Hey Guys,
I currently have 2 x RF P1 12" subs in the boot running off a RF 3001 monoblock, getting about 150wrms each(which is the rating).

Now i was thinking on the way home, would there be much difference if i changed to a single IDMax12" D4? It could get upto about 380wrms (rated 350wrms).

Would the following change much?
- Volume
- Sound Quality
- Response time of the sub: eg, how quickly the sub can play notes and recover.

Cheers people

Get the IDMAX 12" ... you know you want to
Solid sub for SQ dude! :thumb:

Well, that depends on efficiency, Xmax, and enclosure tuning. All being equal with the same power but half the cone area you'll have 3dB less output, but if just one of those variables is different - which I'm sure will be the case - then it will possibly be more or less than 3dB difference in output.

I haven't checked but I assume the ID Max offer more total Xmax, but is it twice as much of the P1? It will need to be (efficiency notwithstanding) to achieve the same output if the same style of box is used. But are you using the same box? If not then a ported box may make the difference.

There are so many variable I hope what you learn from my post is that there is no true way of saying how one ID Max compares to two P1, but I have always believed in cone area before all else when SPL is concerned.

edit: what Damon & I have said

It all will depend on the amp i.e damping factor, power and so on. the higher the damping factor the more controlled you sub becomes.

e.g. my single 10 which handles 450wrms (manufacturers specs) is getting 1000wrms. the damping factor the amp has is greater than 300.

if you had deep pockets you could get an amp that has a damping factor of greater than 2000 and 1050wrms 4ohms (now thats control).

read HERE

the IDmax does not need a great deal of power to run effectively. ideally you would want 500wrms+ but 380 will still get it going well. i have one and for temporary resons im running 140wrms to it. very mediocer indeed, yet i find it is still loud enough for moderate sq purposes. as damon and ICACHA have said the amps will effect way the sub plays, however to what extent im not sure (lets not take that any further please! ha ha) and the subs xmas and efficiency play major roles in the overal outcomes of the sound from each sub. if its personal choice then your the one thats going to have to decide. me personally i would go the IDmax over the 2 RF subs. but then thats me ...

why would u want 500+ when it has an RMS of 350?

Just cause it's RATED at 350WRMS.... don't mean it can't take anymore juice!

lol, my bad, all this time i am thinking about the IDQ12" D4, not the IDMax12"

So how would the 2 RF's compare to the 1 IDQ please?

IDQ = about 1.8x the xmax of both RF's combined, has just over twice the rated rms, so i take it all being equal volume would remain relatively unchanged?

ICHACA... i dont want to clog up this thread with my usual garbage So all i'll say is, if you could one day write a peice so we can read it on why you beleive uber-high damping factor does what you claim it does, i'd be most appreciative, especially if you can present some actual physics to go along with the heresay

On with the thread

it was only a matter of time. haha. i did say lets not take it further but oh well lets go, the gloves are off. nah just kidding.


with one IDQ spl wont be able to reach the dB what 2 RF subs can do. from a SQ point of view the ID should still be far supirior to the RF subs. while i havnt heard them (IDQ) im making my judgments based on my ID max and from what others have said about them. and yes 380wrms should be plenty to get that sub pumpin! and also the IDQ only needs a small box, i think it was 0.8cu.ft.

control, headroom

e.g. my 10" rated (supposedly 450wrms) driving it with 1000wrms claimed by the amp manufacturer.

hey Blackie, you think thats a bit of over kill? I have to say it sure sounds bloody nice. oh and my fronts which are rated at 100 or so rms are getting 320wrms i wonder if that would be over kill too

i just love you guys that are into the theory side of things

i throw the book away and do what works and keeps on working

Considering my front stage will be getting a tad over 1100wRMS, i beleive you may be barking up the wrong tree in this instance


I'm not 'into the theory side of things', you make it sound like all i do is sit round all day reading text books rather than selling gear...

You know what i think about super-high damping factors and claiming that they make up for power etc etc, all i'm asking is for some sort of reason why you think it SHOULD work... every audio engineer i've talked to about the matter seems convinced that the differences due to damping factor are inaudible roughly once its 100 or so, perhaps 250 to be on the safe side... so all i'd like to see is some logical reasoning as to why they are wrong

I'm not being sarcy or taking a dig at you, i'd just seriously like to see the reasoning, so many claims get made without proof or backup and i'd just like to be sure there is some in this case

Peace

i never have, and prolly never will, see the point on running a speaker or sub with a amp rated twice the power on half gain. headroom is a waste in my opinion, and thats an opinion

back on topic please?

Because watt ratings are arbitrary. In reality, what your speaker can handle depends on the time it has to handle it and a host of other things, and the rating stamped on it by the manufacturer is just a guide to ensure longterm reliability... Speakers rated at 100wRMS can HAPPILY take 1000wRMS for a splitsecond (box dependant) on a transient if its available. You can never have too much power

Sure. The IDQ is an infinitely superior sub from an SQ viewpoint to the P1's, but the P1's will most likely get louder. If you want a bit more loudness, then perhaps try a DD 1012 or 2512 etc, both of which sound nice in the right box and can both crank

you know we wouldn't even be getting close to those numbers even is we wanted to, its all about control and headroom nothing more and nothing less.

your cool (meaning that i don't hold anything against people) this is the internet and thats all...

i know damping factor isn't everything, i know that damping factor changes with resistance i.e. speaker moving up and down which causes resistance changes in turn changing the damping factor. cable resistance and length also will change the damping factor. although i did jump into it a little quick i might add

Physco,
This thread is getting very confusing to read. What do you want? You are saying SQ but then say you want 300+ RMS to get it there? CAASQ in Shineys car runs 1 sub that sound like about 50wrms comming out of it e.g. not bloody loud. Bring your car around to colins some time (as I havn't herd it!!!!) and I'll fix you up mate lol!
Mick

lol, ill be there soon mate

what box are the Rockfords in. If it is the Rockford 'Loaded' enclosure then a single 12" isn't going to come close to it in SPL. The P1's arnt a bad sounding woofer but i would imagine (never heard one in the flesh) the IDMax12" D4 would sound better.

I havent actually heard an IDQ12, but I've heard a hell of alot of good about them. I've looked at online consumer reviews, asked on the forums, asked some knowledgable people from a certain four-letter worded store and gotten pretty much the same recommendation... that for SQ performance for the price, an IDQ12 is damn hard to beat.

Was going to get one myself, and went so far as to actually order it, but then unforseen circumstances led me to an IDMAX

Also, the IDQ has quite a high Xmax as well. Sure it wont compare in that respect to an IDMAX or RE XXX, but quite good still.

I'd recommend them

p.s. another big plus is they are generally said to run hapilly in very small enclosures, thus giving you bonus boot space