Cable Belden
AUDIO – CONTENT VS. QUALITY
In 1997, musician James Taylor, and his recording engineer Frank Filipetti, won a Grammy Award for best engineered album “Hourglass”. The big surprise was that this album was recorded in James Taylor’s living room. The explosion through the recording industry could be heard around the world. Now anyone could produce a ‘world class’ recording virtually anywhere.
Of course, the CD produced in the band’s garage is nothing new. It only proves that “content is king”. But perhaps we should add a corollary to that: “Content is king, and quality makes it sell.” In these days of MP3 players and low-bit rate downloads, it is amazing what low quality levels are acceptable to many listeners. But, even if we assume that 20% of the audience will listen regardless of the quality, that leaves a lot of audience who might also listen if the quality of the material, and the quality of its delivery, improved.
So quality still matters. It’s just that getting to that top level is now a lot easier (and a lot cheaper) than it used to be. Just note that condenser microphones, that a decade ago were rarely available below US$1,000 are now routinely available for US$199 or even less.
Are they the same? No, of course not. The question really is, can that $199 model be good enough for your project? Will it last on the road with abuse it might get? How well does it work outdoors as well as indoors? And a thousand similar questions. You might well end up back at the $1000 model just because you can’t afford to have a mic fail during your next recording or stage performance.
And this also applies to the cable between that microphone and the preamp or mixer. And don’t be confused: microphone cables, or any other cable, is just as technologically advanced as the device it is plugged into. And, like links in a chain, your signal quality is limited only by that weak link. And if that weak link is cable then, shame on you, because that’s the cheapest link to fix. You just have to know what to choose.
For analog microphones, there are really three basic choices: ruggedness, low noise, and performance. We’ll look at the first two of these factors and determine just what that cable would look like. The third, performance, will be the subject of a following column.
RUGGEDNESS
The most rugged microphone cables currently are made with rubber. These are very rare cables. You might think the cables you are currently using are made with rubber. It is very likely you would be wrong. There are formulations of PVC that look and feel like rubber, but are nowhere near as rugged. If you want to know for sure, just check with the manufacturer. You can also do a simple test. Get three feet of rubber-jacketed cable (such as Belden 8412) and tape three feet on a floor. Next to it tape three feet of any other cable you wish. Now find an office chair with metal wheels and go over these cables, back and forth, for a few minutes. If you know someone considerably heavier than you, have them go back and forth as well.
After this “torture test” un-tape the cables and look at them. Will you be surprised! The rubber cable is almost indestructible, while the PVC or other plastics, can get shredded quite easily.
LOW-NOISE
This can mean different things to different people. There is ‘shot noise’ also called ‘impact noise’ that is a common problem with guitar cables. However, that kind of noise is much rarer with professional balanced-line twisted-pair microphone cables. And the reason it is rare, is that the impedance of most professional microphones is very low, around 150 ohms, compared to guitars which are very high, up to 50,000 ohms.
More often, with mic cables, “noise” refers to EMI (electromagnetic interference) or RFI (radio frequency interference) which can easily work its way into the cable and interfere with the audio, or worse, work its way into the preamp, mixer, or console using the mic cable as a really nice “antenna”.
The way to reduce this effect is first, to run the twisted pair as a balanced line. This is what all professional audio devices already do. An explanation of balanced lines, with common-mode noise rejection, would take an entire column, and more. Goggle those terms out if you want to learn more. And one of the things you will find is that the ideal twisted pair has two wire very close to each other. (Wires close together make the noise on each wire as close to identical as possible.) This is one reason why we twist the two wires in a twisted pair, to keep them close together.
However, when you bend and flex this mic cable, the two wires in the twisted pair tend to untwist slightly. This makes them vulnerable to EMI and RFI, or to leak out the audio signals running on them to cables around them. There are two solutions to this problem.
The first solution is a very new solution and it is to stick the two wires together when they are being twisted. There is only one cable made like this, and that is Belden 1353A. It is, in fact, a single pair “data cable”, a single pair Category 5e computer cable. Now a computer cable installer would say this is crazy to have a “one-pair Category 5e data cable”, but now you understand it perfectly. If you can stick the two wires together, then no matter how you bend and flex the cable, they will stay right next to each other, and give you maximum noise rejection. In fact, the noise rejection is so good that this pair isn’t even shielded. Just stick the two wires into pins 2 and 3 inside the XLR microphone connector, and it will work just fine…with one exception. And that exception is microphones that are powered through the mic cable, “phantom powered” microphones. They need that shield to help deliver the power to run the microphone. Obviously, this unshielded cable won’t work there. But for all the self-powered microphones, dynamic, ribbon, and other designs, this cables would be an excellent choice.
