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DIY Speaker Cables, Cont'd  (Part 2)
 

High Performance DIY Speaker Cables from Commercial Wire:

It is possible to obtain high-end speaker cable performance
from commercially available wires/cables.  The information for
these home-made cable recipes was obtained through subjective
listening tests, and is based in part on earlier work done on
line-level interconnects.  Materials used in the recommended
wires/cables are of the highest quality with regard to conveying
an audio signal.  Some people may feel that the cables presented
here are wild overkill, I feel that they are barely adequate.
You have been warned!

Cable #1 - Highest Audio Performance

This is a somewhat difficult cable to assemble/solder, it is fairly
stiff, and the cost is somewhat high (minimum costs approx. $120
for two 24 ft. lengths, or approx. $2.50/ft).  But it sounds great,
and could be a contender against ANY retail high-end speaker
cable at any price!

This is a cross-connected dual-coaxial cable with foamed/solid
Teflon insulation, and bare copper conductors, using heat shrink
tubing with an inner layer of adhesive to bind the two individual
coaxes together.  Cross-connecting a pair of side-by-side coaxial
cables involves electrically connecting the center conductor of
one cable (cable A) to the shield braid of the other cable
(cable B), and the center conductor of the other cable (cable B)
to the shield braid of the one cable (cable A) at both ends.
Cross-connection is used to reduce the inductance to an absolute
minimum.  Merely paralleling the center wire and shield would
create two separated different polarity composite conductors with
an inductance much higher than the cross-connected pair.

The coaxial cable used is Belden #89259, the heat shrink either
SPC Technologies type PHD-032 1/2" adhesive-lined polyolefin
shrink tubing, or 3-M EPS-200 1/2" adhesive lined, flexible polyolefin heat
shrink tubing.
You do not have to use adhesive lined HS, with the speaker cable twisted,
it stays together a lot easier to begin with, and using more of the
non-adhesive HS will more than make up for the lack of adhesive.
The adhesive didn't really stick to the teflon jacket anyway, but it did
sort of encapsulate it.

Polyolefin type 3M typeVFP-876, 1/2" diameter, 50 feet for about $19
3M type FP-301 colors red and black, 5 foot section for $3.14, 1/4" for
color coding the cable ends, 1/2" for an IC or the whole cable.
The cable and heat shrink are available from
electronics distributors all across the country, including Newark
( http://www.newark.com/ ), DigiKey  ( http://www.digikey.com/ ),
Allied and others.

See Costs Section for details of the cable costs.
A 100 foot spool of the 89259, cut
in half twice it allows up to a pair of approx. 24 foot speaker
cables.  If you don't need all that length, cut the coaxial cables
appropriately shorter, and use the leftover 89259 for interconnects,
it makes very high quality line-level cables when used with a nice
teflon/gold-plated RCA plug.  The adhesive heat shrink tubing runs
around $44 for just barely enough to do the job (a package of 5 four
foot lengths, for a total of 20 feet), and it might be worth it to get
twice that to keep the cables together tightly.   If you use the thin wall
HS, then you could easily HS the entire cable length.

Use of Belden 82259 is not recommended for this
application due to it's use of a modified PVC jacket (Flamarrest)
which will be exposed to the cable's electric field due to the
cross-connection.  89259 has a teflon jacket which will not
compromise performance as the PVC might.

Precise wiring instructions follow.
The coaxial cables are stripped back 2.5 inches of the
outer jacket, the braid combed and dressed to one side, and the
center conductor cut off for 1", and then stripped off for 1".
The entire center conductor from the shield braid point is bent at
a right angle to then wrap the exposed center conductor wire around
the base of the adjacent cables braid.  The adjacent cables entire
center conductor is then bent toward the base of the original
cables dressed out shield braid, and the exposed center conductor
wrapped around the dressed braid.  Make sure that each
center/opposite braid pair of conductors does not touch or make
contact with the other pair.  Dress out the leads and color code
one coax braid/cable to be the hot side with a slice of heat shrink
(1/4") or using a red marker pen.  The two wrapped areas are now
soldered, using plenty of solder and heat.  Solder quickly, so as
to not melt the inner insulation very much.
(My favorite solder is Kester "44" in the 63/37% ratio)

Now, before completing the other end of the composite dual coaxial
cable, spiral the two cables around one another, being careful not
to twist them or stress the coax unduly.  Spiral them as tight and
neatly as you can.  Two spirals per foot is enough if it stays
tight, but do not use more than 4 complete spirals per foot.
Then slide as many of the sections of heat shrink tubing
as you decided to use over the unfinished end, and space out
accordingly.

Pre-form the dual cables in the shape/layout you desire, making
gradual bends, no sharp sudden radical angles, and make sure you
have each bend covered with a piece of heat shrink (or two, as
needed).  A minimum radius would be 6 inches.

