Sub Question

[a.jenkin]

Evening all,

A while back i bought a sub and box from a member on here, the main reason i bought it was because it was in a box which fitted into the sidewall of the boot and to my suprise it also came with a 3000W pioneer sub.

It was to replace my 600W sub running from a pioneer 300w amp.

Now ive had the new 3kw sub running from my 300w amp for a few months now and its definalty not the same as my much older 600w sub. it doesnt seem to be as loud or punchy. (both are 12")

So, im guessing the reason behind this is because the amp is nowere near powerfull enough to run the sub?? is this likely to be the case or the loss in volume between my old sub box and the new one.

Anybody have any thoughts? i still have my old 600W sub, so im thinking of putting that back into my sub box.

Adam

 

[MK3]

Have you fitted your new sub into your old box? Or isit still in the one it came with?

 

[a.jenkin]

No, the box it came in, so the 3000w sub is in the slightly smaller box which is fitted to the sidewall of the boot.

 

[RossM09]

amp is way underpowered by no question of a doubt, and it wont do it any good, massivley under powering a sub will damage it, is the pioneer subb 3k watt max or constant/rms? if its rms ul need a seperate battery and split charging unit if its max and only like 1000watt rms u just need a much better amp and maybe a power capacitor. you can probs get a amp at a decent price off ebay i would say look at jbl gto range for good performance and price mate if u wunna power the pioneer well

 

[Lyons]

amp is way underpowered by no question of a doubt, and it wont do it any good, massivley under powering a sub will damage it, is the pioneer subb 3k watt max or constant/rms? if its rms ul need a seperate battery and split charging unit if its max and only like 1000watt rms u just need a much better amp and maybe a power capacitor. you can probs get a amp at a decent price off ebay i would say look at jbl gto range for good performance and price mate if u wunna power the pioneer well

No, no, no.....

What we need to know is, what sub did you have, what sub do you have, what amp are you using and what are the volumes of the new box and the old box.

3000watts RMS would be an absolute monster, i very much doubt you mean what you say. It's the same old problem with manufacturers like pioneer writing 10000000000watts on the side of their 150watt RMS subs. RMS is the only thing that matters at this stage.

Find out; the RMS of the new sub, old sub and the amp. This is the only way to come up with an answer to why it's not as loud.

Also, if the new enclosure is much smaller than the old one then it could be stifling the sub, causing it to have a lower output.

The chances are the new sub is a pile of poo, hence why you got it for free....

 

[Lyons]

P.S - Could you put a picture of the new sub box up? Just out of interest

 

[Struggler]

just for starters,

underpowering a sub, will in no way harm it what so ever!
you underpower a sub everytime you turn the volume down!

and adding a powercap will be a complete waste of money.
they're over marketed crud that are useless in 90% of cases, look at the science behind how capacitors work and you'll agree.

now we've got that cleared up.

a 3000w sub will have a recommended box capacity, (probs quite large)
undercutting this too much will play an effect, as its not the correct amount of air the sub should be working with. Is the box porter or sealed?? since it only seems to be a small box, i'd assume sealed, however best check, if its not a sealed box, bin it, a small ported box would be awful for a large sub.

is the sub box sealed?? mounting it in wood simply pushed up against the edge of the boot will create horrible cross phase (where opposing sound waves effectively cancel each other out).

Do you know the wiring set up of the sub?? is it dual voice coil and what is the impedance of each coil? make sure it is not wired to a massive impedance and therefore only running off a fraction of the power.

also the fact that is can HANDLE 3000w, means its a lot heavier duty a sub. so using a small amp will in fact be quieter due to the voice coil being heavy duty than a more efficient 600wrms sub.

the high power handling does not mean it will be loud, these are figures printed to help you match the amp to the sub.

Personally id say find a sub to match the amp, (or of course an amp to match the sub) but as said, make sure its the RMS figure you're working with. max power figures are just for chavs to boast to 14yo girls in mcdonalds carpark.

the RMS of the sub, should be abit higher than the RMS of the amp, and wired to either 2ohms or 4ohms (which ever the amp is stated to handle)

or of course the sub may just be fubared!

post up the what the amp is, what the sub is,
what the headunit is, what the wiring is, and how big the box is
(all of these will make a difference)

 

[Lyons]

just for starters,

underpowering a sub, will in no way harm it what so ever!
you underpower a sub everytime you turn the volume down!

and adding a powercap will be a complete waste of money.
they're over marketed crud that are useless in 90% of cases, look at the science behind how capacitors work and you'll agree.

now we've got that cleared up.

top guy!

I think the problem here is this "3000watts" bit, it's unlikely he will have be given a free sub of 3000watts RMS! It's probably a crap sub with some ridiculously over rated "max power" figure written on it, no true reflection of the capabilities of the sub...

