How to install sub amp on 2012 si?

[fergy016]

I just installed an audio control lc2i pre amp (before the factory amp) but not getting rca output.

It is designed for line level outputs (after factory amp). This is bad since the amp filters frequencies out.

The other option is to install wire to rca pigtails, but there are only 2 sub wires into the amp. A positive and negative.The pig tails will be looking for 2 negative wires and 2 positive wires.A left and right sub channel, we only have a single center channel.

The only option I see is wiring a wire to rca pigtail in parallel pre amp directly to amp. I have to see if that will work.

Any input always appreciated, just be kind, I am learning as I go.

 

[fergy016]

-Ordered Rockford Fosgate wire to RCA converter
-Ordered Female RCA to 2 Male RCA splitter (my amp prefers two inputs per the manual)

 

[fergy016]

Installed the wire to rca adapter at the plugs to the amp. It appears to not have enough voltage to trigger my SMD DD-1 or JL Audio 500/1 v1 amp. Verified amp is set on Input Voltage: Low = 200mV and 2V.
The factory sub is still functional, so I know there is output from the amp to sub.
I'm plugged into A5 and A17 on the 24 pin connector at the factory amp, but am not getting enough output voltage to trigger my amp.

I will have to ohm out my connections and see if they might not be crimped tight enough.

Next option:
1. Pull stereo and tap in further up.
2. Tap in after amp and use Audio Control LC2i
3. Have stereo shop do it.

 

[webby]

I wish I could be more helpful. It's not a topic I know much about. Hopefully someone will chime in

 

[fergy016]

Conclusion:
I tapped into the wires at the sub with the wire to rca connector. That resulted in too high of output for my amp to handle on high or low input.
Installed LC2i and that brought that down to an acceptable level. Now my amp is running optimally per the instruction manual.

In all the troubleshooting I did, the end result is me upgrading my metra loc to an LC2i. My goal was to bypass the factory amp, but that didn't work as I had expected.

The LC2i only works at post amp power. If your deck powers your speakers, it will work. If there is an amp like the premium stereo option that has a sub, the LC2i has to be installed after the sub.

 

[fergy016]

If you have a JL 500/1v2, here are the steps to tune the amp:

To start:
Turn bass knob all the way up
and flatten out deck eq
Check LOC output to verify it is Low = 200mV and 2V High = 800mV and 8V

Preamp Output Section:
-Output Mode: Amp Filter
-LP filter suggested: 12dB
Advanced Bass Control:
-Infrasonic Filter: On
-Q: .5 for broad freq amplification
-Center Freq: 50
-Boost (dB)/Gain: Knob takes place of this option
-Infrasonic Freq (Hz): 30
-Bass Eq: On
Amp LP Filter:
-Mode|Slope: 12dB (suggested when going through back seats)
-Filter Freq (Hz): 40
Amplifier Input Selections:
-Input Voltage: Low = 200mV and 2V High = 800mV and 8V
-Input Sens: All the way down. Bring up to achieve 31.6V while playing 50Hz test tone
-Signal Sensing: Off

Test sub via multimeter = Ohm 200. Should read 2 ohm
Input Voltage: Low = 200mV and 2V High = 800mV and 8V
Turn bass knob all the way up
Flatten out deck eq

Target AC Voltage at 2ohm= 31.6V @0 dB reference level at 50Hz

Need oscilloscope to test for clipping at Deck output/amp output to set gains correctly

Recommended equipment:
https://www.sonicelectronix.com/ite...Detector-Analyzer-by-Steve-Meade-Designs.html