Once the cable has been pre-formed to the shape for it to connect
to your power amp, and run to the speakers, carefully melt the
heatshrink onto the cable pair, keeping the pair as close and
snug as possible all throughout the length.  Heat shrink should
cover at least 1/3 of the distance along the cables, and be at
every bend.  With 3-4 inch length pieces, spaced every foot or so,
this will keep the cable pair from being able to move relative to
one another.  This is important to reduce any possible motor
action effects.

Also, I have found an inexpensive alternative to the adhesive
heatshrink or thin wall HS.
Take a clean cotton diaper, cut it into 1" strips, retaining the
full thickness of the diaper, and use PVC electrical tape to wrap
around the cotton strip wrapped arounf the coaxial cable pair.
Stretch the tape tightly, as you want the two cables held together
firmly for years.  This may require retaping over time, but it is
a lot cheaper than the adhesive heatshrink, and can be done closer
together due to the very low cost.  With the spiraling of the two
coaxes, even spacing the bonding wrap closer together than the
recommended spacing of 3-4" of heatshrink every foot still results
in a more flexible cable overall.  I would still recommend
heatshrink at either end, and for color coding purposes.

Once the cables have been heat shrinked or secured together,
the other end can be similarly terminated, and be sure that
the same coaxial cable is coded at this end as the first end.

Once completed, check for shorts with an ohmmeter.

You now have two flexible copper braid hookup leads that should
fit readily into most amplifier posts.  If you place a termination
on them, do it as well as you can: if a crimp, use the correct
tools, if you solder it, use plenty of heat and flux.  A good
crimp should NOT be soldered!  It could actually degrade the
connection.

An alternate method of bringing out the center wire is to poke the
outer braid with a sharp instrument like an ice pick where the
center core is to be angled sideways, and work an opening into
the braid, untill it is big enough to pull the center wire through,
this avoids having to comb the braid out, and re-rwist it together.
If you poke another hole in the braid that the center wire is
supposed to connect to, then the stranded center wire can be
run up through the middle of the braid.  This makes it easy to crimp
the center wire along with the braid, avoiding any soldering.

Crimping
A good crimp is going to perform better than even the very best
solder joint.  However, a marginal crimp is going to be worse.
In order to get a good crimp, one must use decent tools.

Klein #1005 crimping tool available for $18 is good, Greenlee 1921 for $24 also OK.
Parts Express carries the Klein for $25 as part number 362-110, and has a range of
crimpers from $6 to$40.
Radio Shack's part #64-404 at $6 is just barely passable, it only has an 8" handle, while the Klein
has a 9 1/2" handle, which allows much more leveragte to be applied to the crimp.

Soldering
My preferred solder for all but the most tweaky situations, is the Kester 63/37 euectic alloy,
with the "44" rosin core flux.  This is far and away one of the better solders out there.
Ersin Multicore in the same alloy is also a good choice.
Some folks prefer a more sophisticated alloy, but we are talking about very fine
distinctions now.  Kester 62/36/2, a 2% silver alloy is one of these (also should
get the "44" flux), and is also excellent, but takes more heat, and does have a
small plastic range.
Other very highly regarded solders are the Cardas Eutectic and the Wonder solder.

Measured specifications:  Equivalent to 13 1/2 Ga. wire,
or 0.0022 ohms per foot (13 ga. is .002 ohms/foot), capacitance
per foot approx. 49 pF/ft.  Due to the low capacitance, this is
excellent for longer speaker cable runs.  The extremely low
resistance and low capacitance do not come with a penalty of
high inductance, the inductance is very low at 0.067 uH/foot.
Only the ribbon cables are lower, and they have a much higher
capacitance.
 

(NOW CONSIDERED OBSOLETE DUE TO UNAVAILABILITY)
Speaker Cable #2
Another option is Belden's Vari-Twist cables.  They make a Teflon
insulated version, but unfortunately, it has silver plated copper
conductors.  Now I find it to sound a bit bright or "silvery",
but many who have heard it liked it very much, as the brightness
is very clean and has no trace of harshness.  Belden part #'s
8V28040/50/60 (40 wires, etc.), and they are expensive.
Measured parameters on these make them the lowest inductance (with
a very reasonable capacitance for the inductance) cables available,
every other pair has a reverse twist, and they are spaced apart on
the ribbon substrate.  Again, all the tan "ground" wires would be
connected together, and all the colored wires connected together
for the "hot" lead.

Measured specs:  20 pair - 255 pF/ft., less than .009uH/ft,
equivalent to 15 Ga. wire in resistance.
25 pair - 318 pF/ft., less than .007 uH/ft, equiv. to 14 Ga. wire
in resistance, 30 pair - 382 pF/ft., less than .006 uH/ft, equiv.
to 13 1/2 Ga. wire in resistance.

