The Heavenly Connection DIY Speaker Cables
(Our long time associate Lewis Muratori crafted and contributed the following
article to the Melbourne Audio Club monthly magazine. Lewis is an
erudite, intelligent and experienced lifelong audiophile, who has experimented
at considerable length and in considerable detail in this and many other
DIY audio areas. We thank him warmly for allowing us to reprint
excerpts from his original work, as follows).
As we all know, there's an outrageous amount of hype, New Age Physics
and, frequently, nonsense directed towards the paranoid, obsessive-compulsive,
dollar rich set known collectively as Audiophiles.
I enjoy a laugh as much as the next guy, and I am sorely tempted to aid
and abet this confusion by offering even more dross and magic. However,
following are the bland facts, wholesome and unembellished. I sincerely
hope my article encourages you to experiment, as cables do make a difference.
Andrew, a good friend and audiophile, recently had a visit from a young
audio acquaintance who had constructed a set of unusual speaker cables.
The recipe for these cables is still freely available on the Net.
These cables sounded surprisingly good. In fact, they were
so good that Andrew immediately collected the vital ingredients and made
up one of the three sets needed to fully equip his tri-amped system.
Quite soon he invited me to audition these cables.
Andrew never exaggerates - quite the opposite, in fact. Like
me, he has more than a couple of decades invested in this "hobby".
So, when Andrew calls and suggests something I listen.
These cables were very interesting. They were unusual, yet compellingly
cheap. They looked like two lengths of 75 ohm co-ax connected between
amp and speaker.
Imagine we have two pieces of 75 ohm co-ax lying parallel in front of
us. On the LEFT cable end, the PVC sheath has been trimmed back
2cm, and the braid pulled back and twisted together. The central
dielectric, (in this case the pentagonal "air" type rather than
the foam) has been trimmed back about 1cm. There is 2cm of copper braid
sticking out to the side and 1 cm of solid core copper sticking clear
out of the end. The RIGHT cable is trimmed in a similar fashion.
Now, here's trick number 1. Take the braid from the LEFT cable and
connect it to the central conductor of the RIGHT cable. Take the
RIGHT cables braid and connect it to the central conductor of the
LEFT cable. Repeat this at the other end of your cable run.
You can see that each wire of each speaker cable will be both an inner
and outer conductor, but not from the same co-ax cable.
That takes care of the mechanics. In the Net design however, the
braid was instead a thin copper shield. This shield was left covering
the inner dielectric after an outer braid was removed from a particular
cable designed, I think, for microwave use. Andrew and I spent a
couple of days refining this original design by adding a few ideas of
Now, the methodology. Every configuration and/or material tried
was exhaustively auditioned and compared with a couple of references to
ensure we were not imagining things. Those who know me will be aware
of my healthy skepticism concerning all things audiophile. I have just
two audiophile requirements of any new idea:
* It can be demonstrated repeatedly both to myself and to a non-audiophile
to be an improvement AND· It delivers demonstrated value
Ideas which pass these tests end up staying in the system until further
notice. If it is DIY, then even better! Andrew's outlook
parallels my own. And it should go without saying that only one
thing was changed at a time. We listened in mono, as this halved
our workload, yet still gave us all the information we needed.
The system configuration was:
1. Amplifier- solid state
2. Speaker- large, full-range 3 way dynamic type
3. Stuff that didn't work - I'll spare you
4. Opinions- our own
5. Credibility - you be the judge.The first area of improvement we discerned
lay in the quality of the conductive elements. Some judicious hunting
unearthed an inexpensive coax with both a clean, and more importantly,
annealed centre conductor. This latter, in my experience, tends
to sound less grainy than the "work hardened" alternative. The
copper used in the original design was of a fairly low quality, bad enough
to leave even a neophyte audiophile unimpressed. Both Andrew and
I had experimented in the past with flat copper speaker cables, based
on unrolled "alpha core" inductors that we cut into lengths
and then shielded. Could we use some of this good quality material
instead? Well, yes, but the pile of 14 gauge material in our stash
was 30% too wide to wrap in a single layer around the dielectric. Stanley
knife and straight edge to the rescue, and we were ready to go.
Yes, it sounded far, far better, and yes, it was worth the effort.
The next problem was mechanical stability. After wrapping the copper
tape along the length of the cable it was obvious that we would need some
extra support to avoid cable kinks when bent. Of course, we also
needed an insulated covering for obvious reasons. The original design
used heatshrink over the whole thing, which worked well. But concerns
about the effect on the sound due to the heatshrink, particularly over
such a long length of conductor, led to a better idea. We used 3mm
nominal expandable cable mesh to cover the copper before the heatshrink
was slid on and shrunk (use the clear stuff). Approximately 6.5 mm internal-diameter
worked fine. This gave two worthwhile benefits:
* Kept the heatshrink off the surface of the copper ribbon; and· Introduced
a virtual air dielectric over the ribbon due to the open nature of the
And, yes, we did try it both ways, and yes, the braid did sound better.
