Replace crossover in existing box

[ccdoggy]

So i seem to have allot of time on my hands right now and am trying to upgrade my Aperion audio Intimus 532 speakers (actually they are old edge audio speakers but edge changed into aperion). Pretty generic drivers with a Vifa tweeter and 5" woofer.

The crossover that is currently in it has 1 air core inductor, 1 iron core inductor and a resistor (does this seem right? shouldent there be at least one capacitor?). Now i know about crossovers and what not but never actually tried building one from scratch. what would you suggest to get me started on upgrading the current crossover?

Thanks for the help.

Im also in the process of getting the necessary parts to enABL the drivers.

[planet10]

Post some pictures? Inside & out... and a pic of the XO. The described component complement is somewhat strange (it is possible to put a 1st order XO on a tweeter with a shunt inductor but it is not very common)

dave

[ccdoggy]

ill get pics up asap, once my roommate come back with a good camera.

I also need to pry the crossover out of the box, it seems to be glued in there with some pretty strong stuff.

I take that back, its 2 resistors not one.

[ccdoggy]

[planet10]

can you take a black felt-pen and draw in where the componenets connect on the back side of the circuit. Can you also take pics of the cabs & the drivers. And i'm wondering if there is a cap connected directly to the tweeter terminals.

dave

[gfiandy]

Hi,

I have drawn out what I think your crossover must be and it is very unusual.

It appears to use the the first inductor as a LF bypass for the tweeter in combination with the resistors.

It also uses the same inductor as a HF block for the woofer incombination with the resistors and a further inductor.

I am at a loss as to why they decided to do it this way but it is interesting none the less.

If you don't have any measurement equipment I wouldn't mess with it it would be very difficult to predice what results you will get.

I would be interested to know if anyone has seen this before or if I have worked it out wrong which is quite possible.

Sorry for the very rough diagram I only had paint available to draw it

Regards,
Andrew

[ccdoggy]

No caps anywhere. I may have access to a multimeter that does measure just about everything, depends on if my friend is willing to share.

The speaker is supposed to have a impedance leveling tech.
From the site:
"HD-X3™ Impedance Leveling Crossover Technology

Aperion's patent-pending HD-X3™ Crossover Technology levels the impedance load across the entire frequency range, creating a remarkably flat frequency response and eliminating the detrimental effects of resistance introduced by long runs of speaker wire. In English, this means that no matter if you have a traditional home theater or your entire house is wired for sound, the performance will always be fantastic without spending a king’s ransom on speaker wire. "


Suggestions/Ideas?

[gfiandy]

Hi,

Well they are right it will level the impedance, but it is a very brute force way to do it.

Basically the two 15R resistors in parrallel form a 7.5R load in parallel with the woofer and in series with the tweeter.

This means that at low frequencies at least the impedance will never rise above 7.5R but will fall to arround 4R assuming the bass driver is 8 ohms.

The cost for this is that almost 50% of the power going to this speaker is wasted. Hence the need for 2x 25W resistors to be able to dissipate upto 50W.

I doubt this is the best sounding configuration that could be arrived at with these two drive units and you could definately find a more efficient one.

However as I said earlier without measurement equipment the best you can hope for is something that limits the bandwidth to both drive units.

A Xover that would do this could be made with a series 0.5mH inductor on the bass followed by a parallel 33uF cap. For the treble a series 3.3 uF cap followed by a parralel 0.3mH inductor and probably an L pad of 3.3R and say 15R.

This is just some values that will probably be in about the right ball park. They will not intergrate properly and the phase will be messed up. But if you just want something to try this probably won't sound completely broken.

To try to trim this I would adjust the two caps to try to get the midrange balance to sound right the bass 33uF one first and the 3.3R resistor to adjust the treble brightness. (smaller for more treble larger for less) if you feel it is peaking right at the very top then reduce the 15R

I say again, this is not a correct crossover it is just some values that may work, they are typical of the kind of values for these type of drive units.

Regards,
Andrew

[marchel]

I've read articles about the edge/aperion audio's XO circuitry.

As I've understood it, They use some sort of minimalistic series Xo, and uses no capacitor , instead they use a resistor and an inductor to form a high pass filter.

I think you got the schematic drawing wrong. I'm not sure though.

[ccdoggy]

When you say measurment equipment do you mean to measure the drivers or the components for the crossover.

I got the T/S for the tweeter and the woofer, given they are not perfect but im not going for perfect.