How-To Guide: Model 3 SR+ aftermarket to enable speakers and subwoofer upgrade install

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LRonHoyabembe

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#22
Oh, ok . Thank you !
It would be interesting to see if this amp can be hooked up without the relay stuff though (if you don’t install a sub as well). It’s pretty low power; the fuse is only 15A. You could probably get away with connecting straight to 12V penthouse.

I forget, @PLUR did you hook up the alpine to the relay, or just straight 12V?
 

PLUR

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#23
It would be interesting to see if this amp can be hooked up without the relay stuff though (if you don’t install a sub as well). It’s pretty low power; the fuse is only 15A. You could probably get away with connecting straight to 12V penthouse.
I forget, @PLUR did you hook up the alpine to the relay, or just straight 12V?
From Ingineerix: "This video shows how to safely get a switched 12 volt line for powering up to 10 amps of accessories in you model 3. I tested this for 10A continuous load, and it "trips" at 15A, so as long as your wiring can handle up to a 15A fault current, no fuse is needed. "

For my setup: the VCLeft 12V is to power the LC7i+remote in signal. 12V Penthouse to power sub amp and alpine amp.
 

LRonHoyabembe

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#24
From Ingineerix: "This video shows how to safely get a switched 12 volt line for powering up to 10 amps of accessories in you model 3. I tested this for 10A continuous load, and it "trips" at 15A, so as long as your wiring can handle up to a 15A fault current, no fuse is needed. "

For my setup: the VCLeft 12V is to power the LC7i+remote in signal. 12V Penthouse to power sub amp and alpine amp.
Right, but is the alpine hooked up to the solid state relay like the sub amp? I'm wondering if someone could skip all the relay business if they don't want to add a sub.

Edit: sorry, looks like you skipped the relay altogether. Be sure to update us if you run into any issues!
 

PLUR

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#25
Right, but is the alpine hooked up to the solid state relay like the sub amp? I'm wondering if someone could skip all the relay business if they don't want to add a sub.

Edit: sorry, looks like you skipped the relay altogether. Be sure to update us if you run into any issues!
Yeah no relay... The accessory 12V power the LC7i "remote in", then LC7i "remote out" line powers the alpine "remote in", then the alpine "remote out" powers the subwoofer amp "remote in".

My guess and hope is that this setup will provide enough of the delay that the sub would powers last and so less chance of throwing the penthouse error. Will report if I get any error. :)
 

LRonHoyabembe

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#26
Yeah no relay... The accessory 12V power the LC7i "remote in", then LC7i "remote out" line powers the alpine "remote in", then the alpine "remote out" powers the subwoofer amp "remote in".

My guess and hope is that this setup will provide enough of the delay that the sub would powers last and so less chance of throwing the penthouse error. Will report if I get any error. :)
The error folks were getting for the penthouse 12v wasn't about the sub amplifier turning on, but rather, the sub amp being connected. Aftermarket amps have large capacitors that charge up before the amp is turned on. Typically, this happens the moment you connect the amp to your car's battery. Once it's connected, it's good for the foreseeable future because the battery & capacitors have distributed power to where it wants to go.

The Model 3 is different because, instead of a 12V battery, we're using the 12V DC-DC converter. This unit actually turns off during sleep, which means the sub amp's capacitors are drained to 0%. When the DC-DC turns back on during sleep (to charge the car's 12V battery, among other things), the sub amp's capacitors try to charge 100% immediately. This causes a huge current rush for like a half a second. This rush, which could be tens to a hundred amps depending on size of capacitors, causes the 12V to trip because it's just too much power all at once. Have you ever disconnected a 12V battery from an ICE car, and then when you reconnect it, you get a spark?

The relay+resistor circuit allows some voltage through when the car is off, but limits it greatly to prevent high amperage being pulled by the sub amp's capacitors. When the DC-DC turns off, the capacitors still drain to 0%, but when it turns back on, they charge up much slower; at a rate the penthouse 12V is happy with. Then once the car is actually "on", the relay is activated, which allows 100% of the power to be delivered to the amps, thus bypassing the resistor completely.

