subs are looking for .65-.75 it would not be large at all and I am not worried about a few extra pounds. This particular LOC will give far better quality than the line in options on the subs as well as better control. I suppose I can always mount it free air and if I don't like it build the box as described above.

Scott4957 · June 10, 2016, 02:46:20 PM

I found that the 2012 and below is a 10" sub. I assume the 2013+ is as well and the extra watts on the THXII 2013+ is just the extra channels.

glock-coma · June 10, 2016, 02:58:30 PM

Most important thing with free air is cone size, you want air displacement. You can run relatively low power and still get high spl with sq

I removed both rear deck subs and rear center.
I'm still running rear coaxial in the doors.

Scott, you can alway make an adapter to fit the 12 in the 10 spot out of mdf.

Scott4957 · June 10, 2016, 03:29:16 PM

Yeah i was just reading the spec's and Infinity says that if you run free air consider that it will only take half the rated power. Considering that I will be using 1 10" or 12" sub and that a sealed box is rather small I am going to first look at building a box that will attached to the rear deck. I am sold on that amp for a single sub, looks to be the best bang for the buck. I should have time this weekend to dig into the trunk and see what we have in there, more to come!

sholxgt · June 10, 2016, 03:34:11 PM

Take some pics if you get a chance!

I'm also curious if they did a good job sealing off the other speakers in the rear deck. We could be getting distortion from the air from the sub moving the other speakers. In other cars I've done, I baffled/sealed the other speakers from the sub and not baffled the sub. This system seems backwards to me, but I'm sure THX knows waaaaayy more than me.

I'm not sure what all is going on back there since I haven't torn into it either, but I can tell it doesn't sound good. Front stage seems good enough for my needs.

glock-coma · June 10, 2016, 05:18:29 PM

Depending how much air your subs will be moving the rear deck speakers may become passive radiators lol. That was the main reason I removed my rear deck subs and sealed everything off.

sholxgt · June 17, 2016, 11:15:02 AM

Was just reading the specs on that Infinity Sub. Looks like a good choice since it is free air capable. The only thing I would watch for is Infinity recommends not exceeding half of its rated power handling when mounting it free air. That would give it a power handling ability of 175 watts.

Just something to consider. Wouldn't want you to have overexcursion on your brand new sub.

Scott4957 · June 17, 2016, 11:18:24 AM

Quote from: sholxgt on June 17, 2016, 11:15:02 AM
Was just reading the specs on that Infinity Sub. Looks like a good choice since it is free air capable. The only thing I would watch for is Infinity recommends not exceeding half of its rated power handling when mounting it free air. That would give it a power handling ability of 175 watts.

Just something to consider. Wouldn't want you to have overexcursion on your brand new sub.

For sure, I did see that and I don't plan to drive it too hard. At half the power it will blow away the stock 10" sub. I think that stock sub weighted in at about 1.5 pounds LOL. I'm going to take is easy on the sub, let it break in properly then test its max and dial it back.

sholxgt · June 17, 2016, 11:26:58 AM

Awesome! Really looking forward to the end result. I may follow in your footsteps with a 10" sub just because I'm lazy. LOL

Do you think the 12 could have been top mounted or would it have required substantial metal trimming?

Side note...I found out the hard way with my last car to not use a cutting wheel on the rear deck. I got the whole job done and everything looked great until I found out that the sparks that the grinding wheel threw off actually made permanent melted marks in the back glass. Doh!!!