Inexpensive 12 inch paper cones vs poly and carbon fibre etc

[Circlotron]

We all know that you get what you pay for and this is true for speaker drivers too. If you want good perfomance from a conventional passive system you need to use good quality drivers. What I want opinions on though is the following approach to making a sub - There are these moderate to cheap (not rock-bottom junk) drivers that I am looking at -> http://www1.jaycar.com.au/productVie...=&SUBCATID=383 and while I realise that if you just stick them in a box, they are not going to set the world on fire the same way a $1,000 driver would.

OK. Lets say we put the above driver in an 80 litre sealed box and equalise the living daylights out of it so it has no choice but to do as it is told. i.e as the frequency goes down the cone displacement goes up in more or less the same manner a perfect driver would, down to say 20Hz, within the mechanical limits of the driver of course. Also, lets put an upper frequency limit of ~100Hz so the cone is reasonably always moving in piston mode, not breaking up into a series of wavy wiggles across it's radius.

Now, the question is this - should I expect a very great improvement in performance so that if a very high quality driver was used in place of the one I am talking about, would there be not much difference in results? i.e can I make a moderate quality driver behave like a very good one, at least as far as frequency response is concerned, *over a necessarily limited range*, provided it has reasonable X-max?

[Volenti]

I've used those jaycar paper cone woofers before, their not too bad.

Probably the main difference between the heavily EQ'd budget woofer and a "natural" high quality woofer would be potential volume (loudness), though the budget woofers can sometimes have efficiency working in thier favour.

There's other factors like how linear the woofer behaves, transient response ect that need to be considered as well.

[Nappylady]

Qts of 1.46.... IIRC, doesn't high Q like that usually associate with sloppy, "boombox" bass?

...probably do well with a dipole...

also, the sensitivity is only 89dB, and my personal tastes try to stay above that... however, I'd be interested in seeing what you did with this driver... I'm interested in all projects.

Good luck, let us know what you end up doing.

[ronc]

With a Qts of 1.46 i would not expect a "fast" bass. I have always preferred a lower Qts that will keep up with a fast mid or full ranger.About the only thing you can do , as far as an enclosure, is an aperiodic port with the cab volume .75 x Vas and even that may not help.Try an OB if you have the space.
ron

[JoeBob]

My guess is that if you slap that in an open baffle, add a little EQing to it and you'll probablye be amazed that it sounds as good as it does for the price.

[ThomasW]

The driver is designed to be used as a woofer in a 3-way not to be used in a sub

The "Q" is way to high. The Fs is 32Hz (= BOOM BOX).

The 50 watts power handling is a joke in this day and age. It's not going to handle any reasonable amount of EQ with this wimpy VC.

Interesting that they don't list the Xmax.

This driver should retail for $14.95

Save your money and get something better......

[ronc]

Yea , i love some of the cheap car amps that have"400 watts/channel". I tried to explain to a guy once that the output power was more than the input by a wide margin and he would not believe me LOL.
ron

[JoeBob]

Usually more expensive is better. But power handling is usually what you pay for. A 32Hz fs isn't excessively high, hell, response down to 40Hz is enough for many music listners. And the Q is high, which is good for some arangements, not so good for others.

And as for the EQing you could aply with 50watts, well that is more than enough if you've got a small room, afterall no way will it be reproducing 35Hz continous at 50 watts, and the driver will be able to tolerate more than that peak anyways.

It's good to advise someone asking a question, but in truth none of know how it will really sound, we can only guess.

[ScottRHinson]

Originally posted by Circlotron
Now, the question is this - should I expect a very great improvement in performance so that if a very high quality driver was used in place of the one I am talking about, would there be not much difference in results? i.e can I make a moderate quality driver behave like a very good one, at least as far as frequency response is concerned, *over a necessarily limited range*, provided it has reasonable X-max?

Kind of, and not really. Frequency response wise you could get it to do almost anything you wanted it to, given it did not excede it's excursion limits. You've already alluded to that. However, there are some things you can't correct with only frequency equalization. Linear and non-linear distortion will be quite high for even low power levels. I'll post two plots, 135Hz 150Hz and 165Hz IMD distortion measurements for a $12 5.25" woofer and for a $150 world class 5.25" woofer.

First the cheap one...

[ScottRHinson]

Here's the expensive driver. Remember, only the tones at 135Hz, 150Hz and 165Hz were put into the driver. Any other tone showing up is a distortion....

Now there are expensive drivers that don't do as well as this one and there are inexpensive drivers that do much better than the one I posted above. (There are only a select few I've measured that do better than this guy.)

Scott