Wattage Output from Bridged Channels

[WesSide 10+ year member]

Forgive me as I'm not fluent with this car audio shenanigans. Here's what I'm proposing to do with my sound system:

Install the Alpine PDX-4.100 4-Channel amplifier (seen here: Alpine PDX-4.100 4-Channel Power Density Digital Car Amplifier).

I'm going to purchase a pair of Type-R's that rate at 100w RMS @ 4ohms and place them in my front doors. I'll run both speakers to channels 1 and 2.

I'll bridge channels 3 and 4. This amp claims to push 200w RMS x 2 in bridged mode. If I have the bridged channel powering a sub, it will output 400w RMS @ 4ohms, correct?

With that, I'll install a Rockford P3L 12" sub. for the sake of longevity, it should be slightly underpowered, correct?

Thanks a bunch.

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[kr15 5,000+ posts]

no that 200x2 equates into 200 (ch 1 and 2 bridged) x 200 (ch 3 and 4 bridged)

 

[misfit138 5,000+ posts]

If you want to power an entire system with a 4 channel amplifier, take a look at this: Crescendo Audio :: Amplifers :: 1000C4 4 Channel Amplfier

That'll give you 125 watts rms x2 @ 4 ohms + 500 watts rms x1 @ 4 ohms.

 

[misfit138 5,000+ posts]

for the sake of longevity, it should be slightly underpowered, correct?

No

 

[WesSide 10+ year member]

no that 200x2 equates into 200 (ch 1 and 2 bridged) x 200 (ch 3 and 4 bridged)

Im not bridging channels 1 and 2. I'll run the front left door speaker into channel 1 @ 100w RMS, the front right door speaker into channel 2 at 100w RMS. I'll bridge channels 3 and 4 and together i should be able to output 400w RMS @ 4 ohms to a sub, yes?

 

[WesSide 10+ year member]

If you want to power an entire system with a 4 channel amplifier, take a look at this: Crescendo Audio :: Amplifers :: 1000C4 4 Channel Amplfier
That'll give you 125 watts rms x2 @ 4 ohms + 500 watts rms x1 @ 4 ohms.

That would be perfect however the highest-end alpine speakers I can find are the Type-R's, rated at 110w RMS. Would that work? Do you have any another suggestion?

Thanks a bunch. The Rockford subs I'm looking at are the Dual 12" P2L's... output 500w RMS @ 4 ohms. Perfect.

 

[misfit138 5,000+ posts]

Im not bridging channels 1 and 2. I'll run the front left door speaker into channel 1 @ 100w RMS, the front right door speaker into channel 2 at 100w RMS. I'll bridge channels 3 and 4 and together i should be able to output 400w RMS @ 4 ohms to a sub, yes?

No. The amp is rated for 200 watts rms x2 @ 4 ohms bridged. That means each of your front speakers will receive 100 watts and the bridged rear channels will produce 200 watts. That isn't nearly enough power for the subwoofer you're interested in purchasing.

Follow the advice in my earlier post. That Crescendo amp is cheaper and more powerful than the Alpine, and it has great build quality.

 

[kr15 5,000+ posts]

Im not bridging channels 1 and 2. I'll run the front left door speaker into channel 1 @ 100w RMS, the front right door speaker into channel 2 at 100w RMS. I'll bridge channels 3 and 4 and together i should be able to output 400w RMS @ 4 ohms to a sub, yes?

NO...slowly reread what I typed. You think because an amp is 200x2 in bridged mode that you get 400 into a 1 channel load? That first 200 comes from ch 1 and 2 which will be used by your highs. That second 200 comes from ch 3 and 4 which you will use for your sub. You will get 200rms total at 4ohm by bridging the rear channels

 

[misfit138 5,000+ posts]

That would be perfect however the highest-end alpine speakers I can find are the Type-R's, rated at 110w RMS. Would that work? Do you have any another suggestion?
Thanks a bunch. The Rockford subs I'm looking at are the Dual 12" P2L's... output 500w RMS @ 4 ohms. Perfect.

An extra 15 watts won't hurt hose Alpine speakers.

And yes, I have a lot of suggestions. I'd suggest components other than Alpine Type R's and I'd recommend an entirely different subwoofer as well.

 

[misfit138 5,000+ posts]

Here's my suggestion.

amp: Crescendo Audio :: Amplifers :: 1000C4 4 Channel Amplfier

components: CTX65CS - Image Dynamics 6.5" Component Speaker System

sub: IDQ10V3.D2 - Image Dynamics 10" IDQ Version 3 Subwoofer

wiring: http://www.knukonceptz.com/productDetail.cfm?prodID=KOL-AK4-4

deadener: http://www.secondskinaudio.com/vibration-mat/damplifier-pro.php

 

[WesSide 10+ year member]

I read an earlier thread, seen here: http://www.caraudio.com/forum/amplifiers/476372-bridging-my-jl-g4500.html

The kid bridged his channels and apparently quadrupled his output on the 3rd and 4th speakers. Maybe I read that wrong.

