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Posts: 6659
Joined: April 4, 2000
Contributor
Since: March 1, 1999
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While 8451 is OK, there are much better choices for use with XLR connectors, in terms of stock Belden cable, and part numbers that are readily available.
I copy Part 2 of my DIY cable note down below, where I call out various Belden part numbers.
Then, below that I list links to info on some DIY balanced cable assembly instructions that provide for some very high performance balanced XLR cables.
BTW, Neutrik seems to have changed their materials for their XLR connectors, I have reports that they are not as good as they used to be, so Duster's recommendation to use the Switchcraft is a good idea.
Part 2
DIY Interconnect Note, Part 2
--------------------
The best commercial twisted pair cable I know of is Belden 89207.
It has a tinned copper braid shield of 95% coverage (about the
max for a braided shield),
and duo=foil
one tinned copper 20 Ga. conductor
and one bare copper conductor, both with FEP Teflon insulation,
and a jacket of black tint Teflon (the cable looks really nice,
sort of a bronze overall effect). The capacitance between
conductors is 14 pF/ft. It is fairly stiff, but can
be bent to hold a shape fairly well. It is relatively free of
microphonics, but can generate noises when moved or handled,
depending on the impedance (low Z has negligible noise) of the
circuit.
2nd choice: Belden #89272 As above except shield coverage
is 93%, and both conductors are tinned copper, and jacket is
blue tint Teflon (looks kind of different!). Capacitance
between conductors is 16.9 pF/ft.
3rd choice: Belden #89999 As above except shield coverage
85%, and jacket is light beige FEP Teflon. Capacitance
between conductors is 18.9 pF/ft. This is more flexible than
the two above, but has less resistance to hum pickup due to
lower percentage of shield coverage. May have slightly less
handling noise in some applications. Is nominally intended
for use as a LAN cable, so it should be available from
distributors.
If flexibility is a big concern, then the best all-around
twisted pair cable I know of, with extremely low handling noise,
and better than average sonic performance is Belden #83393.
It has a special foil shield 100% (foil bonded to paper instead
of plastic for low handling noise) with a stranded tinned copper
shield drain wire, 20 Ga. stranded tinned copper insulated
with FEP Teflon and the overall pair wrapped in noise reducing
tape (a cloth tape impregnated with high resistance conductive
compound to eliminate triboelectric effects), and a bright
yellow silicone rubber jacket. Capacitance between conductors
is 22 pF/ft. It is fairly flexible, but has a slight spring to it,
sometimes called lay (or lack of it). The only other down side is
that the silicone rubber jacket is not very rugged physically.
It is prone to cut or split damage, as when a rack might get
rolled over it.
To this day, every sample of this cable I have given out for
evaluation by studio personnel or guitarists has not come back!
I quit "giving away" my personal stock years ago!
2nd Choice: Belden #83394 As above, except 22 Ga. conductors
and a red silicone rubber jacket. This jacket is proportionally
thinner than the 83393 yellow jacket and even more easily
damaged. OK if it is not run over or abraded.
3rd Choice: Belden #83396 As above, except four 22 Ga.
conductors allow cross-wiring ala Canare cables. Actually
performs better than 83394 (when cross-connected), but is
stiffer. Cross-connected it is fairly resistant to hum for a
foil shielded cable, however capacitance climbs to 40 pF/ft
with the cross-connection (also known as a star-quad hookup).
Not recommended for guitar use, OK for studio/hi-fi use.
Higher performance than above, but stiffer foil shielded
twisted pair:
Belden #89182 Like 89207, except foamed FEP Teflon
insulation, 22 Ga. conductors, and foil/polyester shield
w/drain wire. 28.9 pF/ft.
Belden #88761 As above, except red tint Teflon jacket,
35 pF/ft. This is the Teflon version of the classic 8761
used in studios world-wide for years as a cheap but good
twisted pair. The teflon insulation of the 88761 betters the
PP insulation of the 8761 sonically.
Belden #87761 As above except Red fluorocopolymer jacket.
Belden #82761 As above except Flamarrest jacket.
Belden #88641 Like 88761, except 24 Ga. conductors and
31 pF/ft.
Belden #82641 As above except Flamarrest jacket.
-Special Note-
CABLES WITH STEEL CONDUCTORS, COPPER COVERED STEEL, OR
SILVER PLATED COPPER COVERED STEEL, TENDED TO SOUND VERY
POOR. ALSO, CABLES INSULATED WITH PVC WERE FOUND TO BE
VERY POOR AS WELL. NOTE: COPPERWELD IS ANOTHER NAME FOR
COPPER COVERED STEEL.
Belden #'s for these types of cables are listed below.
If you are currently using one of these types of cables,
a very significant difference in audio performance can be
had by upgrading to one of the recommended types.
This list is for informational purposes only.
9456, 8421, 8417, 9454, 8416, 9239, 9223, 9224, 9264.
