Question about 10 Speaker Setup and Aftermarket Sub

kobaltz

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I've been reading a lot of the forums and cannot find a clear answer if what I'm looking to do is even possible or ideal. I have a 2018 Civic SI with the rear 8" Subwoofer. I'm looking to get a small Class D Amp and need to feed it the audio source. Instead of tapping into the left and right speakers in the rear, my idea is to splice the existing subwoofer wire and solder on a component cable. I would run the appropriate gauge wire for the power and ground as well the remote wire from the head unit. I didn't like the idea of the LC2i adapters since it seems like they add a level of complexity for something that may not be an issue on these cars. Is this setup feasible? Does anyone know the Low Pass Filter cut off or the range that the factory amplifier works with on this subwoofer channel? I understand by doing this, the factory speaker would essentially be dead weight and I'm okay with that.
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You need a LOC to clean up the factory signal. Due to the nature of the 10 speaker system, there is a lot of bass roll off. Best way to add an aftermarket sub is to tap into a full range rear speaker, run it through an LOC, and then to your amp and sub.
 

integra15

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You almost certainly need an LC2i or something similar. I tried it (multiple different powered subwoofers) with just speaker level inputs and it was terrible waste of time and effort.

As far as the signal goes, you have 2 choices the rear sub or one of the Front speakers. The rear speakers are all sorts of filtered and are not suitable for anything.

The rear sub has an extremely sharp cutoff and the frond have more of a gradual cut on the lower end. I chose to use the front because I did not want to lose the upper bass this is not present in the rear sub level. Plus you can add lower end bass back with the adjustments most powered subs and amps have.

Someone on hear measured and posted very detailed frequency response graphs of all the channels if you are curious to see what it looks like.
 
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kobaltz

kobaltz

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You almost certainly need an LC2i or something similar. I tried it (multiple different powered subwoofers) with just speaker level inputs and it was terrible waste of time and effort.

As far as the signal goes, you have 2 choices the rear sub or one of the Front speakers. The rear speakers are all sorts of filtered and are not suitable for anything.

The rear sub has an extremely sharp cutoff and the frond have more of a gradual cut on the lower end. I chose to use the front because I did not want to lose the upper bass this is not present in the rear sub level. Plus you can add lower end bass back with the adjustments most powered subs and amps have.

Someone on hear measured and posted very detailed frequency response graphs of all the channels if you are curious to see what it looks like.
Thanks for the information. So it sounds like the best option for a full range would be to tap into the FL/FR channels after the amp and send that into the LC2i and run the RCA cables down to the aftermarket amplifier.
 

jakabony

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You almost certainly need an LC2i or something similar. I tried it (multiple different powered subwoofers) with just speaker level inputs and it was terrible waste of time and effort.

As far as the signal goes, you have 2 choices the rear sub or one of the Front speakers. The rear speakers are all sorts of filtered and are not suitable for anything.

The rear sub has an extremely sharp cutoff and the frond have more of a gradual cut on the lower end. I chose to use the front because I did not want to lose the upper bass this is not present in the rear sub level. Plus you can add lower end bass back with the adjustments most powered subs and amps have.

Someone on hear measured and posted very detailed frequency response graphs of all the channels if you are curious to see what it looks like.
I tapped into the left rear speaker, and the only issue I have noticed is that the sub has a delayed start on a song. For example, some songs will start, where there should be low frequency, and a few seconds later the sub will respond. Not sure if this is what you are referring to or not. Either way, it isn't super noticeable to me. Also much easier to tap into the rear speakers for signal.
 


integra15

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Yes unfortunately gone are the days of getting a full signal from any of the channels at a speaker level input. But the closest are the front right or left (midrange). You can see some of the response curves in this thread

https://www.civicx.com/threads/audiophiles-touring-factory-eq-curve-doesnt-change-with-volume.6814/

I should add that if you do intend to add a powered subwoofer, it might be best to try both the front and the sub to see which you prefer. I spent a day listening to each setup and ultimately decided to use the front signal but it might be up to my music tastes.
 

jakabony

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Yes unfortunately gone are the days of getting a full signal from any of the channels at a speaker level input. But the closest are the front right or left (midrange). You can see some of the response curves in this thread

https://www.civicx.com/threads/audiophiles-touring-factory-eq-curve-doesnt-change-with-volume.6814/

I should add that if you do intend to add a powered subwoofer, it might be best to try both the front and the sub to see which you prefer. I spent a day listening to each setup and ultimately decided to use the front signal but it might be up to my music tastes.
I tried the sub and left rear signals, and went with the left rear. The sub signal just sounded super weird.
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