Help selecting 12” sub-woofer and 5 channel amp

[Anime]

Generally a 4 ohm setup is more efficient than a 2 ohm setup.

What that means is the amplifier converts more of the juice from the battery/alternator into the 200 watts needed to push the sub at 4 ohms and move air to make bass, and less into heat as waste energy.

This isn't always true, though. There are amps that are purpose-built for a 2 ohm, 1 ohm, even 0.5 ohm load that are most efficient at that load rather than 4 ohms.

But, as above, the general rule is, 4 ohms is the "sweet spot" of highest efficiency for most car audio amplifiers, for the most watts with the least heat.



The specs on the R600X5 are:

CEA-2006 Power Rating
50Wx4 + 200Wx1 @ 4Ω
≤1.0% THD+N

Efficiency (average):
Front/Rear: 64% @ 4-Ohm
Sub: 85% @ 4-Ohm


Given that the CEA-2006 specs are @ 4 ohms AND that the efficiency is rated @ 4 ohms, I would guess that the amp, like most, is most efficient at 4 ohms. If it had a higher efficiency at 2 ohms, surely they would proudly print that in the specs.

It looks like RF is pulling the industry BS tactic of using the "600W" designation in the advertising and model number even though that's only what the amp puts out at 2 ohms.


You can of course use a 2-ohm sub rated for 300W and it'll work fine, and might put out more bass if that's what you're after. If you just want decent bass, the 200W sub @ 4 ohms will give you that 85% efficiency, and the amp will be sucking 1/3 less juice to push the sub.

 

[DjDom]

Anime summed it up. Stick with the 4 ohm, makes your life easier since you've already picked out a 4 ohm sub.

 

[bronchole]

Amp, Sub and 6 channel RCA cable ordered! Looks like it won't be here until 4/20 which means it will have to wait until after my upcoming trip to be installed. Thanks for all the input guys.

 

[GRNMACHINE]

Great reviews on this amp and great price. Was checking out the owners manual, the amp has 3 sets of RCA inputs--any idea how to install it to aftermarket head unit that only has 2 sets of RCA outputs?

 

[bronchole]

Post a link to your head unit.

It sounds like your head unit doesn't have a dedicated sub output. Are you intending to run a sub woofer?

 

[MotorCityFats13]

cea-2006 compliance requires all measurements to be calculated at 14.4v @ 4 ohm.... most amps perform better when you drop the load others not so much... if you never plan on adding another 12 I would buy the 2 ohm because it gives you more over head when you tune it up.... the box also changes the power the sub can actually take... sealed vs ported... and air space at what port tune..... brands rate subs conservative to reduce warranty claims the good brands, taking it that you are not sending a clipped signal can take more power with no negative effects.... once you hit the point of no return it sucks.... but if you plan on doing 2 subs later on and the one sounds good you can buy another drop the load and the amp will power both just fine...

 

[bronchole]

I am only going to run the 1 sub.... ever! I have it in a sealed enclosure and inside the fenderwell. See this.

 

[driver460sz]

I just put in JL 6.5, 6.25 in the doors and tweeters, a 10w3 sub in a stealth box, Alpine DiD 7 inch radio/GPS and a 700xd/5 running the doors and sub. Sounds very nice and hits great for a single ten. The amp is running the doors around 1/3 gain the sub is at 2/5 gain.