The Crescendo amplifier does the same thing. It's rated at 125w RMS x 4CH @ 4ohms. You said when bridging channels 3 and 4, you'll push 500w RMS for a sub.

 

[misfit138 5,000+ posts]

The Crescendo amplifier does the same thing. It's rated at 125w RMS x 4CH @ 4ohms. You said when bridging channels 3 and 4, you'll push 500w RMS for a sub.

Most amplifiers produce higher power at lower impedances. The Alpine PDX does not. It produces the same amount of power from 2 - 4 ohms. That Crescendo amplifier that I linked is made by a VERY highly regarded build house and it's backed by a rock solid warranty. It will do the power it claims if your electrical system can maintain a decent voltage.

If you're interested in powering a pair of components and a subwoofer with a single amplifier, the Crescendo will do that quite well.

 

[WesSide 10+ year member]

Here's my suggestion.
amp: Crescendo Audio :: Amplifers :: 1000C4 4 Channel Amplfier

components: CTX65CS - Image Dynamics 6.5" Component Speaker System

sub: IDQ10V3.D2 - Image Dynamics 10" IDQ Version 3 Subwoofer

wiring: Car Audio Wire

deadener: Damplifier Pro - Automotive Sound Deadener CLD Vibration damping mat - See what all the fuss is about

Excellent, thanks.

I like the Rockford sub because it comes in the enclosure and it's a ported sub. A friend of mine has dual P1's and he's had good luck with them.

I'll look over everything you have here. Sorry if this is a stupid question, but what is a deadener?

The only issue I'm having is that I have a mono amp that pushes 200w RMS and it dims my lights. Upon the thought of investing in a capacitor, I got laughed at. They told me to do the "big three". Even after watching the video, I'm not entirely sure what I would be doing (P.S. the alternator in a 2003 Jaguar X-Type is not conveniently accessible). Thanks again.

 

[misfit138 5,000+ posts]

Excellent, thanks.
I like the Rockford sub because it comes in the enclosure and it's a ported sub. A friend of mine has dual P1's and he's had good luck with them.

I'll look over everything you have here. Sorry if this is a stupid question, but what is a deadener?

The only issue I'm having is that I have a mono amp that pushes 200w RMS and it dims my lights. Upon the thought of investing in a capacitor, I got laughed at. They told me to do the "big three". Even after watching the video, I'm not entirely sure what I would be doing (P.S. the alternator in a 2003 Jaguar X-Type is not conveniently accessible). Thanks again.

I wouldn't buy a capacitor either. If you're having problems with maintaining voltage, and you obviously are, upgrading your "big 3" and installing a larger battery could very well solve the problem. There's no reason for your lights to dim when running such a small amount of power. If you aren't comfortable fiddling around under the hood of a mid grade luxury sedan, pay someone who is. That's the best advice I can give there.

Sound deadener is beneficial for a couple of reasons. It helps to reduce road noise, which probably isn't a huge deal in a Jaguar. It also adds some mass to larger metal panels which could vibrate otherwise. It also seals any holes in your doors, which will increase the overall performance of your speakers. Sound deadener, wiring and batteries are boring and lots of "noobs" hate buying them, but they're essential if you want a proper sound system in your vehicle...

 

[WesSide 10+ year member]

I wouldn't buy a capacitor either. If you're having problems with maintaining voltage, and you obviously are, upgrading your "big 3" and installing a larger battery could very well solve the problem. There's no reason for your lights to dim when running such a small amount of power. If you aren't comfortable fiddling around under the hood of a mid grade luxury sedan, pay someone who is. That's the best advice I can give there.
Sound deadener is beneficial for a couple of reasons. It helps to reduce road nois, which probably isn't a huge deal in a Jaguar. It also adds some mass to larger metal panels which could vibrate otherwise. It also seals any holes in your doors, which will increase the overall performance of your speakers. Sound deadener, wiring and batteries are boring and lots of "noobs" hate buying them, but they're essential if you want a proper sound system in your vehicle...

I asked the deadener question before I looked at the link. I have 18 sheets of 18x32 dynamat downstairs, got a sweet deal on eBay - brand new.

The light dimming is my biggest concern. Granted I had the gain turned up higher than it should have been, it's still not pushing very much.

I'll see what I can do about having the big three done, that's a necessity.

As far as a bigger battery, I'm not sure what I should be getting. It would help if I knew what kind of stock battery comes with my '03 Jag. I'll see if I can take a peek under the hood and find out.

Thanks a bunch for your help.