Budget hidden sub with HK sound system

[myles]

Pretty straight forward project, but I haven't seen anyone add an additional sub BEHIND the seats, always under them. So i figured I would post...

Goal: add more bass without sacrificing cargo space

sub: JL Audio ACP110LG-TW1 --- 400w sub 10" sub w/ amp --- bought used off of offerup for $240
wire: 6 AWG power/gound wire from local welding shop: $43
JL Audio bass knob: $50 - haven't gotten this yet but it is a must for me, there is so much bass at low volume its not even enjoyable.
total: $333 for a darn good bass setup that is heard but not seen!

So that sub/amp combo is too big so I chopped it down to 17", re-glued everything and it fits perfectly.
final box dimensions: 17" x 13.5" x 6.75"

This was my 1st time ever doing anything with audio equipment, but it was pretty easy.
For a signal I tapped into the factory HK sub.

Sounds great at 3/4 to max volume, honestly more bass than I need, so I need to get the volume knob to listen to it any lower than that.

Edit: I did have to recline the seat a couple notches, which is how I kept them anyways so it made no difference to me. With the seats all the way in the upright position the seat would not latch into the back.
edit2: added pics and the bass knob

 

[antwon412]

Did you have any pictures to go with this? I’d like to see how it all came out. Thanks.

 

[myles]

Did you have any pictures to go with this? I’d like to see how it all came out. Thanks.

Once I get off work ill post some pics

 

[LaxDfns15]

Did you run an LOC off the sub inputs to have RCA inputs to the new sub? I've been thinking about doing something similar. I had subs running off an LOC from my stock system in my old truck for years before I went aftermarket. Had 3 subs total including the OEM.

 

[myles]

Did you run an LOC off the sub inputs to have RCA inputs to the new sub? I've been thinking about doing something similar. I had subs running off an LOC from my stock system in my old truck for years before I went aftermarket. Had 3 subs total including the OEM.

Didn't use a LOC, the sub/amp had a high level input option so I just used that. An added benefit is that it doubles as the switch/ignition, so I didn't need to run a remote wire.

 

[mikeru82]

For a signal I tapped into the factory HK sub.

Exactly how did you tap into the factory sub? I'm assuming you wired your new sub in parallel with the factory sub. You really need to be careful when doing this, as you have changed the impedance on the subwoofer channel. You effectively cut it in half, which could overdrive the circuit. I have no knowledge about the audio design on these trucks, and what you did may not cause any problems. But I would try to find out before modifying any of the circuits. You said it's your first time working with audio equipment. I would suggest you give yourself a crash course in wiring audio equipment in general. And for now you may want to disconnect that extra sub, at least until you determine if you'll blow that circuit or not.

 

[myles]

Exactly how did you tap into the factory sub? I'm assuming you wired your new sub in parallel with the factory sub. You really need to be careful when doing this, as you have changed the impedance on the subwoofer channel. You effectively cut it in half, which could overdrive the circuit. I have no knowledge about the audio design on these trucks, and what you did may not cause any problems. But I would try to find out before modifying any of the circuits. You said it's your first time working with audio equipment. I would suggest you give yourself a crash course in wiring audio equipment in general. And for now you may want to disconnect that extra sub, at least until you determine if you'll blow that circuit or not.

Ok so I did some googleing and most of it is gibberish to me. But it seems the general consensus says its OK as long as you're not using the factory wires to actually power the amp, just using it as a signal.

And then this is from the JL Audio manual in the high-level input section.
"The amplifier will attenuate the high-level signal and make it compatible with its input stage."

I don't see why JL Audio would put that in their manual if they knew it could fry something.

 

[piening2150]

Exactly how did you tap into the factory sub? I'm assuming you wired your new sub in parallel with the factory sub. You really need to be careful when doing this, as you have changed the impedance on the subwoofer channel. You effectively cut it in half, which could overdrive the circuit. I have no knowledge about the audio design on these trucks, and what you did may not cause any problems. But I would try to find out before modifying any of the circuits. You said it's your first time working with audio equipment. I would suggest you give yourself a crash course in wiring audio equipment in general. And for now you may want to disconnect that extra sub, at least until you determine if you'll blow that circuit or not.

He added a powered sub, so he's just tapping it for signal to the amp section, which means it won't affect the OEM sub or amp adversely.

 

[myles]

Did you have any pictures to go with this? I’d like to see how it all came out. Thanks.

Here are some pics,
I installed a bass knob in the driver seat

 

[Diamondback]

Nice writeup. I shoulda posted all of mine I did last month as well. I forgot to take as many photos LOL

Tim N

 

[antwon412]

Very nice. And I have to say I love the color of the interior. I don’t understand why so many trucks and cars have to have a solid black interior. The tan brown gray colors are so much nicer. Make the truck cabin feel so much more open and airy

 

[mikeru82]

He added a powered sub, so he's just tapping it for signal to the amp section, which means it won't affect the OEM sub or amp adversely.

In that case, carry on. I wasn't sure so I figured I'd ask. I haven't done car audio for years, and a lot has changed in that time.

