Added a sub

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evan9r

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Has anyone found a way to make the sub louder at lower volumes? Around 15-6 or lower is typically where I listen to music with people in the car but at this level I cant hear sub bass at all. Is this the DSP at work?
 
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smurfslayer

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The way I understand it the factory sony and b&o amps and signal processing roll off bass in the upper ranges of volume. My completely unscientific observation running the kenwood 300w w/ 8” kicker at very close to max gain is that you can notice bass rolling off somewhere between 24-26 on the volume display. It may be rolling back sooner, but this is where I pick it up.

If that’s what you’re running already, have you messed with the crossover and gain settings on the amp?

I get a pretty linear increase in bass, but this can easily be washed out by white noise - wind noise from windows down, moon roof open etc.

I think if this setup isn’t enough for you then you may need to step things up a notch, maybe go to a 10” sub, pull the factory enclosure and add some wattage.
 

evan9r

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Whats your bass, mid, treble settings look like?

So I was near max gain on the sub with the LPF at 100hz or a little lower. My mid was about 3 clicks below middle, treble and bass were middle or slightly above. This setting is what gave me the best EQ with the RTA app on my phone, playing pink noise.

The sub is more than enough for what I want, in fact its too much bass at times. So what I did was turn the gain down slightly and kick the bass setting on the radio up a few notches and this helped.

Would running FORscan and sending a flat signal to the amp clear this up?
 
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smurfslayer

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The for scan doc has links to a guy who did this with a 2015 - would work on a ’17 Rap. it wasn’t a simple for scan change, they used a DSP of some sort.

On the surface, I would think updating for scan to send an unaltered signal shouldn’t need any other mods but I’ve not seen any reports of what happens when you start messing with the settings. The DSP isn’t cheap or easy to install so I’m inclined to believe it was implemented for good reason.

FWIW, I keep my bass/mid/treble close to stock. Maybe 1 over on the mid.
That’s about the closest I can come to picking up subtleties - rhythm guitar in ‘don’t fear the reaper’ or similar.
 

Wolfeman

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So this happened today - be careful when trying to melt the plastic as if you overheat it, it can potentially open up. I ended up cutting a large hole and plan on trying to figure out a way to close it up. It looks as if the screw holes will match up with the Kicker but I haven't screwed it in yet. Waiting to get the box buttoned up before trying anything with it. Just wanted to share my experience to save someone from doing the same thing. I'll try to update the thread when I figure out exactly how I'm going to fix this.

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smurfslayer

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This should be a pretty easy fix, just get a good epoxy, maybe pvc glue would work too. it doesn’t have to look pretty, nobody but you will know what it looks like.

Did you use a torch (like me) to achieve this reward? I only scored a participation trophy in this contest, only minor melting, easily fixed while still hot.

I was just behind the seat again this weekend finally replacing my temp connections. - I had a problem with the ground cable, it frayed and loosened in the crimp, causing me to have poor and eventually no sound through the sub. I traced it to voltage drop under load and found the bad ground. I realized 3 other connections could suffer the same fate so I got off my duff and ran 8 gauge from battery to sub box; put a fuse block at the battery and at the sub, with proper, permanent connections.

Anyway, it got me to thinking, I’ll bet there’s a way to shoehorn a 10” sub back there. hmm...
 

Wolfeman

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Since the first box that I worked on was an extra that I ordered on ebay and I was frustrated trying to find a source for polypropylene plastic to repair that box, I decided to just go for it on my stock box. Some things to note about this project that may help in the future.

The Kicker sub holes do in fact line up perfectly. Because of the increased depth of the mounting holes, you do need new screws. I used #12 x 1 inch sheet metal screws and they worked perfectly. I did have to grind the head down a little to get them to fit the holes in the subwoofer. Also, I choose hex head SLOTTED so that I would have something to get them screwed down because the subwoofer won't allow the nut driver to get down far enough.

Also, I found it better to heat the box with a heat gun from the outside and push from the inside. Takes longer but less likely to push through in my opinion.
 
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