weak amp + good sub or vice versa?

[31337hxr 10+ year member]

I read somewhere its really bad to have weak subs and a strong amp. Thus, this could blow up your subs.

Is this true? So what about having Strong Subs and weak amps.

What does that do?

Is there anyway, i can learn the math of the watt conversion so I know how to distribute the powers and make sure its right?

i dunno jack squat about car audio so I'm a n00bie.

anyways, I plan to get two 15" Fusion Jonah FJ1511 subs with a Rockford Fosgate 1000 watt amp or the 600 watt amp.

I don't know which one is best for it.

thanks!

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[joegee87 10+ year member]

There is no truth to that theory according to me! It all depends on what you want. Do you want to bump? Do you want sound quality? Don't let anyone talk you into changing your system becuase they don't think it sounds good, its all in your preference!

 

[Registered 10+ year member]

Alright.

First off your theory is generally correct. You get a powerful amp on crappy speakers, you'll blow em. The inverse is also correct. If you have a weak amp and powerful speakers, you won't get near the bass if you had a powerful amp that the speakers need.

Secondly, I'd urge you to rethink two 15s. Unless you plan to rattle yourself apart, 15s aren't normally the way to go. You can get better sound quality from a quicker 12 compared to the sluggish 15. Even ONE 12 is enough to get good sound.

Last, Watts. There's no real conversion needed. You'll normally see "things" rated in RMS. This is the basic wattage your speaker can handle at any time, and it is also used to rate how many watts an amp can push. This is NOT the maximum wattage. This is just what the speaker/amp normally runs at (or should run at).

Pretty simple really. Say you have a 500RMS speaker. You'd look around for an amp that you like and can push 500RMS at the Ohm load your speaker requires. I'd probably advise going UNDER the rating to avoid overheating and breaking your equipment (if you can't afford the more powerful equipment).

Also, look into your local professional audio stores. Find a place that'll help you install your equipment. Unless you're an expert at car audio installs, I'd have them do it. This is to insure the best performance out of your system.

Reader's Digest Version:

1. Powerful Amp-Weak Speakers = Sound of you buying new speakers

2. Weak Amp-Powerful Speakers = Losing on a lot of potential sound

3. Rethink your system! Two 15s is a bit overkill for a first system. ONE 12 in a quality box with a quality amp will impress the hell out of you.

4. Explained Watts

5. Professional installs!

Hope it helps.

 

[31337hxr 10+ year member]

Hey thanks for replying...

okay so lets take this subwoofer for example:

Fusion fjl-1211 Jonah Lomu Woofer

-Power Handling 1300 Watts

-Voice Coil 3" Black Alloy SVCImpedence (per coil) 4 Ohms

and this amp:

Rockford Fosgate BD1500

1500 watts x 1 at 2 ohms

okay....assuming I will have two of these 12" Fusion's.....my friend told me I shoudl wire them in parallel.

okay so lets take this step by step and break it down:

the subs have 1300watts power handling? is that RMS or max watt?

so 1300 watts @ 4 ohms and the amp is 1500 watts at 2 Ohms.

so amp 1500 watts / 2 = 750 watts for each subwoofer.

so 750 watts @ 2ohms for the 1300watt 4ohm subs?

what does "ohm" mean or do?

is this setup bad or no?

thanks!

 

[Unregistered]

The 1300 watts power handling is most likely the peak power.

If you amp is pushing 750 rms watts through your subs thats probably over the subs rms. I have 2 12" Infinity Reference subs and their rms is 300 and the peak is 1200, so my guess would be 750 is going to be over the limit. I am pushing my subs at around 280 watts each sub and it is enough to rattle windows when you pull up to somones house. Another thing you need to consider is how good you head unit is. I have a Pioneer deh-p6300 (love it by the way) and you turn it up to about half as much as it will go and its a lot of bass. One other thing I would also recommend is saving a little money for some quality speakers and a littler amp to push them because a head unit just doesn't do it. I can barley hear the words over bass because I don't have front speakers, although I do have tweeters.

I hope I helped you.

You can always buy an amp that pushes more than your subs hold just turn it down some, and just play around with the settings on you head unit and amp when you get all you system together.

 

[mecpmaster]

ahhh you all forget.......tuning is very important too.

you dont have to max out those gains in order to be loud and sound good.

if you build the right enclosure, and tune your amp correctly and do not abuse it then your subs will play fine on that amp.

but if you are off on any one of these expect to smell some toasty coils soon!!

you could spend less on the amp and get a little better woofers

build a ported or single reflex bandpass enclosure that will rock with less power and have at least 6db or more output, but those boxes can be difficult to build correctly for a novice.

other wise do sealed box with the 2 12's and the rockford big mama and tune it right.

laterz

the master

 

[sk8board4life86 10+ year member]

first of all get what u want. get the fusion. i've heard it personally and 2 12's put a crack in the front wind shield of a car parked next to it.