2020 RAM Laramie 4WD Audio System Build w/ 12" Display and JL Audio Stealthbox

[392DCGC]

Measured from my iPhone 11 Pro in MLP. Not sure how accurate, but the graph seems pretty telling to what my ears hear. When I measured my home theater system with Audyssey set to reference, the graph looked excellent. The changes I make with the EQ in the truck immediately reflect in follow-up tests on this graph as well.

Stock


Infinity (Dash) & PAC/Kicker amp hooked to stock subwoofer - Bass +5, Mids +4, Treble +1



FaitalPRO (Dash) & PAC/Kicker/stock sub, now with Poly-Fil, butyl rubber behind the box, & acoustic foam along rear wall - Bass +5

Kinda looks like the Poly-Fil reduced the sub’s output below 30 Hz.

 

[Sonnie]

Not bad at all really. If you get a chance to unplug your sub and measure with all EQ bands at 0... then we could compare it to what I measured.

That peak at about 100Hz on the first graph could very well be the boominess I was hearing.

 

[392DCGC]

Not bad at all really. If you get a chance to unplug your sub and measure with all EQ bands at 0... then we could compare it to what I measured.

That peak at about 100Hz on the first graph could very well be the boominess I was hearing.

Yep, I could easily do that since it's running on the Kicker amp now. I'll give that a try tomorrow hopefully.

So obviously I put the FaitalPROs in my dash today. I think I’m on the same page as you - the Infinity’s are noticeably lacking in the highs even though my graphs don’t show it, but my ears certainly heard it when doing the same fade L/R test with one of each installed. After swapping the whole set, music is brighter than it was before, but not to the point of being harsh (my EQ for treble is set +1). I currently have the mids set +4 to lift up that trough in the 800 Hz-1.7 Khz range. I can post another graph with my EQ settings as well. I ended up using metal snips to get them to fit. Took about 20 seconds per speaker once I figured out exactly how to fit them. I will say the stock mids/tweeters push higher much stronger. Past about 16 Khz, the Faital & Infinity roll off but the stock speaker keeps on truckin'... and now that I mention it, you can see that on my graphs! The aluminum dome tweeters in the stock speakers can push higher with more volume, so that tempts me even further to leave them be in the front doors to help keep the soundstage wide. Before with the Infinities, because of their lower volume, at times I could pinpoint high notes coming moreso from the door speakers. I think the Faitals have alleviated this since they are a bit louder, and more detailed in the highs. As far as the rear roof... I swapped those out on my 2019 and didn't notice a difference up front whatsoever. Not sure if the juice is worth the squeeze on that one. But if you happen to swap them and report otherwise, maybe I'll give it a shot again.

 

[Sonnie]

If you think about the difference when comparing just one speaker... you hear it, maybe only a slight difference, but then when you replace all three and multiply that difference times three, you hear it even more then.

 

[Sonnie]

Here we go.... Bass EQ band set at -9... as we have already determined it does not effect the dash speaker since it is high-passed at 300Hz.

The first graph shows response measured at the speaker mounted in the dash. The factory speakers is surprisingly very flat, although at the speaker is not where it matters most.




The second graph shows the response with the mic at the head area of the driver's seat... center of where my head would me. This will vary somewhat based on how your seat is adjusted and where your head is located, so this is not the end all of the response you will hear, but it will give you a fairly good idea of the comparison of the speakers.



There is approximately 12dB difference between the factory speaker and the Infinity at 2kHz... and a fairly nice trough between 600-2kHz, which is why some of us are noticing such a drastic difference. Again, the factory speaker is the smoothest among the three. I suspect it was designed this way and/or there is EQ applied in the DSP portion of the amp. I suspect the harshness of the factory speaker comes from the bump at 2.7kHz. That area right around 2.5kHz can be shrill, while 4kHz is not near as bad (at least not to me). I did not test it, but if you have the Infinity, you could bump your mid EQ band up to +7 to +9 and get several dB closer to factory, as you'll get about a 3-6dB boost from 400Hz - 3kHz... which is the area most affected above. And you could bump your high EQ band up to +4 to +6 and it would be all that terribly far off altogether.