Note:  This is available only directly from Belden on special order,
and there is a minimum and a long wait for it to be manufactured.
Approx. cost last time I checked: $15-20/ft. depending on # of pairs.

Speaker Cable #3

Another option is to utilize plenum type Category 4 or 5 computer
wiring.  Readily available, and relatively inexpensive, this type
of wire comes in many different configurations.  The main things to
look for are in these Category 4 & 5 cables are:  FEP Teflon
insulation (plenum version), unshielded and bare copper conductors.
The shielded versions shouldn't be used, as well as the plain PVC
insulated versions or those with tinned wire.  Excellent cost per
foot for the performance.

The most common type has 4 pairs of 24 Ga. wires, when the hots and
grounds are paralleled, the 4 pairs of wire equal a 18 Ga. single pair
of wires.  Two pair cable is available, but I would not recommend
buying it for use, as the equivalent Ga. is only about 21 Ga., and
doubling or quadrupling up on it is not as tidy.  OK if you have a
spool laying around though and don't want to buy the 4 pair and up.

If you are going to buy it, this is the preferred part #:
Four pair 22 Ga. Belden #1557A, aprrox. $400 per 1,000 foot spool,
less resistance than 16 Ga. wire, equivalent to 13 Ga. when doubled
up (two four pair cables in parallel).  Runs approx. 72 pF/ft. for
a single 4 pair channel, and approx. 160 pF/ft for the double run
heat shrunk together.   NO LONGER AVAILABLE NEW.
Belden #1561A is an 8 pair version in one
jacket, more convenient than bonding two together, runs about
$820/1,000 feet.

Four pair 24 Ga. Belden part #'s:
1457A or B,  1585A or B,  1661A,  1669A
Mainstream CAT 5 cable.  The 1585A is available from Radio Shack
as their part #910-1603, for 31 cents a foot.  It may be available at a
few  RS stores, but is still avialble from their 1-800-THE-SHACK
phone order number.
Double up for an equivalent 15 Ga. wire, and a quadruple run is better
than 13 Ga.

Eight pair 24 Ga. Belden #1573A, roughly equivalent to 15 Ga. wire,
a double run is better than 12 Ga.  More convenient than two 4 pair
cables doubled up.

Twelve pair 24 Ga. Belden #1577A, roughly equivalent to 13 Ga.

Two pair 24 Ga. (if you have some laying around) Belden 1590A, 1657A
and 1665A.  Must be used in multiple pairings to get the effective
wire gauge up to a decent level.

Construction is straightforward, solder all the solid colored wires
together for ground, and solder all the striped wires together for
hot.  If doubling up on a cable, it is recommended that adhesive style
heatshrink of the appropriate diameter be used to lash the two/four
cable sets together (remember the recommended heat shrink is a 2:1
shrink ratio, do not get too small of a diameter, or it could split
when shrunk).  See construction details for Speaker Cable #1
re heatshrink usage.

I now recommend braiding the pairs ala the ChrisVH recipe, see:
http://members.xoom.com/cvenhaus/diycatfivecables.html
 Link to ChrisVH's page with CAT5 recipe

OR
http://www.geocities.com/venhaus1/diycatfivecables.html

Chris recommends a 27 pair basic cable, pulled abck to a 9 pair
for the HF's, and a 16 or 18 pair for the LF's.

27 pairs is equivalent to about 10 gauge, while 9 pairs is about
16 1/2 gauge, and 16/18 pairs is about 12 gauge.

The 27 pairs is a 3 braid of pairs, then another 3 braid of those,
then another 3 braid of the resulting braiding.

The 16 pair would be two 4 braids, and the 18 pair would first a
braid with two pairs treated as one, in a three braid, then another
three braid of the resulting braided cables.

WIth so many wire pairs, braided, there may be some issues
with total capacitance, and so it might be a good idea to be certain
that your amp or receiver can handle the capacitive loading
before constructing a long 27 pair cable.
Anything more than approx. 10-12 feet may be a problem for
some amps.

TO keep the capacitance down, especially if bi-wiring, you may
want to consider just a 16 or 18 pair version, this is still equivalent
to about 12 ga. total.

There is also the TNT recipes, but they have various problems,
such as the unavailability of the copper foil satellite cables in the
US, and with the use of raw CAT5 4 pair cable, the jacket
becomes a portion of the dielectric system, and again, in the US,
the CAT5 cables available all tend to have PVC jackets, while the
cable in the TNT article uses some other polymer that apparently
is not quite as bad for audio cables as PVC.

See:
http://www.tnt-audio.com/clinica/tweaks.html
for those interested.
There are a lot more audio tweaks at that site.