Smoother, clearer, less background noise. The difference was surprisingly
obvious. Incidentally, the Alpha Cores should be marked for directionality.
Sounds best with the outer end at the destination i.e., speaker.
Design refinement completed, and both of us satisfied we had tried all
reasonable configurations and had finished with something pretty special,
we called it quits, compared grins, and had another chuckle at the expense
(pun intended) of high-end cable manufacturers.
The sound? This is a supremely musical cable. Its overall
character in the context of our systems is silky sweet, totally grainless
and harmonically rich, especially in the lower mids. Treble information
is extremely clean, aided by the cable's surprising dynamic capabilities
both at micro and macro levels and from top to bottom. Ah yes, the
bottom! Taut detailed, articulate, lacking any boom or bloat and
with superb pitch definition.
In fact, this cable contrives to amaze me even after enjoying it in my
system for some months. Many of its attributes remind me of the
effect that a good mains filter can have in a system.
Theories? Nothing concrete this end. Constructive input from
the more technically inclined is warmly invited 'cause I for one would
love to know why it does what it does so well.
Just to hand (June 2005) has come an addendum to Lewis' cable, from
Andy Redwood, in Melbourne, Australia. Andy, a good friend, has an AKSA/
Magneplanar system with active crossover, a very impressive system indeed.
Here's Andy's article offering enhancements to Lewis' original recipe,
and it is both easier to make and should give some sonic improvements.
If you'd like to contact Andy to discuss his design, he can be reached
at Andy.Redwood [ampersand]bigpond.com
After first building a 4m bi-wired set of Louis Muratori's variant of
the Jon Risch cross-connected speaker cable (for my "second"
system), I started to think about ways the cable could be improved. Then
the time came to replace the speaker cables in my main music system, so
I set to work!
First of all, with my active 3-way Maggie speakers, Net folklore has
it that it's beneficial to have very thick cables for the bass panels
- I know of some who uses 9awg cables here. As Louis's variant on the
CC cable uses foil strips cut from Solo/Alpha Core crossover inductors
in place of the standard coax braid, at first thought, making up "extra
low gauge" speaker cables appears to be problematic as the copper
foil is very thin (about 0.075mm by my calcs, if a 45mm wide strip is
12awg) and there is a limit as to how thick a foamed-teflon insulated,
solid-core central conductor can be.
However, with some help from Audio Asylum inmates, I was directed to
Belden 89292 which has a 14awg, solid-core central conductor with FFEP
dielectric. Of course, if you're happy to use stranded conductors, you
have more choice!
For the mid-panel and ribbon cables, I used Belden 1506a, which has a
22awg, solid-core annealed central conductor.
The beauty of Louis's variant, apart from making the whole cable out
of "solid-core" components, is that the width of the foil can
be adjusted to add more overall copper thickness. For instance, 14awg
has a cross-sectional area of 2.08mm sq. Add a 30mm wide strip of 0.075mm
foil and you end up with a total area of 4.29mm sq - which is just thicker
However, a 30mm wide strip will wrap round the foamed-teflon central
conductor about 1½ times so, to uphold "solid-core" principles
(adjacent conductors must be insulated from each other), you need to make
use of the thin plastic insulation strip which is used to separate the
layers in a foil inductor, to prevent the overlap from making contact
with the underneath layer of copper foil.
The second improvement which can be made to Louis's design is to do away
with the heatshrink! After all, the reason for the heatshrink is to:
1. hold the foil in place round the central conductor
2. stop air getting to the copper foil surface, and
3. electrically insulate the foil.
Instead of using heatshrink, I spiral-wrapped plumber's teflon tape tightly
around the foil strip - with about a 2/3rds overlap. The very thin foil
does roll easily around the central conductor's dielectric so all that's
needed is to keep the top layer of the overlap "tied down" tightly
and the teflon tape is certainly strong enough to do this. Thus:
· the teflon tape now holds the foil in place quite adequately
- possibly even tighter than the heatshrink!
· the foil is now covered with a couple of layers of teflon tape,
so it won't oxidise, and
· the foil surface is already electrically insulated,
so there is no need for heatshrink over the top. This must be
Then I put two layers of 1/8" polyester braid over the teflon. This
provides some additional "constriction" and I felt made the
cable look a bit more elegant. And the 2 layers, in conjunction with the
Teflon tape, will certainly ensure complete electrical insulation of the
copper foil surface.