The area above 13kHz matters not to me, as I have already proven in testing that I can't hear the first thing above 12kHz, and I have to have my ear right up near the speaker to hear 12kHz. Several of us guys tested our hearing (unofficially) during one of our speaker evaluations and none of us could hear much of anything above 11-12kHz at any respectable level.

 

[392DCGC]

A few more from me. 6x9s are factory with no deadening material applied to the doors. Faitals installed in the dash, mids +4 treble +2, volume set 20 for all.

Subwoofer disconnected, bass +0


Subwoofer disconnected, bass +5


My best effort to get a flat curve in the bass response with the subwoofer connected and bass boosted a bit. Reminder again that my factory amp isn’t sending a signal to nor powering the sub - using the PAC for signal & a Kicker amp.


I’m pretty surprised by this. I had thought I remembered the factory sub reaching down audibly to 19 Hz when 100% stock, but that’s not the case with my current setup when I manually input frequencies. The sub and 6x9s lose basically all output below 27 Hz. And the sub doesn’t really seem to be adding much of anything! With a bit of amp gain/crossover tuning, I was able bring up that dip at 125 Hz using the sub, but the sub either introduces a slight dip around 63 Hz that doesn’t exist when only using the 6x9s, or it’s just not capable of outputting as equally at that frequency. Now I’m a bit mad at myself for the effort and cash thinking I needed the factory sub, when that doesn’t seem to be the case. The factory 6x9s are quite strong when you EQ the bass up. I would need to change something in my setup to get the sub to output lower, and I’m not willing to sacrifice any interior storage space, so the factory sub is what I’m left with. Still, I thought I remembered it reaching lower - maybe the PAC or Kicker are rolling off the deep bass sooner than the factory amp did?

I can clearly hear all the way up to 18 KHz from MLP, probably because my ears are still relatively young.

 

[Sonnie]

Yeah... wait until you get on up in your 50's and have listened to loud music for 30 years... it will start to diminish. Mine started going in my 40's... from listening to extended periods of 140dB+ music in my vehicles. Now I have tinnitus and can't hear much above 10kHz... thankfully I'm not missing all that much.

The factory 6x9's are really good in this vehicle, as you can see. The sub just doesn't do much on its own, other than create some cancellations (standing waves) resulting in frequency irregularities, although probably not that noticeable. However, you can at least make some adjustments to the sub to help help with the response, whereas you can't without out. That response is still not bad for what you are running. I'd say very acceptable actually. I don't think the Kicker would roll off, unless you have a low frequency roll-off adjustment (subsonic filter).

 

[392DCGC]

Yeah... wait until you get on up in your 50's and have listened to loud music for 30 years... it will start to diminish. Mine started going in my 40's... from listening to extended periods of 140dB+ music in my vehicles. Now I have tinnitus and can't hear much above 10kHz... thankfully I'm not missing all that much.

The factory 6x9's are really good in this vehicle, as you can see. The sub just doesn't do much on its own, other than create some cancellations (standing waves) resulting in frequency irregularities, although probably not that noticeable. However, you can at least make some adjustments to the sub to help help with the response, whereas you can't without out. That response is still not bad for what you are running. I'd say very acceptable actually. I don't think the Kicker would roll off, unless you have a low frequency roll-off adjustment (subsonic filter).

Yeah that’s something I avoid. Your posts saying you push the volume all the way to 30 blows my mind lol. I use my Apple Watch to get dB readings if I think it’s too loud. 99% of the time, I don’t go over 85 dB which is usually around volume level 20 when sourcing from my iPhone. I have tinnitus as well thanks to blasting music through headphones as a kid and the military not teaching me how to properly use hearing protection with firearms when I was younger. I try to take better care of my hearing now.

 

[Sonnie]

Installed the rear headliner FaitalPRO speakers today, while waiting on my windshield to cool to treat it with Optimum Opti-Glass Coating.



