500 RMS sub suggested to be powered at 300 RMS? Mistake?

[shilent 10+ year member]

the hifonics will kill anything audiopipe has. soundstream rubicon series. is best budget sq I know of.

I'm also looking for an SQ amp for my sub. Are Hifonics good? The prices seem really good.

 

[ckunke002 10+ year member]

the hifonics will kill anything audiopipe has. soundstream rubicon series. is best budget sq I know of.

So you like the hifonics amp? I've never read anything bad about it until here. I'm looking into that soundstream amp now too. Do you know what the guy up there is talking about when he says that the box affects power? I'm not reading that anywhere else

 

[Bettr n' Revrse 5,000+ posts]

Box has everything to do with what a sub will hold power wize... And Im pretty sure you arent going to notice a ton of difference in SQ with the amps you are looking at... As I just said in another thread you will need to spend some cash if you want an "SQ" amp

 

[zako 10+ year member]

I've been researching and shopping subwoofers for the past week and this has really been throwing me off. I've always understood RMS ratings to be the amount of wattage that SHOULD be powered to the woofers (within 10% or so) for best sound quality and output.

That should not be a rule that's carved in stone. There is a lot of misconception about this. Sensitivity of your final setup is a lot more important (and that involves the box). Lets say you have two subwoofers rated for 250watts and 500watts RMS respectively, but they have exactly the same sensitivity in a sealed box. If you're happy with the output of the first subwoofer powered by a 250watt amplifier, then you can also safely run the "500 watt" subwoofer with your 250watt amplifier, and still enjoy the same level of output. For example, my Infinity Kappa subwoofer is rated for 350watts of power, and I am very happy with its output with "only" 300watts running to it. The Image Dynamics IDQ v3 subwoofer has power handling of something like 700watts, but sensitivity that's actually a little higher than the Kappa. This means that I can enjoy pretty much the same output or better if I connect the IDQv3 to my 300watt amplifier. A lot of people do not understand this, and insist on blindly buying the amplifier to match the RMS rating of the subwoofer, even if they don't need that kind of output.

Another thing about RMS wattage ratings of subwoofers is that they are NOT mechanical power handling rating. These are thermal ratings. If you model subwoofers with WinISD and take a careful look at excursion plots, you will see that a lot of subwoofers will handle more power excursion wise than their thermal rating suggests. At the same time there are subwoofers, that will not handle mechanically half of their rated RMS wattage. I prefer to model the mechanical excursion of the subwoofer with software, ignore the sub RMS rating, and instead conclude that subwoofers "upper limit" of power handling, is the wattage at which the cone excursion exceeds the subwoofer's one-way xmax at say 30Hz. I am not worried about exceeding my subwoofer's thermal rating this way, because after all, I play music and not RMS test tones at full tilt.

To make the matters more confusing, let's say you want to have 500watts RMS available to your subwoofer. Will 500watt amplifier be sufficient? Probably not. Amplifiers are usually rated with 14.4volt battery, but the voltage of your car's electrical system even with engine running, is probably lower than that. You would probably need an amplifier rated 25% higher than 500watts (at 14.4v) to get the 500watts in a typical car.

 

[zako 10+ year member]

If you are going with a sound quality sub put a better amp on them. Atleast one that will do rated before 10% THD

Doing rated at 10% THD is terrible. Most ratings are done at 1% THD. If your amplifier needs to reach 10% THD to do the rated power, then it certainly does not provide the rated at 1% THD.

 

[zako 10+ year member]

My budget is around 300 for an amp. I want good sq though.. What is your range when you're referring to cheap?

That's a fine budget for a subwoofer amplifier. I would have bought a Boston Acoustics GTA-1000m, even though I don't need 1000watts RMS power, and run it in 4 ohm mode (best efficiency, and still more power than my subwoofer needs). Seriously though, every well known major amplifier brand that does not cut curners should be fine. Alpine, JL Audio, JBL, Kenwood, Kicker, etc. Precision Power "Power Class" mono block amp seems interesting too (it has parametric bass boost, as opposed to fixed frequency bass boost on most other amplifiers).

 

[globalminds_ent 10+ year member]

go with a sq woofer heard a lot of good things about re *** being great for sq for a good and 800 watts rms for sq amp is going to be a tuff one for $300 if u really want sq focal is what u need the FP!.800 is $800 and puts out 800 watts so I say this go with the re *** subs and a good mb quart because it will be cheaper to get better subs than a good sq amp

 

[globalminds_ent 10+ year member]

That's a fine budget for a subwoofer amplifier. I would have bought a Boston Acoustics GTA-1000m, even though I don't need 1000watts RMS power, and run it in 4 ohm mode (best efficiency, and still more power than my subwoofer needs). Seriously though, every well known major amplifier brand that does not cut curners should be fine. Alpine, JL Audio, JBL, Kenwood, Kicker, etc. Precision Power "Power Class" mono block amp seems interesting too (it has parametric bass boost, as opposed to fixed frequency bass boost on most other amplifiers).

Boston acoustic very good sq too

 

[winkychevelle 10+ year member]

all things considering the hifonics should do fine. though id recommend uping your budget a little and getting a zxi60.4+1k as it is 370ish shipped at audiosavings.com . i have had this amp pushing my memphis mclass components in bi-amp mode and a memphis c3 at 2 ohm and it sounded fine. most of the install from the local shops didnt even sound as good. i have clamped this particular amp to make 720ish watss at 2ohm on 13.8v and i believe it could of made its rating of 750 at 2 had my cruze not been a panzy with the voltage control. its a big amp but it runs cool and is very flexible. lots of power on the sub channel and ample power on the 4 chaneel side.

just my .02