audio question

[CMF_Pierce]

Guys, I have a 350 watt peak 2channel amp (150 watt avg output, at 1 channel @ 4ohm) that I'd like to hook up to a jvc drvn 12" subwoofer with 1200 watt peak (250 watt avg output).

Obviously low pass filter and wired properly, but will the amp burn out/ not give out sufficient power for the sub?

any help appreciated

 

[CMF_azman89]

Volume output will depend entirely on the sub and the sensitivity of it.
An extra 100 watts would be noticeable but not by much in most cases.
So long as the sub also has an impedance of 4ohms then it will be fine. But you may find that you want to crank it to get that extra bit of bass. You have to watch yourself. The amp and sub will be fine, but neither will last long if you crank up the bass and start clipping the signal, which you may not even notice.

I have a 10" 300wrms sub in my micra on a 300wrms amp, and threw in 2 cheaper 12" subs rated at 150rms each for fun one day and the 10" was louder, lower and smoother.

 

[CMF_RTK]

Subs are too much extra weight! Hahah

 

[CMF_Pierce]

thanks azman, RTK, the cars gonna be decent fast like i've previously stated in a couple threads, I'm aiming at around 110kw at wheels, and so far it seems the only thing stopping me from completing the goal is that work keeps on getting in the way. But I digress...

azman,

the sub is also 4ohms. Honestly my style of music is punk, screamo, metal, etc... more on the tweet side of things ;P
I just figured I'd take the plunge and stop using rear 6x9s for wubwubwub. So now my next question is this:

Will I run into any soundwave trouble having a sub in the back middle (run on low pass filter), with a 6x9 setup on either side of it (running high pass filter) and front door speakers?

The sub and rear 6x9s will all be facing the front of the car.

Thanks again

 

[CMF_azman89]

Could you elaborate please?
Sub and 6x9's in the same box? Or all in the parcel shelf?
I shall cater the answer for both anyway lol

All in the parcel shelf:
Shouldn't have a problem, providing the parcel shelf is strong enough to support it all and the sub is a "free air" type.

All in a box:
If the sub does not have it's own chamber it will push and pull the 6x9's a fair bit and destroy them quite quickly. The sub must have it's own chamber, divided from regular coax etc speakers. They simply move too much air to be in the same chamber as speakers.

However, just touching on the parcel shelf idea again, there is much more airflow in the boot and it's not a sealed chamber, so a "free air" sub will perform fine there and will not rip the 6x9's apart, as the volume of air in the boot is free to move about the rest of the cab.

Side note for RTK
I've never been too worried about weight in the micra, because it does well as a work commuter even with a little 10" sub in a small custom enclosure i built. I try not to run the car on the limiter in the twisties because the motor has never been in great nick. And i recently purchased a twin turbo beast for to satisfy my need for speed anyway
Sadly, i may be giving up the micra soon, when i've sorted out a few things on the new car. Car will be sold with another motor though and PLENTY of spare parts. I just don't have time for the little micra any more

 

[CMF_Pierce]

Azman,

Thanks for the speedy reply, in regard to the setup, my bad for not elaborating.

I have a 3 door slx, with rear seats removed and floor boards installed on top of sound dampening underlay, which is on top of a dynomat setup.

The subwoofer is in its own enclosed (non-ported) box which meets the cubic space requirements of the sub woofer itself, and the 6x9s are each in there own ported box (read aerpro 6x9 ported box).

in the back will look like this top down view:

Rear Right 6x9 -- SUBWOOFER -- Rear Left 6x9

(space from hatch to front seats)

SEAT Driver ------------------ Seat passenger

 

[CMF_azman89]

No problem mate
In that case, you will have absolutely no problem whatsoever.
It sounds like you've put some thought into this, good job.

Have fun with the installation

 

[CMF_RTK]

If you have 6x9 and woofer that's a bit much I'd go 6/6.5 with splits for clear sound then just have the woofer for bass

 

[CMF_Pierce]

It was desired RTK but wasn't in the budget at the time. I even made my own door cards with the spacers for 6.5" splits w/ tweeter but ended up simply buying soundstream coax 6.5" speakers for 50% off price. So I made new single speaker spacers for the door cards.

Gonna fibreglass the door cards tonight :-D

 

[CMF_RTK]

Nice, I am redoing all my door cards in Fibreglass maybe haha

 

[CMF_azman89]

Keen to see pics of these projects guys!

 

[CMF_RTK]

azman89 WROTE:

"Keen to see pics of these projects guys!

Hahah CBF! And plus camera, Fibreglass resin? Kinda messy

 

[CMF_Pierce]

Well i'll post pics of everything tonight but after that there won't be any updates for about 8 months. Im going to be busy enforcing the coalition against terrorism. (read: living in a bloody desert for 8 months)

On the plus side when I return I'll have too much money to throw at the micra haha

 

[CMF_RTK]

Pierce WROTE:
enforcing the coalition against terrorism. (read: living in a bloody desert for 8 months)

Defence Force??