The second way to reduce EMI and RFI is to have a special construction with not a single twisted pair, but four wires, something commonly called “starquad”. If you open up this cable, you will find that the four wires are in one spiral (not two twisted pairs). To use this cable, you must combine the two wires opposite each other. This then turns four wires into the two wires for your connector (pins 2 and 3 again). These starquad cables also have a shield that connects to pin 1.
How starquad gives you ultra-low-noise performance would take another entire column, but suffice it to say that the performance of this design, especially at EMI – low frequencies – is dramatic. It is especially good at 50 Hz power noise. So if you must hang microphones from a lighting grid, for instance, starquad would assure minimum 50 Hz pickup in each mic line. Just be sure that the mics themselves are resistant to 50 Hz interference.
About the Author
Steve Lampen has been with Belden for 19 years and currently is Multimedia Technology Manager and Product Line Manager for Entertainment Products. He has an FCC Lifetime General License (formerly an FCC First Phone License) and is a BICSI Registered Communications Distribution Designer. His latest book “The Audio-Video Cable Installer’s Pocket Guide” is published by McGraw-Hill.
Visit our web site www.beldenapac.com or email us info@beldenapac.com
Belden 1532A RG6 Burial Underground Coax Cable Gel Filled
|
|
Belden 9527 Cable 22ga/27 pair Shielded PVC 300V PLTC 100ft $55.00 |
|
|
Belden 1701A Plenum Cat5e Voice / Data Cable, 1000 Ft Reel 1701A-004-1000 ~STSI $439.48 |
|
|
Belden RF 400 Coax Cable RG8/U 50ohm 72 feet with one N type male connector $50.00 |
|
|
BELDEN E108998 CABLE W/BNC Plugs $38.69 |
|
|
Belden P/N 9L28016 Flat Ribbon Cable $27.30 |
|
|
Belden 1694A SDI/HDTV Digital Video Cable M/M, 20 Ft. $19.95 |
|
|
Belden 1694A SDI/HDTV Digital Video Cable M/M, 25 Ft. $24.95 |
|
|
Belden 1694A SDI/HDTV Digital Video Cable M/M, 30 Ft. $29.95 |
|
|
Belden 1694A SDI/HDTV Digital Video Cable M/M, 40 Ft. $33.95 |
|
|
Belden 8603 Cable 3 Wire NEW $25.00 |
|
|
Belden 8473 Cable $300.00 |
|
|
BELDEN 9259 RG 59/U FLEXIBLE COAX CABLE 9259 RG59U $87.99 |
|
|
Belden 9167 BROADBAND COAX, HEADEND/VIDEO CABLES BLK – RG59/U Type75OHM $250.00 |
|
|
1956 Belden Wire & Cable Bus Car Boat Train Forklift ad $8.95 |
|
|
Belden 9873 060100 Cable 20/3 Pairs AWG 20 Wire 100′ $79.00 |
|
|
Wurlitzer Seeburg Rock-ola Remote Volume Control cable – Belden 9730 6 conductor $1.25 |
|
|
Wurlitzer Seeburg Rock-ola Remote Volume Control cable – Belden 8485 5 conductor $1.15 |
|
|
Wurlitzer 3031 wallbox cable with 30 pin Jones plug – Belden 8749 – 21 feet (7m) $100.00 |
|
|
Belden 83559 002100 Cable 22/9C Shielded FEP Wire 50ft $228.00 |
|
|
Belden YV40650 RG6 Broadband Coax Cable RG 6 Series 6 Wire NIB Black 1000′ $78.00 |
