Belden 1813 Microphone Cable

Belden 1813 Microphone Cable

Belden 1813A is a two-conductor, 24 AWG balanced audio cable for microphones and general analogue audio interconnects, published by Belden in its microphone cable range. One twisted pair of high-conductivity bare copper conductors carries the signal, a bare copper spiral shield with 90 percent coverage surrounds the pair, and PVC insulation and a PVC jacket complete the construction. Belden lists the cable for multichannel interconnect between audio equipment such as microphones, speakers, amplifiers, and mixing consoles, and for live events, studio sound, and analogue audio generally. It is supplied as bulk cable for termination into the connectors your system uses.

Key features

• Two conductors, one pair, 24 AWG high-conductivity bare copper
• Fine 27×38 stranding for a flexible conductor
• Bare copper spiral serve shield with 90 percent coverage
• PVC insulation with blue and red conductor colour code
• Matte PVC jacket, 0.236 in (about 6.0 mm) overall diameter
• Nominal capacitance of 33 pF/ft conductor to conductor
• Belden part 1813A, from the manufacturer’s microphone cable range

Construction in context

Every element of the 1813A construction serves the balanced audio job it was designed for. The twisted pair is the basis of balanced working: interference picked up equally by both conductors is rejected by the balanced input at the receiving end. The fine 27×38 stranding keeps each 24 AWG conductor flexible, so the cable dresses neatly on stage, coils without fighting back, and tolerates the repeated handling that microphone leads live with. Around the pair, the spiral serve shield adds a second line of defence against hum and buzz from lighting dimmers, power cables, and other interference sources that share space with audio runs, while its 90 percent coverage keeps the cable supple in a way a full braid at this size would not. The published capacitance figures, 33 pF/ft between conductors and 61 pF/ft from conductor to shield, are the numbers engineers use when working out how long a run a given source can drive without dulling the top end.

Where 1813A is used

This is the class of cable found wherever balanced analogue audio is wired seriously: microphone leads in studios and on stage, interconnects between consoles, outboard equipment, amplifiers, and powered loudspeakers, and multichannel installations in houses of worship, auditoriums, and corporate spaces. Because it is bulk cable, the installer chooses the length and the connectors, which suits fixed installations pulled through conduit and trunking as much as it suits a workshop making up a set of matched microphone cables. Conductor DCR is published at 22.8 ohms per 1000 ft, with shield DCR of 11.6 ohms per 1000 ft, giving system designers the figures they need for longer runs.

Termination and handling

Terminate 1813A with the connectors your equipment requires, observing the blue and red conductor colour code consistently so polarity is maintained across every cable in the system. Keep solder joints clean and strain-relieved, since most field failures happen at the connector rather than along the cable. Route audio runs away from mains cabling where practical, cross power cables at right angles when they must meet, and avoid crushing the jacket under flight-case lids or chair legs. Coil finished leads loosely rather than wrapping them tightly around an elbow, and the fine-stranded, flexible construction will reward that care with a long working life.

Belden 1813A is a manufacturer-specified, balanced microphone and audio interconnect cable with published electrical figures, a flexible fine-stranded pair, and 90 percent spiral shielding, ready to be made up into leads or installed as part of a permanent audio system.