I really would like to wire them for rear fill, but I'm afraid I might damage the amp since I would be attempting to bridge those amp channels...

Amp Left+ to Speaker Left+
Speaker Left - to Speaker Right-
Speaker Right+ to Amp Right-

However, no way to add the delay.

At this point, I have wired them out of phase to see if that will help any... probably won't.

 

[Sonnie]

Did some more comparisons.

Got the CDT speakers in. Installed them in the front. Long story short... not any difference to note in the response or volume level at the same setting, but they will no doubt handle louder volumes with less distortion. Worth it if you crank it up a good bit, which I do. They are much beefier speakers and don't require a lot of power to drive them, as evidenced by the same SPL at the same volume setting.

Also installed the FaitalPRO's in the upper door, which made a little difference in the top end.

Here are some comparison pics and graphs.

 

[Sonnie]

Then... just for kicks... I found a pair of JL Audio CS2-350x speakers I forgot I had, from a system a couple of years ago that I did in a vehicle. I measured one of those against the FaitalPRO. If you plan on using these, you'll want external power to make them sound their best. The vocals disappeared otherwise.

 

[Sonnie]

I believe it is worth noting that during my 25 minute drive to the shop this morning, I was playing some of my favorite Yello tracks, which have some interesting bass good for testing a car system. I am fairly certain I notice the CDT exhibit no stress at louder volumes, whereas the factory speakers did have a limit where I noticed they were beginning to stress and I'd have to back off the volume. No backing off with the CDT, they seemed to play much more effortlessly, which they should, being a better built speaker with considerably more xmax.

I currently have all EQ bands set to flat, fading about 3 notches to the front (so the back door speakers are not producing as much) and the surround turned on, which seems to bring the stage to the front better, without any other adverse effects that I can notice. I am very pleased with the sound, but still missing that lowest 1/2 octave on some songs, which the JL Audio Stealthbox should take care of. Lord willing... I'll be picking it up today. Even though I like to fade to front to get a better front sound stage, I will go ahead and replace the rear door speakers with the CDT's to hopefully eliminate any potential distortion from the rear speakers.

 

[Sonnie]

I STAND CORRECTED!!! At least I think I do. I stated that I did not think the subwoofer in the HK system with e-Torque is used for ANC due to what others had said about not having any issues tapping into the subwoofer speaker leads to feed their aftermarket sub amp. I now believe it may be used.

I finished up the Stealthbox install yesterday, and tonight my wife and I drove about an hour to do some shopping and take care of a few errands. I started noticing the old dreaded drone noise. The entire time I was thinking, why am I just now noticing that I may not have connected the door speakers correctly. Then I got to thinking... is what I am hearing from the sub. So I turn the headunit volume down, turn the sub control up... sure enough, it's from the sub. When I am driving 55 and let off the gas to coast, hear it comes, very pronounced. I can turn the sub off, no noise... turn it back on, it's there. If I press the gas pedal again, it goes away. It pretty much has to be the ANC kicking in, but for the life of me, I can't figure out what noise it is trying to combat, because when I have the sub turned off and let off the gas to coast, I don't hear a thing. Of course I am FAR from knowledgeable about how the ANC works, and it may not be this, but it makes sense that it is. The JL amp is amplifying the ANC signal to the sub when the sub is turned up, and it gets louder as the sub level increases.

THEREFORE... at this point, I cannot recommend using the subwoofer speaker leads to feed into a JL Audio LoC-22. I can't speak for feeding into high-level inputs on an amp (my amp does not have high-level inputs). I know of at least one member here that is using the sub leads into his amp and claims no noise, but I don't remember what system he has. I also did not check the polarity of the sub, which may resolve the issue. If reverse polarity resolved drone noise in the door speakers, it may very well take care of it for the sub... I will check and see. OTHERWISE... I will pickup a PAC AmpPRO and run thru it instead of the LoC-22 and that should work, as it worked for me in my 2019 without having to disable the ANC. The PAC bypasses the ANC/factory amp... whereas the sub leads do not, so it makes sense the sub is being used for ANC, although I suppose it could be something else, but I'm doubting it and believe it is indeed the ANC. I'm going with that until and if I can prove otherwise.

