3-Way capacitor less cross over question...

[binspaul]

Hi,

I would like to design a 3 way passive cross over using inductors and resistors. I am using the model based on the US patent No: 6115475 (By Diaural). The component values required are: 1mH Inductor, 0.25mH Inductor and 8R Resistor. What all factors should be observed in selecting the components ?

Best regards,
Bins.

[Inductor]

Originally Posted by binspaul

Hi,

I would like to design a 3 way passive cross over using inductors and resistors. I am using the model based on the US patent No: 6115475 (By Diaural). The component values required are: 1mH Inductor, 0.25mH Inductor and 8R Resistor. What all factors should be observed in selecting the components ?

Best regards,
Bins.

The idea behind this xover is to make a series 1.order xover in a "capacitor-less" fashion.
In the same fashion (parallel) a "coil-less" xover is possible if you use a parallel 1.order xover.
There's nothing new in here to patent. Only a series first order xover, like everybody else's. You can design (speakers drivers and xover components) for a xover (in mind), but that would be stupid, if not achieving anything else besides theoretics.
Go see the vintage Dynacos A-25, Pioneers, car audios, for easy to implement 1.order xovers, series or parallel.

(Shown here T-shirt of the patent, of a "capacitor-less" xover, with a parallel 1.order xover with plain cap on tweeter, as on it's second page)
US Patent 6115475 - Capacitor-less crossover network for electro-acoustic loudspeakers
http://www.braindex.com/t-shirt-for-...eric-096116709

[binspaul]

Hi,

See the patent paper below. I would like to design a 3 way cross over for my speakers. What all speaker attributes should be considered while designing a cross over ? Which one is the best - First order or Second Order ?

Best regards,
Bins.

Originally Posted by Inductor

The idea behind this xover is to make a series 1.order xover in a "capacitor-less" fashion.
In the same fashion (parallel) a "coil-less" xover is possible if you use a parallel 1.order xover.
There's nothing new in here to patent. Only a series first order xover, like everybody else's. You can design (speakers drivers and xover components) for a xover (in mind), but that would be stupid, if not achieving anything else besides theoretics.
Go see the vintage Dynacos A-25, Pioneers, car audios, for easy to implement 1.order xovers, series or parallel.

(Shown here T-shirt of the patent, of a "capacitor-less" xover, with a parallel 1.order xover with plain cap on tweeter, as on it's second page)
US Patent 6115475 - Capacitor-less crossover network for electro-acoustic loudspeakers
T-Shirt for US Patent 6115475, Invented by Alexander; Eric

[Inductor]

Originally Posted by binspaul

Hi,

See the patent paper below. I would like to design a 3 way cross over for my speakers. What all speaker attributes should be considered while designing a cross over ? Which one is the best - First order or Second Order ?

Best regards,
Bins.

Yes, you should consider all the speaker attributes. When designing we star looking at Re and Le, at output in frequency and phase in frequency and Fs. Also important between the drivers dispersion/polars. For woofers there's some work related with to the best enclosure. The xover/filter is the main component here, you should buy a 101 book or read a lot on the Internet on the basics, if you are interested.
Series vs. Parallel Crossover Networks
Procedure: Design Crossover
Lenard Audio - Education - X-overs. Time Alignment.
JBL Professional Sound System Design Manual - Pi Speakers - unmatched quality and state-of-the-art performance
p Speaker Crossover Document illustrates the operation of passive crossovers and filters - Pi Speakers - unmatched quality and state-of-the-art performance
Newbie Speaker Builder, Need Some Resouces.

[wolf_teeth]

Make sure she can handle some current!!! It's going to have to be a very high wattage resistor to work well.

The Acoustic Reality Series Crossover, AR-SXO



When Peter "Friend" on the old Mad-Bored introduced this topology, he even showed a picture with the cap-less xover implemented, and the C1 resistor was a 100W Arcol or Dale panel-Mount type with heatsink case mounted EXTERNALLY to dissipate the heat.

I have external xovers on my Scandivifias, and tried it with the purposely bought 100W Arcol, and it got substantially warm. The other thing you will notice is that the resistor will effectively nuke the woofers' Fs magnitude. You might want to remeasure out of box the T/S of the driver with the resistor connected, or even in the network as a whole to make sure your box tunings and such don't change.

FWIW- I didn't like what I heard in my 'trial', but I didn't change the box situation either.

Good luck!
Wolf

[bobodioulasso]

What a waste of power!

[wolf_teeth]

That is indeed a waste of power. It cut output as well as the driver Fs. That's really why I didn't like it.

The cap was reinserted in the design and left there.
Later,
Wolf

[Inductor]

Let's post a Diaural type xover - SERIES

I used (drivers from Visaton) the same xover components as in the pic of post #5. For this simulation, and as you can see the tweeter benefits from being of low impedance and "low" SPL (low value resistor). The woofer is kind of "short" and benefits from doubling (2 woofers in series for better output) or/and raising the impedance from 8 ohm up and/or higher SPL.

(On the first pic we have the xover, second pic the electric output to drivers and on third pic the freq. output).

[Inductor]

Now let's post a similar Diaural type xover, but now an equivalent typology - PARALLEL

Note: This simulation of a series and parallel 1.Order, 6dB/octave xover, doesn't try to duplicate any speaker or brand. For, is just a study to compare two different and equivalent typologies of xovers.

[wolf_teeth]

Nice to see that they differ, but not heavily.

I've often wondered about this one..
L C Audio Technology / Series Filter



It's a different layout, but basically the same thing. The tweeter is 12dB, but I never quite got what the resistor on the link-wire did. The tweeter is already padded with the other resistor,so it kinda seems redundant.

What say you/
Later,
Wolf