Getting It Wired
by Carl Cornell
Real World 101
When a band on the road is not the mega headliner or is working with different sound systems every night, having a consistent rig that sets up, tears down and works with a minimum of effort can make the difference between a great show and another bummer gig.
The best way to make this happen is to be as self contained as possible. With the right assortment of cabling, multipin disconnects and direct boxes; the backline, drum kit and keyboard rigs can all be pre-wired. If the band has a multi-accessorized guitar player or two, that's another prime target for pre-wiring. If the fully pre-wired stage rig falls victim to the accountant's veto, many small time saving projects can be undertaken as the budget allows.
Probably the two most wire intensive setups are keyboard rigs and drum kits. For keyboards, having all the loose rack mount modules and processors mounted in a rack is a good beginning.
All of these units can be interconnected with audio and MIDI wiring and a bundled harness can be permanently plugged in at the rack and then extended out to connect the keyboards. The audio outputs can be wired through a unit such as the Whirlwind Multidirector - a 4-channel, 1 rack space Dl box.
Mic Wiring the Throne
Drum kit mic wiring is usually the most time consuming processes during any set change. If the kit is on a rolling riser, a small snake box with a multipin disconnect is the fastest way to plug in the drum mics. Whirlwind has even designed a drop snake designed specifically for this purpose, the DrumDrop .
The mics can be set in place, plugged into the DrumDrop and then connected to the PA with a simple twist of the multipin (such as a Whirlwind WI). Short of a multipin, even a simple bundled harness with all the mic cables taped together at the right lengths is a good time saver.
It must be said that for snakes in any active stage environment, it's worth the extra money for those heavy metal “proven military technology” multipin connectors. Although plastic connectors are often used because of the lower initial cost, they just don't hold up on the road and have a keen Murphy habit to get damaged just when you don't have time to be repairing a multipin connector on stage.
If good multipins aren't currently budgeted, a practical and cost-effective alternative can be an off-the-shelf drop snake. A low-profile stage box such as the MINI-6 or MINI-12 feeding back to a fanout at the larger stage box or console itself will provide clean wiring from the drum riser for rapid hookup at show time.
As with keyboard rigs, guitar and bass amplifiers can often be pre-wired with direct boxes built into the rack, so the only cables needing to be plugged in are the power and the one going to the instrument.
Don't Skimp Here
In many guitar systems, however, you will have more on the floor to deal with. Since low signal levels and high impedances are serious issues with guitar systems, we've found that the best sonic solution for long multi-line cord runs is not the use of snakes, but bundling together multiple lengths of premium low-capacitance, low-noise guitar cable such as Whirlwind's Accusonic + 1.
Guitars are just about your most sensitive signal output devices on stage, and the only place a high-quality snake isn't your best option for clean wire dress.
Guitar cords in general can account for a lot of your mid-show pain. Per the signal level and impedance issues mentioned above, they are prime sources of induced (beer signs, lighting dimmers, radio signals, etc.) and self-generated (microphonics, crackles & pops) noise. Plus, in a live performance they get worked more than the other cables and have to survive that on a nightly basis without getting progressively worse in the noise department before failing.
Keys for Guitar Cords That Sound Best & Survive
1) Braided Copper Shield.
Foil shields are significantly stiffer, making them annoying to performers connected to them and they deteriorate with constant flexing, making them fine for the studio or in a snake, but a time bomb for the guitarist on stage. Shields which are simply spiral wrapped will “spread” when you flex the cable, providing openings for those nasty outside sounds to jump into the guitar signal. The braid is a key issue.
2) Conductive Inner Wrap.
A conductive inner wrap under the shield will increase shielding and also reduce microphonics. This can be harder to spot, but becomes obvious when you smack the cable around. Some cables make a lot of noise when they get tapped. Good ones don't.
3) Low Capacitance.
This will matter with some guitar/pickup/amp combinations, and not with others. If your guitars all have onboard electronics, it shouldn't be an issue. For some of the classics, it's a big deal. So you don't have to think about it, lower capacitance is better. Try to stay under 50pf a foot if you can get the specs on the cable.
4) Strain Relief
A flexible molded boot protecting the last few inches of the cord before it enters the plug. This is a life-expectancy issue. Most cord fatigue takes place at the point where the nice flexible cable enters the hard inflexible plug.
Whirlwind uses a molded boot that tapers down onto the cord to progressively damp the flex. Lots of people use heat shrink, but it's stiffer. Some people don't use anything. When we (at Whirlwind) started using this type of boot on our Leader® cables, field failures (which were low) dropped a non-subtle 85%.
5) Multiple Copper Stranding
Look for multiple fine copper strands for the inner conductor. These give you flexibility while keeping resistance low. Esoteric audio people may tell you the extra surface area created by fine stranding also helps high frequencies due to “skin effect”. They'll probably add that you should use oxygen free” copper for a better sound (actually, “oxygen free” really means “less oxygen”, with different OF cables giving you different amounts of Oxygen Freeness). These intriguing possibilities aside, more fine strands for a given inner conductor gauge translates to more suppleness and greater life expectancy on stage.
Really Get It Together!
Done right, a set change is as easy as giving the sound company a set of numbered XLR tails (even if you are the sound company). At the sound board, prewiring of the effects rack(s) and a short insert snake or wire bundle are the path to a fast, predictable setup. If it will be the same board every night, you may have the luxury of using a multipin disconnect between your rack and the board.
If you are going to be hanging this rack off a different board every night, the most practical solution can be to have your insert snake's console fanout be TRS stereo phone plugs and carry a bag full of TRS to dual-mono phone adapters for the boards that have separate in and out jacks.
Finally, every sound tech needs a bag of black box goodies to get you through emergency situations that are not usually of your making. A good cable tester, miscellaneous adapters, in-line phase reversers, ground lifters and pads are indispensable. A few emergency 9V batteries never hurt either.
Carl Cornell has been the chief engineer at Whirlwind for over 20 years. He has also mixed performance audio professionally since discovering (much to his dismay) in 1968 that he had no future in front of the mic.
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