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Discussion Starter #1 (Edited)
Hi all, its been a while but I'm starting to build my car audio system.

The people on here have been great with providing me pro advise.

So i just ordered my Morel hybrid II's 6", and i need a good amp that has also good value to go with them.

I have a list of amp's that produce at least 140w rms x 2 at 4 ohm, and would like to get your thoughts, as there is good and bad reviews on all of them.

Rockford Fosgate Prime R300-4 - Review - Amazon.com: Rockford Fosgate Prime R300-4 300 Watt Multi Channel Amplifier: Electronics

JX360/4 - Review - Amazon.com: JX360/4 - JL Audio 4-Channel 360W Class A/B Amplifier: Car Electronics

ROCKFORD FOSGATE T400-4 - Can't Find anything bad about it, but is it worth the price?

ROCKFORD FOSGATE P400-4 - I guess i missed this one, but this seems to be perfect for my needs / value??

Only thing it says 8 - 18 awg, don't i need at least 4 awg?


Any other recommendations?

Which should i go for?

Also I'm going to bridge the 4 channels on these amps to get at least 140w rms at 4 ohm out of them, that all ok right? i won't have any problems?

also say after bridging them and i pick a model that does 200w rms x 2 at 4ohm, can i use the wasted rms to power my back pioneer 6x9's if I choose to install them in this car?

Thanks For Reading :)
 

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How about a real 2x150w into 4ohms, class A/B, new old stock for $100.

Aura RPM Stage 2 RPM2300 Mobile Amplifier 2 x 150W 269-189

Look at the ampguts on that thing. Well built, twin 40a fuses. Its a beast.

http://ampguts.com/forum/aura-46/aura-rpm-2300-stage-2-a-1987/

IMO, if you want 150rms x2, you should get an amp that is designed for that instead of bridging a 4 ch to get that power. Bridging makes the amp work harder and it runs closer to the design limits. That generally means that it doesn't have as much dynamic headroom.
 

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How about a real 2x150w into 4ohms, class A/B, new old stock for $100.

Aura RPM Stage 2 RPM2300 Mobile Amplifier 2 x 150W 269-189

Look at the ampguts on that thing. Well built, twin 40a fuses. Its a beast.

Aura RPM 2300 Stage 2 - AmpGuts.com

IMO, if you want 150rms x2, you should get an amp that is designed for that instead of bridging a 4 ch to get that power. Bridging makes the amp work harder and it runs closer to the design limits. That generally means that it doesn't have as much dynamic headroom.
Bill brings good point about Bridging...I try to NEVER bridge a amp unless absolutely necessary. The Aura amp is a good deal at 100$...
 

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That makes no sense when discussing best value. If you find a deal on a 4-channel just bridge it. Sure it works harder but no harder than running it at 2ohm stereo and all amp these days are designed to do both.

Dynamic headroom is not an issue if you have the right power and know the limits of the system.
 

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so it makes no sense to run a amp at 4ohms instead of 2 and prolong the life of the amplifier?...But just to clarify I didnt say that I never do bridge amps cause I do...I said I try not to...and lets face it this isnt a perfect world..sometimes you have to push limits...
 

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Not sure why 4-channel amps was even brought up though; no one mentioned he should buy one.:laugh:

If comparing a 2-channel vs a bridged 4-channel for the purpose of value and power, then it's likely to get more power out of the bridged amp. Assuming the heatsinks are designed properly I would take bridged for more power and more gain adjustability.
 

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Not sure why 4-channel amps was even brought up though; no one mentioned he should buy one.:laugh:

If comparing a 2-channel vs a bridged 4-channel for the purpose of value and power, then it's likely to get more power out of the bridged amp. Assuming the heatsinks are designed properly I would take bridged for more power and more gain adjustability.
Did you even read the original post? He listed four different 4-ch amps and was talking about bridging them to get 2x140wpc. I simply pointed out that for the same or less money, he could get an amp that was actually rated at 2x150w. If he wants a 4-ch amp for flexibility, then it is understandable, but it sounded to me like he wanted 2ch only.
 

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Yeah I did, but I completely forgot as I continued to read and post here. :blush: Sorry bill.

But, that still doesn't prove that a 4-channel would be a worse option.
 

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I dont think a 4 channel would be a bad option, it definately gives room for upgrades. (Ie (not knowing what kind of vehicle) he could run 4 channel on front and subs for now then later add a dedicated sub amp, using his 4 channel on front and rear at that time..) I think Either is a viable option not knowing all the specifics. If he just wants Front then a 2ch might suit his purpose perfectly, if he is going to add onto at a later date then a 4 channel would give him the jump on said process..


However I do think we are drifting horribly off topic..I think it behouve the OP for us to suggest amps and critic his stated choices more then to argue about other ideas...
 

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PPI 900.4

Just got mine installed last week. Super small, 4 channel 145w x 4 RMS @ 4 ohms (Pasmag tested and they do rated, search to find the link).

Bandpass crossovers up to 5khz.

$229
 

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Discussion Starter #12
wow didn't expect this many replays so quick, that Aura amp looks pretty good, I was all set on getting the RF punch, but it has no rca outs.