 

[RossM09]

well i do apologise although i got told under powering a sub will damage it by a guy who runs a audio centre and deals mainly will jl audio, orion, genisis and focal so i thought he would be right when he told me this although i questioned it by what you just said.

 

[Struggler]

true say!

RMS is the only figure worth paying attenetion to.
but even this figures can be over done!

look up the loudest.com
www.theloudest.co.uk
best example! obscene max power ratings, but awful RMS values!
and ive heard them, they produce next to no sound, and what sound they produce is dire!

though pioneer are quite a reputable brand so don't think they'll be too over exaggerated

 

[Lyons]

well i do apologise although i got told under powering a sub will damage it by a guy who runs a audio centre and deals mainly will jl audio, orion, genisis and focal so i thought he would be right when he told me this although i questioned it by what you just said.

The guy has a point, although the way he/you stated it was wrong.

You "can" damage a sub by running it on an underpowered amp, just as you can damage a sub by using a very powerful amp.

All amps have a maximum output power which they cannot exceed, but turn the gain (volume) up too high and it will try to exceed this level and "clip" meaning the sound waves get the top chopped off them. this means the sub pushes out, stops briefly, then pushes in, then stops briefly, then pushes back out etc etc. The bit where it stops causes damage long term as the voicecoil does not move, just get's hotter. This heat can eventually cause damage to the voice coil, sometimes making it melt :evil:

And thats HOW an underpowered amp "can" damage a sub....and that's HOW for NOW! :star:

http://en.wikipedia.org/wiki/Clipping_(audio)

 

[Struggler]

yes, (though putting the words gain and volume next to each other saddened me! gain is for setting the input of the amp to match the output voltage of the headunit. Amps are designed to amplify up to a cetrain level, however headunits kick out different voltage output, and the amp need to know what the input voltage is otherwise it will amplify past the level it is designed, and run into a clip).

if you use a small amp on a big sub, and try to compensate for the lack of sound by cranking the gain on the amp up to compensate for the lack of volume will run the amp into a clip.

this will turn the smooth sine wave that makes the cone slow down to a stop before changing direction to make the next sweep, into what looks more like a square wave, where the wave goes almost vertically upward, then has a sharp angle around 90deg before going flat, then another sharp angle before going down again. Its the sharp change in velocity of the cone that damages the voicecoil, along with the heat.

this will put alot of strain on the sub and end up stretching the coils knackering the sub. even though it will sound quiter that the 600wrms sub!

however i stand by my guns, an amp set up correctly, and not running clip,
cannot harm a subwoofer that has an infinatley higher RMS power handling that the output of the amp. So long as the amp is set up with an oscilloscope, no harm will come to the sub (unless is a tiny, lower power handling sub).

Also, damaging a sub by underpowering, is not the same as damaging a sub by over powering it,
when you overpower a sub, you force over excursion, where the sub effectivly goes out too far on each sweep. also known as backplate spanking (because the cone will hit a plate at the back off the sub because its going too far! and too fast!) this is create huge amount of heat and snap the coils.

 

[Lyons]

yes, (though putting the words gain and volume next to each other saddened me!

Apologies, I didn't want to go into tooooo much detail for people who don't know what an amp looks like!

Looks like we've scared a.jenkin off anyways!

 

[a.jenkin]

yikes! i've just re-visted this thread to give an update and found loads more replies!!

So an update! I have put my old sub (600w) into the fitted box with my 300w amp and its sounding better, I think the woofer is being powered much better.

Now it however doesnt sound as good when it was in the old, square, sealed box. I think there are 2 reasons for this...The new box is smaller and it is also ported.

I suspect the box being ported is the main problem. Could I seal it up from the inside or would this be difficult to get a good seal?

FYI, I have taken some blurry iphone photos of the 3k sub.

Thanks for all the info guys!

 

[Lyons]

Lol, that's a decent sub, especially for free!!!

Get a picture of the old and new boxes up too, the volume of them is the key to how it sounds. Also the home made ported box may not have been designed correctly and therefore doesn't sound as good. Ported boxes have to be properly designed and tuned to make them sound good. Sealed boxes just need to be the correct volume for the sub and very rigid.

I can't give you any specific answers or advice without seeing the boxes

 

[Lyons]

Just looked at the sub properly, It's a TS-W3004SPL and needs a lot of power to run it well, and a well designed box! Your amp needs to be at least 3-4times more powerful!

I have heard stories about these being a bit of a pain to make sound decent. I would flog it and stick with your old sub.

 

[a.jenkin]

Thanks lyons, (sorry for delayed replies - I keep forgetting to subscribe to thread!).. some pictures of the old box can be seen here:-
http://s588.photobucket.com/albums/ss321/anjenkin84/SubForSale