From what i gather the stock infinity amp is a six channel amp with two channel's going to each factory sub which have dual 2 ohm voice coils. This is 35wrms per channel or 70wrms per sub.

So lets say you have a 4 ohm 12" sub in a sealed box and you want to bridge all four channels into one. The problem you get that you split the resistance by each channel so it would become a 1 ohm sub which im not sure the stock amp can handle. But would an 8 ohm sub work? is it even safe to bridge four channels together?


I have also read that the stock amp is a four channel amp which means that the two voice coils of the sub would be in parallel for 1 ohm which would solve my issues. The sub i have has a selector switch for 2 and four ohms.

 

I think that won't work. The infinity amp produces 22 watt RMS per channel. 88 watt RMS is in my opinion not enough power to run a 12" sub. I would recommend an extra amp with high power inputs and integrated x-over for a 12" sub.

 

Its just temporary until i buy an amp.

 

Well, you can try it. To bridge 2 channels will work with small demandless 6.5" speaker chassis. Don't know what will happen if you bridge 4 channels. Don't know what will happen with an demanding 12" chassis. The amp wasn't made for this configuration. If you have bad luck the amp will be destroyed. So it's on your own risk.

 

Sorry, double post

 

Just a passing thought.. I was given an amplified bass tube (300 watts 10" sub dual voice coil). It came with about a 15 ft rca cable and a line leveler adapter which I used due to the rca plug conversion (tapped into the input side of the amp). I initially had the leveler dialed up full, due to the fact head unit output isn't exactly a "high level". I ended up with a buzzing from the stock speakers untill I dialed down the leveler. Anyone else ran across this scenario?

 

Sounds like a bad ground problem.

 

Well it's grounded back on the right rear lug where all the lights etc. are grounded..so doubtfull. Had it going for about a month now with no issues since I initially reduced the input feed.. but it was just odd it was like feedback into the main system as it was from the factory speakers..drawing off to much voltage/wattage maybe?

 

Do not connect any of the amplifier channels together. The chips do protect themselves from shorts across and shorts to battery and ground, but connected to each other is more risky. Each of the six speaker output chips are rated 45 Watts into 2 Ohms, at the chip. There are some losses in the amplifier assembly so real world power is a bit less. This is just shy of 10 VAC sine wave. Aftermarket speakers need more voltage. It is not worth the effort to connect an aftermarket speaker to the OEM amplifier.

 

What about wiring in two each 4 ohm single voice coil 6" subs rated at 100 watts RMS? How do I get the lowest possible ohm load to increase power but not risk damage to the stock amp?


Also, if the stock amp is replaced, how is the wheel speed sensor output to the body control module and controller antilock brake (pin 3 plug B) and the power top control module (pin 2 plug B)

PoweramplifierBconnectorpinouts.jpg

 

There are four channels for subwoofer. Each can drive 2 Ohms. The 4 Ohm speakers will draw half the current of the 2 Ohm coils, plus there are only two coils not four. The way to get the most out of this amplifier is four 2 Ohm coils. Aside from the original Harman speakers, you can use four single voice coil 2 Ohm speakers, or eight 4 Ohm speakers paralleled in pairs. Just find room for them. :-)

Pin 3 is from the wheel speed sensor to the amplifier. That connection makes the volume go up with vehicle speed. The power top connection changes the equalization in the amplifier to sound the same top up or top down. If you have a coupe it does nothing. Neither has to be connected to anything if you use a different amplifier, but it is important to insulate those wires, prevent them from connecting to anything if you use another amplifier. If you find an amplifier that can use these signals, let us know!

The pinout you posted has a few errors. None of the speaker connections are grounded. This is more accurate:

1 A Radio5
2 A Radio6
3 A Radio6
4 A GND
5 A RTO
6 A Radio4
7 A Radio3
8 A Radio5
9 A Radio4
10 A Radio3
11 A GND
12 A
1 B IGN-ON
2 B
3 B
4 B LTRR2+
5 B RTRR1+
6 B LTRR1+
7 B RTFT+
8 B LTFT+
9 B IGN-ON
10 B
11 B
12 B LTRR2-
13 B RTRR2-
14 B RTRR2+
15 B RTRR1-
16 B LTRR1-
17 B RTFT-
18 B LTFT-

 

excellent feedback and thank you for answering every question! Huge Help!