8446, 9686, 9685, 8788, 8434, 8413, 9399
8411, 8401, 8413, 8406, 9396, 9399, 8410, 8420.
9397, 9398, 1812A, 1813A.
This list is NOT all inclusive; if you have commercial
cables in use in your studio, home stereo, etc. check the
specs for that particular cable, WHATEVER BRAND IT MAY BE,
and make sure it does not have steel or PVC in it!
There are some who will take issue with the method used to
obtain this data (subjective listening tests), however,
none of the recommendations violates any of the commonly
accepted classical approaches to the quality of materials.
For instance, the recommendations for insulator materials
just happens to follow the ranking (more or less) of those
same materials for their dielectric constants, i.e.,
teflon has the lowest dielectric constant, and PVC has one
of the highest. By the same token, the conductor ranking
generally follows the ranking of conductivity.
So you can choose to follow these recommendations whether
you have one particular belief system or not, in either
case the data will be very likely to lead you towards
better performance of your audio system.
ADDENDUM
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 interconnects: Cut away and discard the
outer shield and jacket, twist a pair of foam insulated solid
conductors tightly around one another, place a piece of high grade
heatshrink over the two ends to keep the pair twisted, and slip
a copper braid over the pair for shielding. It is recommended that
this shield be hard grounded at one end only, typically the source end.
If you have heavy RFI or suspect interference problems, instead of
leaving the other end float, use a 0.01 uF ceramic capacitor to make
a connection between the shield and that end's ground.
Belden 1506A has a solid 20 gauge bare copper center with foamed
teflon insulation that can be used as the guts of a twisted pair.
This solid center contrasts with the stranded conductor on the 89259.
Cut away and discard the outer shield and jacket, twist the pair
of foam insulated solid conductors tightly around one another,
place a piece of high grade heatshrink over the two ends to keep
the pair twisted, and then take some of the center insulation, the
foamed teflon, and remove the copper conductor from the insulation.
The easiest method is to slit the insulation down one side, and
remove the copper wire. Now use this insulation only to fit in
next to the twisted pair in the crack between the spiraled tubes
of insulation, and then slip a copper braid over the whole assembly
for shielding. To dress out the outer braid, get some heatshrink
to cover the braid, or use some dippable/paintable PVC in the color
of your choice.
Digital Interconnects, 75 Ohm SP/DIF format using BNC or RCA
connectors.
Belden 89259 is 75 ohm impedance, and makes an excellent digital
interconnect. I recommend adding an additional shield of copper
braid over the teflon jacket, and hard grounding it at the source
end, and ground the other end of the braid via a 0.01 uF ceramic
disc capacitor. The additional shielding minimizes noise pickup.
Belden 1506A, a solid 20 gauge bare copper wire, with foamed teflon
insulation, and a Duofoil and 95% coverage tinned copper braid shield.
16.1 pF/foot, 75 ohms impedance. The additional shielding afforded
by the Duofoil seems to help minimize jitter due to noise pickup
by a digital interconnect. For the ultimate in shielding, add an
additional shield by slipping a copper braid over the cable jacket,
and hard grounding it at the source end, and ground the other end of
the braid via a 0.01 uF ceramic disc capacitor. NOT recommended for
analog audio use due to the fact that the Duofoil and tinned copper
shield do not make as good of a ground return path as the bare copper
shield in the 89259.
-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.
Newark can be found on the web at: http://www.newark.com/
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: $100
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: Info@Nemal.Com
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 89207, twisted pair, 100 foot spool
Newark: $120
Best Local Price: $80
Belden 89272, twisted pair, avaialble in 500 foot spool
Newark: $593
Best Local price: $399
Belden 1506A, used for digital coax 75 ohm, available in 500 foot spool
Newark: $399
Best Local Price: $303
Belden 82248, center only used for twisted pair interconnect or
multiple conductor speaker cable , available in 1,000 foot spool.
Newark: $743
Best Local Price: $550
Belden 89292, center used for speaker cable, available in 500 foot
spool.
Newark: $970
Best Local Price: $785
___
Possible Substitutions (These cables have not been listened to):
West Penn Wire (all available only in 1,000 foot spools)
25825, similar to Belden 82259, except solid center wire of 25 gauge,
bare copper with bare copper 95% coverage shield and foamed teflon
center insulation. 17 pF/foot. Jacket is a flame retardant low-smoke
PVC, similar to Belden's Flamearrest.
25815, similar to Belden 82259, except solid center wire of 20 gauge,
bare copper 95% coverage shield and foamed teflon center insulation.
Jacket is a flame retardant low-smoke PVC, similar to Belden's
Flamearrest. 16.5 pF/foot.
- - - - - - - - - - - - - - - - - -
American Insulated Wire Corp.
