Question with adding a subwoofer

[mechaghost]

Originally Posted by Shizuma

While looking around today I noticed under the trunk liner up near the drivers side rear seat there a metal box with cables in it, I wonder if that could be the factory amp, I hadn't pulled apart the trim panels though to see if the wires went to the speakers or not, does anyone know if that is the amp?

The oem brz subs are going to be on the driver side of the trunk

[eriktherod]

I thought I saw an extra wire coming from the battery terminal but I didn't really think to look where it went to (or what gauge it was). Then again, my FR-S came with the Bespoke "Premium" audio package.

[DSPographer]

The BRZ head unit is the same as the one in the 2012 Impreza. So, this thread about upgrading the Impreza audio may have some info of use to you:
http://forums.nasioc.com/forums/show....php?t=2298834

[nashsnazzy]

Ill be watching this thread with interest. I have some ED 6" subs that have been sitting in my garage unused for years. I would like to use those in the FR-S.

[FTEIGHTSIX]

Can anyone explain or provide a wiring diagram for the factory amp?

Im also trying to figure out where to tap into the system with a line out converter.

It would make sense to tap it there since it would save time,
avoid removing the center console & head unit,
and keep all my audio electronics tucked away in the trunk.

[xcelir8brz]

I have a Limited BRZ. Ended up running everything from the head unit and power cable from the battery. The rear amplifier in the trunk is used to power the back speakers. You could tap off of that, but for me, it was easier to do it off the back of the head unit. Take a look at my Public Profile, navigate to my web page, and look at the pix.

[fmsida]

How did you run the power cable? Did you drill the firewall or did you use an existing opening? I am assuming that you ran the remote-on using a pin off the HU??? Thanks.

[xcelir8brz]

Originally Posted by fmsida

How did you run the power cable? Did you drill the firewall or did you use an existing opening? I am assuming that you ran the remote-on using a pin off the HU??? Thanks.

I ran the power cable on the passenger side through the stock grommet to the passenger foot well from the engine compartment behind the battery.

Here is the head unit pin outs:

10-pin power/speaker harness
1 2 - - 3 4
5 6 7 8 9 10
(orientation: viewing pins on car's factory plug, wires pointed away from you)

Code:
1 RF+ (SUBWOOFER)
2 LF+
3 +12V Accessory (AMPLIFIER)
4 +12V Battery/Constant
5 RF- (SUBWOOFER)
6 LF-
7 Ground
8 Power Antenna (provides power to Subaru's antenna booster amp)
9 [NC] {amp remote turn-on signal on Toyota HUs, not Subaru}
10 Illumination+


6-pin power/speaker harness
1 - - 2
3 4 5 6
(orientation: viewing pins on car's factory plug, wires pointed away from you)

Code:
1 RR+
2 LR+
3 RR-
4 [NC]
5 Dimmer (Illumination-)
6 LR-


28-pin SWC/aux/mic harness
1 .. 14
15 .. 28
(orientation: viewing pins on car's factory plug, wires pointed away from you)

Code:
1 [NC]
2 Reverse Gear
3 Illumination Dimmer Cancel (Bright mode)
4 Mic ? (separate, possibly ground)
5 Mic ? (twisted w/ 19)
6 Ground (not connected to mic)
7-14 [NC]
15 [NC]
16 [NC]
17 VSS
18 [NC]
19 Mic ? (twisted w/ 5)
20 [NC]
21 SWC Audio (Seek, Volume)
22 SWC Mode + Phone
23 SWC Common
24 [NC]
25 Aux enable
26 Aux audio Right
27 Aux audio shield/ground
28 Aux audio Left


16-pin rear camera socket
1 ... 8
9 ... 16
(orientation: viewing pins on car's factory plug, wires pointed away from you)

Code:
4 ?
5 ?
6 Parking brake (CUT AND PUT RADIO SIDE ON GROUND TO 28 PIN HARNESS GROUND)
7 Camera +6V supply (HU sends power to OEM Camera)
8 Camera Video In
15 Camera Detect (connect this to chassis ground)
16 Shield/ground

[FTEIGHTSIX]

Just curious, what effect does cutting the parking brake wire and grounding it actually do?

Is that more for the GPS?

[xcelir8brz]

Originally Posted by FTEIGHTSIX

Just curious, what effect does cutting the parking brake wire and grounding it actually do?

Is that more for the GPS?

It bypasses the safeguards put in place so that as you drive, you can stream/watch movies via usb, etc.

[Spaceywilly]

I am going to try to use the stock amp location in the trunk and replace it with a 4 channel amp. I'd like to use those subwoofer outputs for the signal instead of using the front L/R signal that is already there in the trunk.

I took a look at the amp in the trunk and I don't think the power going to that amp is going to cut it. It was a very thin gauge wire and just run off a 15A fuse, so I think I'd be blowing that fuse even with my 200W amp. The good news is the L/R signal coming from the radio is there, and the wiring to the front door speakers is there, so I should be able to tap into that to wire in a 4 channel amp.

wiring diagram


location of amp (power connector is on the right)


closeup of signal connnector


The wires going into this connector are:
(1 is at the bottom left of the connector in the photo, 10 is the top right)
1 - Pink (looks orange?) - Left speaker +
2 - Blue - Right speaker +
3 - Light Green - Left signal +
4 - White - Right signal +
5 - Violet - Left speaker -
6 - Red - Right speaker -
8 - Green - remote signal
9 - Yellow - Left Signal -
10 - Sky Blue - Right signal -

[jpit]

spaceywilly, Thank you - this is very helpful. Do they use any bandwidth filters on the signals going to the woofer or tweeters?

[Spaceywilly]

Originally Posted by jpit

spaceywilly, Thank you - this is very helpful. Do they use any bandwidth filters on the signals going to the woofer or tweeters?

To verify that that amp is used to power the front door speakers I got in the car and turned on the radio with that amp unplugged. Only the dash and rear speakers were going and there was definitely no bass going to those speakers, so it sounds like they are using high pass at least on those speakers. I am going to use another high pass for the front door speakers once I add the sub, and a low pass on the sub. I'm not sure if they are sending the full signal to the door speakers or cutting out the highs, but just from listening it sounds like they are getting the full signal.

[jpit]

Spaceywilly, one additional question. If you are going to install a bigger amp should you take the r/l signal before it gets to the oem amp or do you have to connect it to the r/l speaker leads after oem amplification?