DiAural X-over (1 Viewer)

[Scott Simonian]

I was looking back at one of my earlier WSR magazines and read an article on Kimber Kable. In this article, he mentioned and described a different type of crossover; or the DiAural crossover.
I dont know a whole lot about it. Basically, the crossover uses zero capacitors and by doing this, it keeps a very linear phase. (I dont think that was the right wording.)
***In a regular crossover, the inductors and capacitors will alter the phase of that particular frequency and alter the sound slightly.***
Im not going to go much further because, I dont really know my stuff yet on X-overs and I dont want to give out incorrect information.
Anyway, does anyone know anything about how to build a DiAural crossover. I went to the website
here.
This website had nothing on it whatsoever. If you can pick up this issue of WSR, (I forgot the month, it has Pearl Harbor on the cover). EDIT - January 2002
I really would like to build this kind of crossover. Maybe it will bring me back to music too.

 

[Scott Simonian]

Heres the article
************************************************** ********
The DiAural Crossover
I’ve decided to save the best for last.
visited Kimber Kable with the expectation
learning more about their cables. What ultimately
got was much more than what
expected. Not only was I impressed with
their cable designs and manufacturing,
what absolutely caught my aural attention
was Kimber’s DiAural circuit (www.diaural.com)
, implemented in a series of prototype
loudspeakers (yes, Kimber does have
capability to design and build loudspeakers),
as well as a set of Aperion Audio satellites.
The patented DiAural circuit is so simplelooking
in design, consisting of just wiring,
resistors, and inductors, yet functions
manner that you experience sonic imaging
in ways you very likely would never have
anticipated.
According to Kimber, in theory, such
circuit design should not have worked.
what Ray and his team discovered was
only did it work, but it functioned amazingly
well, delivering sonic images that seemed
to be a dramatic improvement over those
resulting from conventional crossovers.
why did such a perceived refinement
sonic imaging quality occur, rather than
predicted setback? Again, Kimber’s team
set out to justify, in a quantifiable manner,
their listening observations. What they discovered
was that the DiAural circuit,
conventional crossover, appropriately distributes
power to each of the drivers.
the DiAural goes much further. And to
understand this, I need to explain, based
Kimber’s rationalizing of how and why
DiAural design works.
A recorded sonic signal is typically
amalgamation of sounds of various frequencies. Let’s take the simple case, for which
you have a high frequency sound, and a
low frequency sound, both of which are
being recorded at the same time. The
recorded signal is neither the high nor the
low frequency sound per se, but really is the
result of combining these two frequencies.
And so what you hear isn’t the two native
frequencies in the recording, but rather the
net effect of combining/mixing them.
In the context of this simple scenario, with
a conventional crossover, what happens is
that you don’t hear, for example, the high
frequency signal coming out of the tweeter
as a pure waveform. Rather, you’re hearing
the high frequency component, with the
effect of having combined with the low frequency
waveform. Conceptually, this should
compromise the capability to listen to the
native pitch and phase of this frequency
component, just as they were before the
recording. Theoretically, the only way to be
able to do so, is to subtract out the effect of
the low frequency signal on the high frequency
component, and not just attenuate
the low frequency signal.
And, in fact, this is what Kimber says is
accomplished with the DiAural circuit. As a
series circuit, power cannot reach the low
frequency driver without being a part of the
path-of-power for the other drivers. Kimber
believes that as a result of the interactivity
within this path-of-power, the output is a
restoration of each instrument’s (or voice’s)
original waveform shape, as they existed
before being mixed during the recording.
Kimber is further investigating whether part
of this interactivity is the subtraction of the
effect of the low frequencies from the signal
sent to the tweeter (and midrange, if a
three-way system), due to the interaction with the inherent back EMF from the woofer.
Kimber also claims that the DiAural circuit
offers a number of other advantages over
conventional crossovers. Capacitors enable
crossover designs with desired roll-offs, but
also can alter phase relationships between
spectral components. Kimber asserts that
with no capacitors in the DiAural design,
such phase relationships are much better
preserved in the recording. Additionally, the
low and high frequency drivers are wired in
series, as opposed to the more common
parallel crossover designs, again helping to
maintain the tight phase relationship throughout
the sonic spectrum. A common reaction
from observers, when the circuit is first
described to them, is that the tweeter will
suffer damage without a protecting capacitor.
However, the DiAural circuit uses an
inductor of low DC resistance, shunted with
the tweeter. This, along with the back EMF
of the woofer, combines to yield a system
wherein the tweeter is nearly burnout-proof.
Ray Kimber and I spent nearly four hours
in an evening, listening to a variety of twochannel
music from CD, through his prototype
two- and three-way loudspeakers that
use the DiAural circuit. Electronics and
amplification were from Krell, and, of course,
Kimber’s high-end audio cables were used.
What I heard was both breathtaking and
awesome with the resolution of sonic imaging.
With just two loudspeakers, I was able
to discern sounds that imaged far beyond
the physical locations of the loudspeakers,
and sometimes all the way out to the sides
of my head (the loudspeakers were placed
at a 70-80-degree included angle relative to
the listening position). The spatial placement
of sonic images was so distinct, so
easy to detect, both between and beyond
the loudspeakers. We also experienced
some movie soundtracks through an Aperion
Audio (www.aperionaudio.com formerly
EdgeAudio) 5.1 setup, consisting of five
identical satellites using and a subwoofer.
With this seemingly modest setup, the rendering
of three dimensional soundstages
was remarkably wide and deep, and also
very impressively seamless. I look forward
to future evaluation of loudspeaker systems
using the DiAural circuit. Kimber has said
that loudspeakers that use his design have
restored his joy of listening to music.
************************************************** ******
Since that website didnt tell a lot, maybe you can get some REAL information from this talk from WSR.
P.S. Sorry for the skinny column, I had to rip it off the .pdf from the WSR website. Thank gawd I subscribe!

