Amplifier specs requried for certain ohms?

[calais06]

Hey all,

I am thinking of buying a Focal 33KX (13") RMS 400W sub and enclosure to suit.
Link to sub specs

It is 4 ohms (2 x 2), does this affect which amplifier I will need to get to suit? Also will this need to be a class A/B amplifer?

Dont flame about not enough info, as i am not asking which amp to buy, just wanting to know about the ohms. Thanks

 

[sweefu]

You would want a decent quality amplifier to produce ~500wrms + at 1ohm or 4ohm, little more would be nice. Class A/B is a personal preference, most of the newer amps these days are class D circuitry (digital) some people believe the class a/b produce a nicer, more warm sound if that makes sense, compared to a cooler more clinical sound of a class D - though with sub bass, this is going to be eve less likely, if you consider the frequencies it will be playing.

 

[AmmoJammo]

sub can be wired at 1ohm, or 4ohm.

you'd be better off getting a monoblock that does ~400watts at 1ohm, or else wiring the sub at 4ohm, and bridging two channels of a 2 channel, or 4 channel amp.

If you're looking to amp the front speakers also, then I'd be getting a 4 channel to run front speakers and sub just to simplify things, and make the installation more compact.

 

[sweefu]

My bad!! I read it as 4ohm x2 -.- sorry!

 

[calais06]

I already have Focal 165KR splits up front running off a Focal FPP 4100 amp (front speakers amped only).
As a temporary measure, would the sub be able to run off the remaining 2 channels until I get a amp that is 400w @1ohm?
Link to Focal FPP4100 amp

In the description it says '3 channel use with bass adjustment' if you know what that means?

 

[AmmoJammo]

if you've already got the 4 channel amp installed, then just run the sub off the two rear channels bridged.

wire the sub at 4ohm, amp will do about 280watts, which should be fine for daily listening

 

[sweefu]

If you ever do feel it lacks volume or is not as dynamic as perhaps you wish it was, invest in a more powerful amplifier

 

[calais06]

The person pulled out that I was buying that sub off (basically half-price), so need to find another but I'm not wanting to pay $1029 retail price because that's ridiculous.
I'm after a SQ sub that can run off the 280watts at 4ohm, do you guys have any suggestions? I'm thinking maybe a Focal Polyglass series sub?
Up to around $500 for sub itself then I'll get a box to suit.
I've had a few loud subs with terrible sq, which is even more evident now that I have the nice splits up front.


Sent from my iPhone using Tapatalk

 

[calais06]

if you've already got the 4 channel amp installed, then just run the sub off the two rear channels bridged.

wire the sub at 4ohm, amp will do about 280watts, which should be fine for daily listening

Is the link below how I should wire the sub up to get 4ohms?
http://a248.e.akamai.net/pix.crutch...enter/car/subwoofer_wiring/1DVC_2-ohm_2ch.jpg

Never wired a sub before (only had them pre-wired or installed), so wanting to get it right!

Thanks guys.

 

[AmmoJammo]

Is the link below how I should wire the sub up to get 4ohms?
http://a248.e.akamai.net/pix.crutch...enter/car/subwoofer_wiring/1DVC_2-ohm_2ch.jpg

Never wired a sub before (only had them pre-wired or installed), so wanting to get it right!

Thanks guys.

Yes, thats correct, assuming you get a dual 2ohm sub.
You could also just get a single 4ohm sub if you don't plan to upgrade the amp in future.

I've had a few loud subs with terrible sq, which is even more evident now that I have the nice splits up front.

For the most part, any sub can be made to sound decent, just because its cheap, or can go loud, doesn't necessarily mean it has bad SQ.