|
|
Belden 8457 060500 Cable 22/12C Control Wire 500′ $410.00 |
|
|
Belden 8457 060 Cable 22/12C Control Wire 400′ $350.00 |
|
|
BELDEN 85105 5C 16AWG CABLE. TEFLZEL JACKET. 469′ ROLL $2,700.00 |
|
|
70 Feet Belden 8312 12 Pair Pr/ 1 Conductor 22 AWG Cable $189.99 |
|
|
246′ Belden 18AWG 3 Conductor Power Supply Cord 19503 B59250 Cable Wire $239.99 |
|
|
900′ Belden 9451001U1000 AWG 22 300V Shielded Cable $171.99 |
|
|
BELDEN 83709 9 C 16 AWG TEFLON PLENUM SHIELDED CABLE $395.00 |
|
|
Belden 9M28350 28ga 25 pair Shielded Cable 100′ $375.00 |
|
|
Belden 25ft BNC 4-Wire Video Cable Snake $9.99 |
|
|
1000FT BELDEN 8132 060 CHROME 4C 28AWG COMPUTER CABLE $649.95 |
|
|
250FT BELDEN 7125A ORANGE 7C 16AWG CONTROL CABLE $1,249.95 |
|
|
500FT BELDEN 7126AS ORANGE 9COND 16AWG CONTROL CABLE $3,999.95 |
|
|
Belden 8103 24ga 3 pair Shielded Computer Cable 1000′ $1,200.00 |
|
|
BELDEN 7731A RG11 SDI/HDTV COAX CABLE in ORANGE JACKET $275.00 |
|
|
BELDEN 7731A RG11 SDI/HDTV COAX CABLE in RED JACKET $275.00 |
|
|
Belden 9504 24ga 4 pair Shielded Computer Cable 1000′ $600.00 |
|
|
Belden 8723 4 Conductor Speaker Stereo Cable Wire $25.00 |
|
|
Belden1694A Coax Digital Video cable BNC M/M 3 Ft. $4.95 |
|
|
BELDEN WIRE&CABLE 8304 006 1000 #32 STR TFE LT.BLUE 1000′ $300.00 |
|
|
BELDEN WIRE&CABLE 1592A 009U1000 4 PR #24 PP FR PVC – 1M’-WHITE $334.00 |
|
|
BELDEN WIRE&CABLE 2650R2R08 RGB 5X MINI COAX 250′BLACK $429.00 |
|
|
BELDEN WIRE&CABLE 276005U01 14/4C HIGH STRND AUDIO 5C WHT $488.00 |
|
|
BELDEN WIRE&CABLE 8770060500 3 #18 LDPE FS PVC CHROME 500FT $440.00 |
|
|
BELDEN WIRE&CABLE 1694A0101000 RG6 COAX CABLE 1000′BLACK $669.00 |
|
|
BELDEN WIRE&CABLE 1701A 8771000 CAT5E+ 4PRB U/UTP CMP REEL 1000′ $584.00 |
|
|
BELDEN WIRE&CABLE DIW25732CUT500 CAT3,25PR U/UTP CMR CUT,500′ $729.00 |
|
|
BELDEN WIRE&CABLE 7913S5RBP BANANA PEEL 2XC5E/RG6QS 5C $541.00 |
|
|
BELDEN WIRE&CABLE 2650R5R08 RGB (5X MINI COAX) 5C BLACK $827.00 |
|
|
BELDEN WIRE&CABLE 83027 0101000 20 STR TFE BLK BLACK 1000′ $838.00 |
|
|
BELDEN WIRE&CABLE 9843 0601000 3 PR #24 PE SH PVC 1000′ $2,064.00 |
|
|
BELDEN WIRE&CABLE 9504 0601000 4 PR #24 PVC FS PVC CHROME 1000FT $964.00 |
|
|
BELDEN WIRE&CABLE 89730 008500 3 SH PR#24 FFEP SLF 500′ GRAY $3,143.00 |
|
|
BELDEN WIRE&CABLE 2851F1R04 16/2C CIR INT FPLR SHLD 1M WIRE OVERSTOCK $1,115.00 |
|
|
BELDEN WIRE&CABLE CT0002B51 COMPRESSION TOOL $115.00 |
|
|
BELDEN WIRE&CABLE 9116 0101000 18 GIFHDLDPE SH PVC BLK 1000′ $148.00 |
|
|
BELDEN WIRE&CABLE 260001R01 RG6QS 1M/RL WHITE $176.00 |
|
|
BELDEN WIRE&CABLE 270805U01 16/4C (65STRAND) 5C/BX WHITE $218.00 |
|
|
BELDEN WIRE&CABLE 2632R5U04 RG59 PRECSN VID COAX 5C RED $191.00 |
|
|
BELDEN WIRE&CABLE 5220UL002100 CABLE 16 GAUGE 2 CONNDUCTOR RISER RATED 1M $191.00 |
|
|
BELDEN WIRE&CABLE 275705U01 16/2C HIGH STRND AUDIO 5C WHT DIRECT BURIAL $144.00 |
|
|