A55515, similar to Belden 89207
A55514, similar to Belden 89272
- - - - - - - - - - - - - - - - - -
Carol Wire and Cable, 500 foot spools
C8050, similar to Belden 89207
C8055, similar to Belden 89272
- - - - - - - - - - - - - - - - - -
Consolidated Wire and Cable
4798, similar to Belden 89207
- - - - - - - - - - - - - - - - -
Tech America 1-800-877-0072
Tech America will sell the cables they carry by the foot. If you
want to try some of the twisted pair interconnect, but don't want to
have to buy even a 100 foot spool, they carry several of Belden's
teflon insulated cables, and some have a bare copper center wire.
NOTE: THESE CABLES ARE FOR USE OF THE CENTER WIRE
AND INSULATION ONLY! THEY ARE NOT RECOMMENDED
FOR USE WITH THE INCLUDED BRAID, OR FOIL AND BRAID
SHIELD! In an audio coaxial cable, the shield DOES carry the
return current, and is a factor in the quality of materials issue.
Tech America part #910-1583, (Belden 82240), 64 cents a foot.
20 gauge solid bare copper center conductor in solid FEP teflon.
Insulation diameter 0.107"
part#910-1573, 86 cents a foot. (Is Belden 82248)
18 gauge solid bare copper in foamed teflon, insulation dia. .170"
part#910-1587, 90 cents a foot. (Is Belden 1506A)
20 gauge solid bare copper in foamed teflon, insulation dia. .135"
This one is the closest to the core of the Belden 89259, except
it has a solid center wire.
For a source of copper braid to place over the twisted pairs you
create: part#910-2314, 31 cents a foot, core diameter of 0.160"
and part# 910-1579, 76 cents a foot, core diameter of 0.285"
THESE ARE NOT FOR USE OF THE WHOLE CABLE, JUST
THE USE OF THE BRAID!
A 2 meter twisted pair interconnect made from the cores and
braid of these Tech America (Belden) cable part #'s would run
about $15 dollars, $4 for S&H, and the cost of the RCA plugs.
I do not recommend using the RS gold RCA plugs, due to very
poor sonic quality.
SOLDERING RCA's *********************
Soldering RCA Plugs
Each RCA plug is different in it's physical detials. For the
ground conection, some have large long lugs with strain reliefs
on the end, some are just a small tab, others have a small
nubbin to solder to. The large barrel type with the long
ground lugs are the best for DIY work.
Each one will dictate a method for termination.
For the small tabs and nubbins, comb the braid out, twist it
tightly into a lead that is gathered together as soon as
possible, then is formed towoard the open end of the cable.
Solder it into a common chunk, then cut-off the end, and trim
or cut the remainder to a chisle point that you then carefully
solder to the small lug or nubbin. The spacing has to work out
to meet or match the ground lug position once the center is
soldered into place, so space and size accordingly.
This technique will also work for the large lug style RCA's,
if the soldered shield stump is soldered to the inside of the
lug, without wrapping the shield wire around the lug. Be sure
to get a good connection, keep the shield stub against the lug
until it cools, and avoid any motion until it does cool.
For those with long lugs, and or strain relief tabs, it
sometimes helps to cut the strain relief tabs off, or even
the whole end of the lug. With most of the long lug types,
there is enough room to bend the lug down in an "S" shape to
allow the barrel to fit over the lug and shield soldered to it.
This necessitates a neat and tight soldering job on the lug.
NOTE: Some RCA plugs have a crimped ground lug, the plug and
ground lug are not one piece. For these, it is worth trying
to make a solder connection where you can get at the lug and
plug. Scape the area vigorously , then apply lots of heat and
feed a small amount of solder onto the area. Don't build it
up, or try to wick it in, or the barrel may not screw over
that area.
If you get a good solid solder joint that's slightly too big,
you can sand it or grind it down carefully to allow the barrel
to fit. Don't solder fill any grooves for the barrel to screw
on. I recommend this be done BEFORE soldering the cable to
the plug, and use pliers to hold the plug, or some other form
of insulated holder, as enough heat to allow the solder to melt
onto the plug heats the whole plug very hot.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
FYI, There is a companion note for DIY speaker cable, just e-mail
me or search Dejanews for a copy.
****************************************************************
Copyright Jon M. Risch 1997,1998, 1999 all rights reserved, except
transmission by USENET and like facilities granted. Any use or
inclusion in print or other media are specifically prohibited. The
informational content is not warrantied in any way or form, and any
use of said content are at the reader's own risk. The author shall
not be held responsible in any way for any damages or injuries
arising from the content of this post. Common safety practices
are encouraged at all times. Do not fold, spindle or mutilate.
****************************************************************
See:
Assembly of stock coax, and twisted pairs:
http://www.audioasylum.com/audio/cables/messages/91526.html
Assembly of twisted pair:
http://www.gingercable.com/ (chineese, but lots of pictures)
http://www.audioasylum.com/audio/cables/messages/99543.html
Assembly of balanced twisted pair:
http://www.audioasylum.com/audio/cables/messages/109148.html
Latest post:
http://www.audioasylum.com/audio/cables/messages/113781.html
Jon Risch
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