Oh... and here are the pics of the Steatlhbox and amp install...

 

[bfhawki]

Thanks for all the info about the JL stealth box and the loc. I am anxious to see how you fix this problem. I emailed JL Audio to see if this box was going to be available in the light brown color and they said no. I asked them if I could custom order it that way and he said very unlikely. Surely, who ever is covering the box, could walk over and get some brown material instead of black. I have used JL Audio subs in my last 4 vehicles. This is frustrating.

 

[Ellisstrong]

Thanks for all the info about the JL stealth box and the loc. I am anxious to see how you fix this problem. I emailed JL Audio to see if this box was going to be available in the light brown color and they said no. I asked them if I could custom order it that way and he said very unlikely. Surely, who ever is covering the box, could walk over and get some brown material instead of black. I have used JL Audio subs in my last 4 vehicles. This is frustrating.

You can get a box made that matches your interior with JL subs for around the same price as this box

 

[Sonnie]

It also shouldn't be all that difficult to remove the carpet on the box and replace it with the matching color... you could probably find a color that would match closer anyway.

I have ordered the PAC AmpPRO R.2, optical input module and an optical cable from Crutchfield that will arrive on Wednesday, but it may be next weekend before I can get it swapped out. It will be better to have a cleaner signal sent to the amp anyway. I should have done this from the beginning, but was trying to avoid having to worry with it. The LoC would have been easier, but it definitely does not work for this truck and this install.

 

[bfhawki]

Thanks for the replies. Ellisstrong, are you talking about the MTI boxes? The reason I want the JL box is that it doesn’t stick out to far like the pics of the MTI boxes I have seen. They do look great and look very well built. I have looked on their website and didn’t see one that doesn’t get out over the floor mat.

Sonnie, I will be watching this thread to see if the Amp pro fixes the problem. Do you think I you are going to like the JL box once you get it dialed in?

I have already bought the CDT 6X9’s and the Faital Pro’s and my truck hasn’t even got here yet. It is built but waiting shipment. A bright white Longhorn with the light brown interior but no filigree stitching.

 

[Sonnie]

You are right about the MTI boxes, I'm not sure they can make one with 10's that won't stick out as far. My previous MTI box with a pair of 10's was as shallow as they claimed they could get it. Not sure why they can't duplicate JL's box (or something similar) so that it doesn't stick out as far. I like their finish... very nice. The JL box looks nice as well, but it's not as smooth and elite looking as the MTI.

The JL box sounds incredible... no doubt I'll like it. I have it fairly well dialed in now, but have to put up with drone when driving. The TuN software really makes it nice to dial in the sub response.

I think you'll like the CDT/Faital combo. I am working on seeing about getting the 4" Faitals installed. Not that it will matter, just that I challenged myself to at least see if it can be done.

 

[bfhawki]

With the Amp PRO, when you use the optical cable and module, it takes place of the rca cable to connect to the amp?

 

[Ellisstrong]

Thanks for the replies. Ellisstrong, are you talking about the MTI boxes? The reason I want the JL box is that it doesn’t stick out to far like the pics of the MTI boxes I have seen. They do look great and look very well built. I have looked on their website and didn’t see one that doesn’t get out over the floor mat.

Sonnie, I will be watching this thread to see if the Amp pro fixes the problem. Do you think I you are going to like the JL box once you get it dialed in?

I have already bought the CDT 6X9’s and the Faital Pro’s and my truck hasn’t even got here yet. It is built but waiting shipment. A bright white Longhorn with the light brown interior but no filigree stitching.

I feel like if they can make mine with 3 10’s and it only is on top of my mats in the middle where the 3 subs are I can’t understand how they couldn’t make one for 2 10’s that angled back behind the mats like the JL ones. Have you reached out to them directly?