Amp for 15" Vibe sub

[simonlo]

Hi guys,

Never installed a sub before so need a bit of advice. First of all I need advice on what amp I should get for the sub:

Don't know exactly which one it is as I got it from a friend but theres a bit of writing on the speaker: Vibe 15" Pulse Alloy 3 Series, Butyl Surround.

Head unit is a P77MP Pioneer and I've got stock speakers (Fab vrs).

My friend said that the sub is 700 watts. I want to provide it with clean power but wont want to overpower the speakers so probably wont need something quite so powerful yet in terms of amp. However, obviously I dont want to underpower and therefore potentially damage the sub either.

Thanks in advance!

[bengie]

is that 700W rms or peak??

you really need to know the model number of the speaker to know what it needs to run it

and you can't really over power a speaker in terms like you describe. a 1000w amplifier doesn't kick out 1000w constantly but is in fact capable of putting out 1000w. you are more likely to do damage by under powering a speaker than over powering. if you run a 400W speaker from a 200W amp and run it loud then you will burn out the speaker long before the amp. more is better

what you need to be careful of is not driving a speaker too hard, its a difficult thing to understand at times but basically you want to match them if you don't plan on going further in the future or get bigger and turn the gain down if you want to be able to get bigger in the future

[simonlo]

I was hoping someone here would know the model number

I'll ask him about RMS or peak power. And I think I'll match the amp with the sub as I wont be upgrading in the near future. Thanks!

[bengie]

just take it out, it should be printed on the back of the magnet

[simonlo]

just take it out, it should be printed on the back of the magnet

Am I just being stupid.. the box has all the carpet covering so is there still an easy way to take it out? Can I not find out what sub it is from the info on the front of the speaker?

Edit: He cant remember whether its RMS or peak and he used to power it from a 300watt JBL amp.. might be a cause for concern? How will I know whether its blown or not?

[bengie]

the screws on the front of the speaker itself are what you undo to remove the speaker. unless it has a model number on the front then sadly your best bet is to remove it so you know exactly what it is, then google it for specs

[Mil]

is that 700W rms or peak??

you really need to know the model number of the speaker to know what it needs to run it

It's a 15" sub...it better be putting out that figure RMS 4 ohms of course.

[jjj84]

Max power (rms) is based on how much thermal energy the sub can evaporate so that it doesnt get too hot and break.

This sub has sensitivity probably around 1 W/1m 90dB

This means that with 1W of power this sub will be giving 90dB

2W 93dB

4W 96db

...

512W 114dB

3dB difference means that the noise has doubled..

I believe that normally you will be listening somewhere around 80-100dB and this means that an amplifier that can give 10W of rms is enough for you So i would say that amplifier with 100W RMS is enough with you.

Let`s still remember that its the lack of power that breaks the speakers.. when you are using all the power that the amp can deliver it usually means that the signal is starting to "break" and this "breaking" of the signal is the thing that is harmful..

Conclusion: you cannot have too much power, but there is no point of having it too much because you wont ever be using it so much.

[bengie]

thats the detailed version of what i said isn't it

but i'd say 100W RMS is way short of the required power level

[simonlo]

Thanks guys, I'm gonna take it apart and have a look soon. Will be back once I find out the model number!

[bengie]

It's a 15" sub...it better be putting out that figure RMS 4 ohms of course.

why??

the 12" subs in my car are 300W RMS (900W peak) and they thump very nicely and go pretty deep, but then i do have 4 of them

[walkie]

Not one for plugging, but I have a Alpine MRD-605 for sale if your interested?

Check my sig

[vindaloo]

Look for a dedicated subwoofer amplifier. Keyword to look for is "class D" (D for Digital). Digital amps. are far more efficient than normal class AB traditional jobbies.

Sub. is likely to be 4 ohms impedance, look for an amp that'll give around 500 watts peak into 4 ohms.

Have a look here.....

http://www.caraudiodirect.co.uk/product_info.php?products_id=2395&cadid=89cd0e8bf8de3e81576b33f7e32faf64

The amp. in question isn't a recommendation, just the one I was looking at.

You'll also need an amp. installation kit - the same site has options for those too.

J.

[bengie]

looking around they are about 700 - 900w peak so buying a 500w peak amp is the wrong thing to do, buy an amp the same power or bigger.

[simonlo]

Hi guys,

Looks like you're right bengie, opened her up and its a PT-150 900W @ 4 Ohms!! So I'm looking at a pretty expensive amp right?

Might think about giving it back to my mate and buying a smaller 10/12inch.. its taking up a lot of boot space at the moment!

So, bearing in mind that I ideally dont want to spend more than £200 in total would it be better to stick with this sub and buy an amp or get £80 back for it then I'd have £280 to spend on a smaller sub plus amp?

I like the sound from the speakers at the moment but I could do with a touch more bass (obviously!) but I'm not sure I need a 15inch beast! Wondering what peoples opinions were on 10/12 inch ones? Listen to most types of music but mainly RnB, Soul, slow jams etc

[bengie]

the following would be nicely suited to that sub

amp 1

amp2(walkie's selling one )