Whether or not you trip the 12V seems to be dependent on how large the capacitors are on your amp, and how lucky you are in general. Some people have been fine, others not so much. So YMMV.
 

LRonHoyabembe

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#27
@PLUR how did you tune your alpine 4ch? I'm not thrilled with how the 2ch summed input is balanced. Since input only comes from the rear door speakers, you only have 1 gain control for rear deck and front tweeters. I'm considering splitting the audio before it gets to the amp, setting it to 4ch mode, and adjusting each gain knob separately. I think my tweeters are just a bit too loud and it's drowning out the mids. Thoughts?
 

PLUR

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#28
@PLUR how did you tune your alpine 4ch? I'm not thrilled with how the 2ch summed input is balanced. Since input only comes from the rear door speakers, you only have 1 gain control for rear deck and front tweeters. I'm considering splitting the audio before it gets to the amp, setting it to 4ch mode, and adjusting each gain knob separately. I think my tweeters are just a bit too loud and it's drowning out the mids. Thoughts?
1st) Change your alpine jumper to 2ch input setting since you only using the rear speakers as signal (default jumper is 4ch, look on bullet #14 in manual).
2) Wiring from your rear door speakers should go to the RCA Input Jacks FRONT=Grey sleeve (leave the RCA input jack REAR=Violet sleeve alone, not attached to anything)
---This is assuming you don't use LC7i, if you use LC7i then only the 2ch (summed output) from LC7i go the alpine RCA Input Jacks FRONT=Grey sleeve---
3) For your output cables (alpine has 4 channels), use each channel for each speaker (front left + front right for your two tweeter, and rear left + rear right for your rear two shelf speakers respectively)
4) Now you can independently set the gain knobs on your alpine, "front gain" for tweeters and "rear gain" for the rear shelf 4"
 
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LRonHoyabembe

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#29
1st) Change your alpine jumper to 2ch input setting since you only using the rear speakers as signal (default jumper is 4ch, look on bullet #14 in manual).
2) Wiring from your rear door speakers should go to the RCA Input Jacks FRONT=Grey sleeve (leave the RCA input jack REAR=Violet sleeve alone, not attached to anything)
3) For your output cables (alpine has 4 channels), use each channel for each speaker (front left + front right for your two tweeter, and rear left + rear right for your rear two shelf speakers respectively)
4) Now you can independently set the gain knobs on your alpine, "front gain" for tweeters and "rear gain" for the rear shelf 4"
Huh. Are you sure this is correct? Maybe mine is different since I'm using direct high level speaker inputs v.s. RCA from something like your LC7i. For me, if I adjust the "rear input" gain, nothing changes because I have no rear input. The only input is the rear door speakers, which goes to front input on the alpine.

Since the knobs aren't "output gain", my front input gain knob controls both channels at once.
 

PLUR

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#30
Huh. Are you sure this is correct? Maybe mine is different since I'm using direct high level speaker inputs v.s. RCA from something like your LC7i. For me, if I adjust the "rear input" gain, nothing changes because I have no rear input. The only input is the rear door speakers, which goes to front input on the alpine.

Since the knobs aren't "output gain", my front input gain knob controls both channels at once.
If direct high level, Cut off the RCA jacks, then connect the correct corresponding speaker outputs from the head unit directly to these twisted pair wires.
Check your jumper setting for alpine, also check that each speaker you are powering from alpine is power from each line-output from alpine (do not group any of them together)

If you still getting issue and think it has to do with direct high level input, then yeah I see splitting the high level line-in from 2 to 4 wires might do the trick after changing jumper to 4ch.
if this doesn't work, you can try another method of buying a speaker signal converter high to low(RCA) and use my method again. Hope it helps
 

PLUR

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#32
Penthouse is the 12V+ power that sits under the right rear passenger seat as shown here.
In gas car, you connect the aftermarket amp to your car battery but with the Model 3, you connect to this area for power.