NEW!
Easy coaxial speaker cables from stock coax.

 Link to Part 3, Easy Coaxial Cables


Other than these, there are very few options for low-cost DIY high-
performance speaker wire.  If the thought of soldering all those
connections is a put off, then my personal opinion is that Kimber
Kable has the best low-cost speaker wire with the most universal
application to a wide diversity of stereo systems.

WARNING!  These cables all have higher capacitance than ordinary
zipcord, enough that some poorly designed amplifiers may oscillate
into these cables!  Most all modern amplifiers should not have any
problems, but there may be some exceptions.  Use at your own risk!

CAT5 CABLE INFO ADDENDUM

As far as I know, 1585A and B are still available from Belden distribs, as are 1669A and the 2 pair cable 1590A.  I keep the numbers listed in the note, so that anyone who has some of the CAT5 laying around, or scraps at work, can ID and use it.

Another source is Hosfelt Electronics Inc., 1-800-524-6464, or 740-264-6464, located at 2700 Sunset Blvd, Steubenville Ohio 43952

Their part numbers 36-431 for 4 pair 24 ga. at 29 cents a foot, is a FEP teflon insulated bare solid copper based cable in the CAT5 enhanced category, and should be suitable for DIY speaker cable.

Given the basics in my notes, i.e., be sure to look for bare copper, unsheilded, plenum/teflon construction, and you should be able to cross-referecne other brands or even find the latest data cables in the Belden catalog.

Newer Belden numbers for suitable CAT5 type cables, are:
1701A

Siameese construction (two 4 pair overall jacketed cables side by side) is used on:
1669A,
and new #'s
1653A
1703A

All these have PVC or Flamearrest jackets, and I recommend that the overall paired group of cables be
removed from the jackets and braided for maximum performance. If you just bundle the cables together, even if you use the pairings, the PVC overall jackets will compromise the sound somewhat.

ADDENDUM 2

Different Cable Configurations:

Belden 82248, is a foamed teflon insulated coaxial which can have
the 18 gauge solid bare copper center used for twisted pair
interconnect or multiple conductor speaker cable.

For multiple strand speaker wire, use in multiple pairs.  Twist the
pairs around in a neat pattern, and secure with heatshrink every foot
or less.  For a four wire (two pair) version, connect the two opposite
wires together for one polarity, and the other two for the other
polarity, or the classic star-quad wiring.  Four conductors will be
equivalent to 15 Ga. overall.  For more than two pairs, interleave the
plus and minus polarity to minimize inductance.

Belden 89292, is a foamed teflon insulated coaxial cable which
can have the 14 gauge solid bare copper center used for speaker
cable, as above.  Two pairs (four wires) will be equivalent to
11 Ga. overall.

Cable Costs and Availability:

The various Belden cables I recommend are not run of the mill Ham
radio coaxial cable.  In most cases, the local Belden distributor
will have to order a spool from Belden to get it for you.  In order
to give you a better idea of availablity, and costs, I have called
around and worked up some figures.  I will list both the price
Newark charges, and the lowest price from a local distributor.
I have found that Anixter is nationwide, and has some of the lowest
prices and an amazing depth of stock.  Many local Anixter
distributors in major metropolitan areas will cut to length, or
at least sell a leftover portion of a cut roll.

A list of Belden distributors can be found at:
http://www.belden.com/distributors/DISTLOC1.htm
and a list of distributors that will cut to length certain model
cables is at:  http://www.belden.com/products/rhtheatp.htm
This site is a listing of Belden recommended cables for use in video
and home theater installations.  These recommendations are not based
on listening tests, and do not match mine.

Belden 89259, My highest recommended multi-purpose audio cable,
coaxial.  Can be used for interconnects, speaker cable and digital
cables.  Available in 100 foot spools which only weigh 5 pounds
for minimal shipping charges.  Usually in stock or only a few
weeks from availability at Belden, so your distributor can usually
get it quickly.
Newark:  100 feet $142 plus S&H
Best Local Price: $0.92/foot cut to length (small local shop had
some leftover, not typically available at this price)
Typical Price, 100 foot spool: $108

An inexpensive source is:  (less than $100 for the 100 foot spool)
Nemal Electronics International
12240 N.E. 14th Avenue
North Miami, FL 33161
(800) 522-2253
Fax: (305) 895-8178
Email: [email protected]

Belden 82259, 89259 without the teflon jacket, OK for interconects,
not recommended for use as speaker cable.
Available only in 1000 foot spools
Newark: $797
Best Local Price: $580

Belden 1506A, used for digital coax 75 ohm, available in 500 foot spool
Newark:  $399
Best Local Price:  $30.



 Link to Part 3, Easy Coaxial Cables



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All website content Copyright Jon M. Risch, 1997 - 2002

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