 

[Anthony_Gomez]

Go to madisound and ask about Friends (normal vs. capacitorless) series XO. His XO was a big topic a month ago

 

[Patrick Sun]

So...how about giving us the Cliff's Notes version of the discussion?

 

[Anthony_Gomez]

go to
www.acoustic-reality.com
enter the site and click on AR-SXO (link is on the top right)
scroll down 1/3 of the way for a review/simulations by John Kreskovsky (super big wig at madisound). It will be one of the red CLICK HERE links

 

[Mark Hayenga]

DiAural, and most series networks, are silly and a waste of time. I also wouldn't trust the word of any boutique cable manufacturer if I really wanted to know how anything in audio worked. There's getting to be way too much of the high-end hype in DIY these days.

 

[Scott Simonian]

Mark, what makes you say such things? Have you heard a DiAural or series crossover in a speaker before? No good? I havent heard it yet. Looked promising.

What was wrong?

 

[Mark Hayenga]

I've never heard a "DiAural", but I've heard (and designed a few) series crossovers before. The problems implementations such as the DiAural have are due to low rolloff slopes (esp first order series xo's) resulting in a lot of driver overlap and increased tweeter distortion since the tweeter is usually only down 10-15dB by its resonance. Parallel networks are also much easier to design since you can treat each driver independently. Just poke around a bit on DIY forums such as the Madisound board, if you can ignore all the hype and look at what these type of xo's actually accomplish you'll wonder why most people ever fool with them.

 

[Scott Simonian]

Yeah, I had an idea that those were some of the cons for a "series XO". I just thought that the problems would magically disappear with it.
Hey, Im just looking for something that sounds good and I know that is possible with a regular XO.
Plus, capacitors are cool.

 

[Alexis]

www.aperionaudio.com uses these crossovers.

 

[Mark Krawiec]

Anthony's link is a good one.
Here's an easier way to get there.
the moral of the story is that, while good series design works, there's nothing at all superior to the series xover and in fact, they have drawbacks as noted.
mark is right here-too much hype.