BELDEN WIRE&CABLE 275705U40 16/2CHIGH STRND AUDIO 5C LIGTH PURPLE $144.00 |
|
|
BELDEN WIRE&CABLE 271005U01 1PR/14(42STRAND) 5C/BX WHITE $264.00 |
|
|
BELDEN WIRE&CABLE 275805U10 16/4C HIGH STRND AUDIO 5C PURPLE $264.00 |
|
|
BELDEN WIRE&CABLE 275805U01 16/4C HIGH STRND AUDIO 5C WHT $241.00 |
|
|
BELDEN WIRE&CABLE 791601U08 RG6QS 1M/BX BLACK $240.00 |
|
|
BELDEN WIRE&CABLE 734A1 008500 20 LDPE/FHDPE SH PVC $242.00 |
|
|
BELDEN WIRE&CABLE 275905U01 14/2C HIGH STRND AUDIO 5C WHT $290.00 |
|
|
BELDEN WIRE&CABLE ST0002B61 STRIP TOOL FOR 5B-2650R/2648R $73.00 |
|
|
BELDEN WIRE&CABLE 2920A1BGD BNC CONN F/MINI RGB 25AWG,10PK $54.00 |
|
|
BELDEN THOMAS & BETTS STRIP TOOL FOR RG59 RG6 RG7 COAX CABLE CST-596 CST596 NEW $19.99 |
|
|
Belden 430-7067-001 4307067001 CABLE $59.00 |
|
|
Belden 89913 Plenum Coax Cable RG8/U 50ohm 102 feet with N type male connectors $149.00 |
|
|
Belden 430-7066-001 4307066001 CABLE $39.00 |
|
|
Coaxial cable Ratchet Crimping Plier Belden1855A1865A1505A1505F1694A1694F179DT $18.99 |
|
|
Belden Digital Audio Cable AES/EBU – 110 Ohm – 4 feet $21.00 |
|
|
BELDEN-M MALE/FEMALE 19 PIN SOCKET CABLE $29.99 |
|
|
AMP 213932-3 M SERIES CONNECTORS WITH (4′) BELDEN-M 9159 CMG 19PR24 CABLE $12.99 |
|
|
BELDEN XCB1 D871000 MULTIPAIR CABLE CAT5 1PR X-CONN REE $6.50 |
|
|
Belden 8441 Audio/Control Cable 22awg 1000′ Black 8441-010-U1000 ~STSI $428.98 |
|
|
2500 Ft New Spool Belden 29501 Allen Bradley VFD Cable $999.99 |
|
|
BELDEN WIRE&CABLE HC2920A BNC CONNECTOR FOR MINI RBG $14.00 |
|
|
50 RG6 Snap-n-Seal compression connectors SNS1P6U coaxial TV F cable Belden T&B $15.99 |
|
|
Coax Cable RG108 Belden blu 103ft $65.00 |
|
|
Belden 9104 TNC 75 Ohm 15.3M GPS Antenna Coax RF Cable $35.00 |
|
|
USED Belden BNC cables Assorted Lengths lot of 40 / 75 Ohms $36.00 |
|
|
NEW AMPHENOL 31-71033 BNC 75OHM CABLE CONNECTOR PLUG COAX BELDEN 8214 CRIMP $3.29 |
|
|
NEW BELDEN RETRACTILE MICROPHONE CABLE 8490 23 AWG $9.99 |
|
|
Belden 8110 Cable PCM Link Lucent Alcatel ED7C827-31 G2 $29.12 |
|
|
Belden 9504 24ga 4 pair Shielded Computer Cable 450′ $250.00 |
|
|
Belden 7 Ft GigaFlex PS6+ Cat6 Cable AX350045 ~STSI $9.44 |
|
|
communication cable/Belden 7876A 500 FT Spool of Cable $300.00 |
|
|
Vintage Technical Handbook Belden Wire/Cable Guide 1981 $3.95 |
|
|
BELDEN – 6300UE 877 1000 – UN-SHLD MULTICOND CABLE 2 COND 18AWG 1000FT $99.00 |
|
|
CISCO ATM DS3 Duplex DS3/734A Belden coaxial cable 20FT $67.95 |
|
|
CISCO ATM DS3 Duplex DS3/734A Belden coaxial cable 25FT $52.95 |
|
|
Belden NAPA 728060 2/0 Battery Cable Lug NEW-NO BOX $17.00 |
|
|
Belden 728060 (Pack of 6) 8060 2/0 Battery Cable Lug $88.80 |
|
|
Belden # 82108 RG59 Plenum Cable 270 feet $42.00 |
|
|
BELDEN RG-8X MINI COAX CABLE 18 FOOT JUMPER 95%LOW LOSS $39.37 |
|
|
Belden 83269 Silver Coated Copper Covered Steel Cable 1100 ft. RG188A/U 50 OHM $1,100.00 |