Very nice. And I have to say I love the color of the interior. I don’t understand why so many trucks and cars have to have a solid black interior. The tan brown gray colors are so much nicer. Make the truck cabin feel so much more open and airy

You're right, they look great...when new. But look at some of the older cars and especially trucks with lighter colored interior and you might not like what you see. I've owned cars with just about every color that was ever available, and nothing hides dirt, grime, stains, etc...like black does.

 

[Neurobit]

You're right, they look great...when new. But look at some of the older cars and especially trucks with lighter colored interior and you might not like what you see. I've owned cars with just about every color that was ever available, and nothing hides dirt, grime, stains, etc...like black does.

^^^ This ^^^

 

[antwon412]

I don’t know. I had a 10 year old F150 I bought used and the tan leather interior was super clean. Previous owner must’ve just really taken care of it.

 

[Neurobit]

I don’t know. I had a 10 year old F150 I bought used and the tan leather interior was super clean. Previous owner must’ve just really taken care of it.

For me that keeping it clean wasn't the issue, it was the effort involved to maintain it. Light colored seats require a lot more diligence to keep them from getting stained. Specially denim transfer on the seats. Same with light carpets.

On the other hand, on my black leather seats, all I need to do is give them a wipe when doing the interior and done.

Cheers,

 

[392DCGC]

Going to share some things I've learned along the way.

1. Did you disconnect the factory sub? If not, you should.
2. You need to disable active noise cancellation if you're going to tap into the high level sub signal, or else you'll potentially be getting drone through your aftermarket sub.
3. The HK amplifier is tuned poorly for the subwoofer channel. The bass is insanely boosted and there's nothing you can do to change that. If you want a clean, flat signal (which you can then EQ yourself to taste), you'll need to use something like a PAC AP4-CH41 to hook up behind the screen and send an RCA low level signal to the amp... I tried the powered subwoofer/high level input route just like you, and it did not impress me because the factory amp is EQd like ****. Sending a flat low level signal was the only thing that sounded good to me.

 

[myles]

Going to share some things I've learned along the way.

1. Did you disconnect the factory sub? If not, you should.
2. You need to disable active noise cancellation if you're going to tap into the high level sub signal, or else you'll potentially be getting drone through your aftermarket sub.
3. The HK amplifier is tuned poorly for the subwoofer channel. The bass is insanely boosted and there's nothing you can do to change that. If you want a clean, flat signal (which you can then EQ yourself to taste), you'll need to use something like a PAC AP4-CH41 to hook up behind the screen and send an RCA low level signal to the amp... I tried the powered subwoofer/high level input route just like you, and it did not impress me because the factory amp is EQd like ****. Sending a flat low level signal was the only thing that sounded good to me.

1. left the factory sub connected, I like the sound of it, it just didn't have enough oomph for me.
2. there hasn't been any droning issues with noise cancellation, maybe its a 2019 issue? not even sure if my truck has it, I don't have any mics besides in the front seats and i think those are for phone calls/Siri?.
3. sounds good enough for me, not a audiophile/bass head so I doubt I would even be able to tell the difference, I installed the bass knob so I can turn the bass up and down as needed.

overall I am very happy with how it all turned out, and very easy to install.
And coupled with the fact that i sold the subs and amp from my old truck for $300 I couldn't ask for this to be any better.

 

[myles]

For me that keeping it clean wasn't the issue, it was the effort involved to maintain it. Light colored seats require a lot more diligence to keep them from getting stained. Specially denim transfer on the seats. Same with light carpets.

On the other hand, on my black leather seats, all I need to do is give them a wipe when doing the interior and done.

Cheers,

very true, new blue jeans leave a blue tint on my seat, even my old jeans turn the leather blue after a while.
once a week i wipe the driver seat with a leather cleaner/conditioner. Only takes 30 seconds to clean and I just do it while im cleaning the entire interior.

 

[Sonnie]

Very interesting... I think all of the 2020 Laramie models have ANC, which makes it even more interesting that you are not getting any adverse effects from the ANC system. Also... that HK sub has 6 wires connected to it... triple voice coil, so it's 3 pairs of wires. There are two pair for the full sub response, and another pair for the ANC response. Can you tell me which two you tapped into... the colors please?

The factory HK sub is nasty boomy. I have to move the EQ bass slide to -9 in order to being able to think straight while listening to it. I can't imagine anyone liking it. Perhaps the aftermarket sub is cancelling out some of those frequencies and making it less boomy. I would love to see the response with a program like REW showing the before and after response, but that would likely be more than you'd care to fool with.

 

[Diamondback]

Very interesting... I think all of the 2020 Laramie models have ANC, which makes it even more interesting that you are not getting any adverse effects from the ANC system. Also... that HK sub has 6 wires connected to it... triple voice coil, so it's 3 pairs of wires. There are two pair for the full sub response, and another pair for the ANC response. Can you tell me which two you tapped into... the colors please?

I believe you are confusing the Challenger Dual sub with the RAM sub.
The RAM sub is a single speaker - single coil - 1 pair of wires:
GREEN + BLACK

The Challenger Dual setup that you described has 3 pairs (2 dual-voice coil subs but only using 3 of the 4 inputs):
BLU + YLW
RED + TAN
GRN + WHT

See my previous posts with images I also posted recently.