Different Impedances and Gain Setting on Different Channels

[carboi91]

Hi, I want to get a 4-channel Kenwood Excelon X600F amplifier for my car. I'm planning on bridging the coils in an Alpine SWS-1043D dual coil sub rated at 300W and 4 OHM and bridging that on 2 channels of the amplifier giving the sub a 2 OHM impedance and 300W of power from the amp. On the third channel, I want to hook up two Infinity Reference 4032cf speakers rated at 70W and 2 OHM in series giving me an impedance of 4 OHM and 100W from the amp. On the third channel I want to have two Polk Audio db5251 components rated at 100W and 4 OHM wired in parallel giving me an impedance of 2 OHM and 150W from the amp. I made a quick diagram in MS Paint to help.

1. Can i keep the gain on the sub-woofer channel at 100%, one speaker channel 66%, and the other speaker channel at 70% so I can have the exact Wattage sent to each speaker, or do i have to find a middle-ground and not turn up the volume?

2. Can the amplifier handle having different impedances on different channels?

Any other tips or suggestions will help

Thank You,

Simon

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[FenixAudio 10+ year member]

Yes u can, each channel on a 4 ch is independent and can run at its minimal impedence and up.

If I were u I would get. 2 diff amps. But with the equip u have you will be limmited on the power u can put on the sub.

You should take the Inf. Ref and the Polks and run them in paralell on ch 1 and 2 running at 2 ohm. You can not tune ch 1 and 2 differently so it doesn't matter. So basically take your drivers speakers in paralell on ch 1 and the passanger on ch 2

Since your sub is dvc u will have to wire the sub in series on the sub for 8ohms and bridge the channels on 3 and 4 to run at 4 ohms. Do not paralell the coils onn the sub and bridge the amp it will not work the amp will over heat. Because u will be trying to pull 1ohm from the bridged channels.

 

[carboi91]

Thanks for the quick response. At least for now i want to run only one amp so save a some money but eventually I plan on getting a mono amp for the sub and using the 4-channel to power each speaker separate.

I like the idea of running the speakers in paralell on driver/passanger side, but the Polks are 4 OHM and the Infinity Refs are 2 OHM so wouldn't that give me 1.3 OHM total impedance?

I am also confused on wiring the sub-woofer. Because the amp is 2-ohm stable when bridged, why couldn't I wire the 4 OHM coils in parallel so the sub is 2 OHM total? Does bridging change the impedance of the amp or are there other factors I'm not taking into account?

Would it be better to get an 8 ohm dual coil sub and wire it in parallel so i have maximum power?

Thanks again

 

[Haunz 10+ year member]

I like the idea of running the speakers in paralell on driver/passanger side, but the Polks are 4 OHM and the Infinity Refs are 2 OHM so wouldn't that give me 1.3 OHM total impedance?

This is a good idea. Otherwise your stereo image will be front to back rather then left to right. If the amp is 2ohm stable when bridged then each individual channel is 1ohm stable... so it should handle the load without any problems...

 

[FenixAudio 10+ year member]

This is a good idea. Otherwise your stereo image will be front to back rather then left to right. If the amp is 2ohm stable when bridged then each individual channel is 1ohm stable... so it should handle the load without any problems...

This is not correct, his amp is 2 ohm stable per chhannel, once there bridged they willl be 1 ohm and that will not work.

As far as sub wiring if u parallel 2 4ohm vc's it will be 2 ohm at the sub. If u connect it to say ch 3 it will be fine but once u bridge 2 channels the amp will see one ohm and shut off.

As far as the speakers I would measure the actual coil of the ref speakers then if they are 2 ohm just wire them in series until u get a second amp.

 

[Haunz 10+ year member]

4-channel car amplifier * 100 watts RMS x 4 at 4 ohms (150 watts RMS x 4 at 2 ohms) * 300 watts RMS x 2 at 2 ohms (2-ohm stable in bridged mode) * MOSFET power supply *

The amp is advertised as being 2ohm stable when bridged.

 

[FenixAudio 10+ year member]

The amp is advertised as being 2ohm stable when bridged.

right, but once you bridge channels on a 2 ohm load it will see 1 ohm. if he connected a 4ohm dvc sub to 1 ch he would be fine but once you connect a 2 ohm load BRIDGED it goes to one ohm.

 

[helotaxi 5,000+ posts]

The amp is advertised as being 2ohm stable when bridged.

Not according to the owner's manual. It's only 4 ohm bridged, 2 ohm stereo stable.

 

[Phoenix Risen 10+ year member]

and just putting it out there but dont use the gain as a volume knob.

 

[FenixAudio 10+ year member]

Not according to the owner's manual. It's only 4 ohm bridged, 2 ohm stereo stable.

Well them that *****.so series the coils and bridge the channels and wahla 4 ohms...orr buy a 5 ch amp...lol