My plan is to see how i go with just the front speakers, then maybe later on add rear's however i will just use the pioneer 6x9 i have sitting here for 5 years now, i got no idea what the real rms is on these.

And i will most definitely add a alpine type x sub with a mono 1k amp.

If i get the 200 rms RF and i bridge it to x 2 @ 4ohm can i run the back speakers with 60w rms and leave the 140w rms for the fronts?

The most important thing to me atm is giving the fronts the rms they need at 4 ohm then doing the sub set-up a little later on

i guess i don't need output rca's from the RF if if the mono amp i get has rca outs do i? but thats a class d? so would it be better for the class ab to be sending the signal?

is there anyway i can save not getting a third amp for the rears? and still give the fronts the rms they need?

I'm trying to stick to a value - quality set-up

maybe i should just run the rears from the HU? i just want some rear fill really i think?
 

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ROCKFORD FOSGATE T400-4 - Can't Find anything bad about it, but is it worth the price?
I picked up a used one for $150 and it was great for what I needed it to do. 2 channels on the front stage at 4 ohms and the rears bridged at 4 ohms to a sub.

It was tested at 86 x 4 at 4 ohms and 287 x 2 bridged into 4 ohms I think.
 

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Discussion Starter #14
So i can do that? even with the punch? how does the set-up go? is there like a switch that changes the whole amp to 2 chan mode? and like a fader? so i just hook up everything like i would for 4 chan mode but it will separate the fronts and rears - 2 x2 - then use the fader? or is it more complicated then that?
 

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if you use the 400-4 and runs your mids and highs, and subs off of it...then no you will not have fade front and rear. you will basically be running fronts on right or left channel and rears on opposite channel then channel 3,4 will be bridged on a sub...
 

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Discussion Starter #16
I don't want to run my sub off it, just the fronts and rears on bridged 2 channel mode @ 4 ohm. will this allow me to control grains for both fronts and rears independently?
 

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The most important thing to me atm is giving the fronts the rms they need at 4 ohm then doing the sub set-up a little later on
...
is there anyway i can save not getting a third amp for the rears? and still give the fronts the rms they need?
...
I'm trying to stick to a value - quality set-up
...
maybe i should just run the rears from the HU? i just want some rear fill really i think?
The PRECISION POWER P900.4 that was suggested is a good value.
FREE SHIPPING $229.95 PRECISION POWER P900.4 4-Channel 900W Phantom Class D Amplifier

Rating @ 4 ohms : 145 Watts x 4 to run your front and rear speakers.

Then later the matching 1000 watt P1000.1 would be nice:
FREE SHIPPING $209.95 PRECISION POWER P1000.1 1-Channel 1000W Phantom Mono Class D Amplifier

Or if you want a REALY powerful two channel and plan to run the rears of the deck the P600.2 is rated at:
Rating @ 4 ohms : 190 Watts x 2 - $159.99
FREE SHIPPING $159.95 PRECISION POWER P600.2 2-Channel 600W Phantom Class D Amplifier
 

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The PRECISION POWER P900.4 that was suggested is a good value.
FREE SHIPPING $229.95 PRECISION POWER P900.4 4-Channel 900W Phantom Class D Amplifier

Rating @ 4 ohms : 145 Watts x 4 to run your front and rear speakers.

Then later the matching 1000 watt P1000.1 would be nice:
FREE SHIPPING $209.95 PRECISION POWER P1000.1 1-Channel 1000W Phantom Mono Class D Amplifier

Or if you want a REALY powerful two channel and plan to run the rears of the deck the P600.2 is rated at:
Rating @ 4 ohms : 190 Watts x 2 - $159.99
FREE SHIPPING $159.95 PRECISION POWER P600.2 2-Channel 600W Phantom Class D Amplifier
those are nice. here are some amps i found for a build i'm doing for a guy, the price is very nice, and the spec's as well, I'm not sure how they are yet but i have high hopes.

MB Quart Q4.150 (Q4150) Q-Series 4-Channel Car Amplifier



MB Quart Q1.1500D (Q11500D) 1500W RMS, Q-Series Monoblock Amp

 

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Yeah man! Those Quarts look good as well. Man these guys new to car audio have got it made. So many POWERFUL and efficient choices for cheap. That was not the case back in the day when I got into this hobby.
 

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To the original poster, there is no way to divvy up the wattage on an amp between the front and rear like you are talking.

If you have a 4 channel amp, you can use 2 channels on the front, two on 6x9s you mentioned. You will get the rated wattage to each of the 4 speakers and could control front/rear balance with a fader (assuming you ran 2 sets of RCAs).

If you have a 2-channel or bridge the 4 channel down to 2 channels, you can run fronts and rears, but there is no easy way to send 150w to the front and 50 to the rear. The wattage is split pretty much evenly between the fronts and rears (maybe a slight variation if the speakers have different impedance values).

Usually if someone wants rear fill (your 6x9), they power it with the head unit speaker outputs or have a separate small amp to power them. Most 6x9s are pretty efficient so they don't need much power.
 
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