Side note: I updated my setup wiring for LC7i, the reason for this was that I was getting a small "thump" sound from subwoofer when I power on my car. With the new setup i updated in LC7i, the thump is gone. I still don't have any relay, and no error "cannot maintain vehicle power".
 
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#34
Do the rear door midrange speaker signals have enough high frequency content for the mirror tweeters? Wondering if it's better to take signals from the dash speakers instead? Then front/rear fade control still works.

Also, does it make sense to tap all signals from the ICE since they will be all in one location?

Thanks!

Oh crap... are you driving your tweeters from the rear door speaker audio?

Edit: just re-read. Yes you are. I feel like a dummy. I have front door woofer audio going to the tweeters. No wonder there’s no sound... should be an easy fix though.
 
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#36
I'm going to be attempting this this weekend. Just adding the LC7i and Alpine power pack to get the tweeters and rear deck working, but setting myself up for a potential subwoofer addition in the future. I'm not planning on adding the relay+resistor since I don't think OP did it (I'm essentially copying his build).

My question is: should I be adding the relay+resistor? And if I should, what is are the best options?
 

LRonHoyabembe

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#37
I'm going to be attempting this this weekend. Just adding the LC7i and Alpine power pack to get the tweeters and rear deck working, but setting myself up for a potential subwoofer addition in the future. I'm not planning on adding the relay+resistor since I don't think OP did it (I'm essentially copying his build).

My question is: should I be adding the relay+resistor? And if I should, what is are the best options?
I suggest reading this in full. His install is far more complicated than what we've been doing, but a lot of the same stuff applies. https://www.travisllado.com/2019/05/tesla-model-3-stereo-part-9-summary-and.html

Also, you don't need the LC7i if you're just doing the tweeters and rear deck. I have audio going straight to the alpine, then straight out to the tweeters and rear deck. Then I used an LC2i for my subwoofer. Slightly cheaper this way, but really down to preference.
 

Defjukie

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#38
I'm going to be attempting this this weekend. Just adding the LC7i and Alpine power pack to get the tweeters and rear deck working, but setting myself up for a potential subwoofer addition in the future. I'm not planning on adding the relay+resistor since I don't think OP did it (I'm essentially copying his build).

My question is: should I be adding the relay+resistor? And if I should, what is are the best options?
I would add the relay & resistor. I ran without it for months until a few weeks ago, after a software update. My audio went completely dead, and wouldn’t come back. Another software update briefly brought it back, but it went out again after a day or so. They added some sort of check in the firmware that was checking current/voltage from the penthouse, and it was causing the fuse to trip.

I added the relay and haven’t had an issue in a couple weeks.
 
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#39
I would add the relay & resistor. I ran without it for months until a few weeks ago, after a software update. My audio went completely dead, and wouldn’t come back. Another software update briefly brought it back, but it went out again after a day or so. They added some sort of check in the firmware that was checking current/voltage from the penthouse, and it was causing the fuse to trip.

I added the relay and haven’t had an issue in a couple weeks.
Did you use the solid state relay as well, or something like this?

I suggest reading this in full. His install is far more complicated than what we've been doing, but a lot of the same stuff applies. https://www.travisllado.com/2019/05/tesla-model-3-stereo-part-9-summary-and.html

Also, you don't need the LC7i if you're just doing the tweeters and rear deck. I have audio going straight to the alpine, then straight out to the tweeters and rear deck. Then I used an LC2i for my subwoofer. Slightly cheaper this way, but really down to preference.
Thanks! I didn't think of this I guess. I'll be ordering the LC2i instead of the 7i. I presume the same rear door speaker taps would go directly into the Alpine right? I also plan on adding bass blockers onto the tweeter outputs too.
 

Defjukie

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#40
Did you use the solid state relay as well, or something like this?



Thanks! I didn't think of this I guess. I'll be ordering the LC2i instead of the 7i. I presume the same rear door speaker taps would go directly into the Alpine right? I also plan on adding bass blockers onto the tweeter outputs too.
I used the product you linked