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HepaKing Alpine PXE-X121-12EV DSP Review

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I’m back on it this weekend, I’ve got the final mounting of everything in this sub trunk
I added a USB outlet for the LED lights behind the aluminum plate, A fuse block, ground lug and disconnect switch.
My next project is upgrading my brakes to performance Benbro, my calipers are painted green that I did in 2018, they’ve held up well but now I’m going red, and will probably get the car wrapped in red. That is why I’m starting to change the color scheme to more of a red on the plate. Everything bolts to the plate so that I can modify it later on. I’ll bring the cables underneath through the black trunk liner. Also, everything can be removed, and the amp mounted back where it came from if desired at some point.

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Still haven’t got it finished. a lot of cleaning with five years of dog dirt.

Finally figured out how to plug the harness to the front amp.

It appears the speaker underneath the passenger foot well does nothing.

Not sure what the speakers do in the upper pillar. Maybe they used for voice etc..

The Hepaking kit does not come with a tweeter for the dashboard. I am not quite sure why it might be difficult to plug the new one in.
You can see the wrench that comes with the kit to help you get to the speaker screws on the dash

Link to photo showing the audio connector
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about to have this thing finished. I had to move the controls to the console because the cables were not long enough without extension to go to the display. I do have the USB cable and the second roller for the subwoofer amplifier.View attachment 1026691
Still have to mount some trim and the second subwoofer
View attachment 1026690View attachment 1026693View attachment 1026694View attachment 1026700View attachment 1026701View attachment 1026702

thanks for the progress pics.

looking really good!
I put together a quick video showing some of the progress.
I’m getting a little vibration out of the subwoofer. I might try replacing the 3-D printed with the wooden one.
I also cannot figure out how to get the output out of the RCA connector to drive my second subwoofer amp
I can see where he set up the input for the RCA, but I don’t see the output anywhere
The sound is amazing compared to the OEM premium system, The sound insulation also works very well
And replacing the suspension also with an unplugged performance, luxury suspension, also updating the brakes to the OEM Red brakes for vanity reasons only

Speaker Output
CH1: Left Tweeter (also to the roof tweeter, you can disconnect the roof tweeter connection if needed
CH2: Right Tweeter (Same also to the roofer tweeter)
CH3: Left Min Range Speaker on the Dash
CH4: Right Min Range Speaker on the Dash
CH5: Left Mid Bass (Door Woofer)
CH6: Right Mid Bass (Door Woofer)
CH7: Left Rear Door and trunk
CH8: Right Rear Door and trunk
CH9: Center Mid Range Speaker on Dash
CH10: No speaker
CH11 - CH12: Subwoofer

I’ll replace this video with the final one once I get things figured out

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Looking great. Much of the fun of many hobbies is the research, planning, building, problem solving, and getting things to work well, and constantly better. Incredibly frustrating for my wife 😂
I do enjoy that part. Although I do enjoy using the finish product more, especially when it seems like the effort was worth it, like this sound. I’ve been living with the premium sound for five years, it was so disappointing. The difference is so significant. The Tesla subwoofer was developed for SpaceX as it was the lightest subwoofer I ever picked up. Great range not very good for sound.
It can create problems, it might’ve had something to do with my divorce, but now I can lay out suspension on my kitchen table without the lecture although it was very costly so I don’t recommend following my lead.
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I finally got it sorted out.
I added a relay, and connected to the switched accessory wire, To turn my second amplifier and LED lights off.
Well, doing the final connection, my wrench did shorted out for a split second, I then was getting a battery fault error. It took me a while to sort that out and reset it., I did not have to buy a new battery this time at least.
The smaller red wire here is where I tapped into it based on a video on the Internet. it is switched and turns off if the driver is not in the driver seat.
I will be replacing the video with a much better video showing all the software, set up
The sound is night and day. A total pain in the butt, but I am so glad I did it.
I just wish I would’ve done it years ago

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I like the seat pressure switch idea. Adds an extra layer of protection.
I could never get the auto sensing of the Alpine subwoofer amp to work. it would stay powered up when I had it directly powered from underneath the rear seat. Also, my LED lights would not turn off, and sometimes the stereo would continue to play once I’ve locked the car.
The Alpine DSP is powered directly as well as my trunk lift, so the kick sensor works. The DSP does turn on and off automatically very well.

This was the closest thing I could find an ACC input. Some of the newer cars have this “B” power on the cigarette lighter in the console. I took mine apart only the 2018’s did not have that.

I use the high to low signal converter, and tapped into the subwoofer 2 channel speaker output on the DSP for the subwoofer amplifier.
If I did it again, I would probably use channel 10, which is currently unused for the subwoofer amplifier. I do have the gain turned all the way down on the second amplifier because it does rattle the car a bit. Finally some bass