Working in live sound is an exciting and rewarding business. It’s very fast paced and you must problem-solve on the fly. Having the tools to handle anything is essential for a smooth and professional event. Here are some useful tools I have found to be indispensable, as an audio engineer and system designer.
Hearing Protection
The art and science of audio engineering relies solely on your hearing, and hearing protection is a must. If you have ever gone to a concert and heard “ringing” afterwards, you have suffered damage to your hearing. Over time, this ringing will develop into tinnitus, which is the constant ringing. It’s possible that it may subside, but for some, it is constant and maddening. As an engineer, you may EQ and run your system so that you won’t have ringing in your ears at the end of the night (good on you!); however, you could still be doing damage. The recommended exposure levels start around 85 dB with a safe listening time of 8 hours. As the dB level increase, the listening time decreases exponentially.
88 dB – 4 hours
91 dB – 2 hours
100 dB – 15 minutes
It’s necessary to protect your hearing. The best options are custom-made attenuators, which are molded to the shape of your ear by an audiologist and include a full-range frequency filter with -15 to -25 dB attenuation. They allow the entire frequency range through, while keeping levels tolerable. You can wear them while engineering, with reasonable results (I will take mine out for critical mixing and put them back in for regular monitoring). If you find yourself without custom attenuators, there are universal options that work well and are reasonably comfortable. I’m a fan of the Etymotic Research ER20XS.
An SPL meter is another essential tool because it not only allows you to take dB readings of the room, it can also be indispensable when using a multi-speaker setup to verify if your full-range speakers are in the same range as your subwoofers. An inexpensive option is the Nady DSM-1X, which offers a range of 30 to 130 dB and includes A and C frequency weighting.
Cables and Adapters
Cables will get damaged and will eventually fail over time. Always carry extra cables. A large portion of my sound system is self-powered, so I’m using mainly XLR cables. I started with 100' cables, but quickly learned that unless it is a permanent install, you should opt for 50' cables because they are much easier to coil and that saves time during setup and breakdown. Quad core offer the best quality and the best noise rejection; however, they can be expensive. Another useful tip is to buy your XLR cables in different lengths with different colors. For instance, all my 15' cables are blue, my 25' cables are brown, and the 50' cables are black. You will inevitably encounter gear with ¼" inputs and outputs, so I keep several short ¼" to XLRF and ¼" to XLRM cables on hand. Adapters will work too, but I’ve found on some ¼" gear, the jacks are too close together and adapters won’t fit. B&H has a fantastic cable finder that will help you to locate just about any cable you can think of.
Artists show up and ask, “Do you have a ____ cable?” My response is always, no, but I can make one! I’ve been asked for RCA to ¼", 1/8” to 2x ¼", RCA to XLR, ¼" stereo to 2x ¼" mono, and any other strange permutation you can think of. Having an adapter kit has saved the day on several occasions. You can piece together a kit à la carte, or dive right into a complete kit, which can offer a turnkey comprehensive solution that comes in its own case. I’m working with a lot of electronic acts and DJs, and most things are in stereo, so I recommend to have at least four of each type of adapter. The most common adapters I’m asked to provide include 1/8 to ¼" (headphone adapters), ¼" to RCA (RCA to ¼"), and 1/8" stereo to RCA.
I’ve also had people helping run cables during setup only to find that they’ve run the cable in reverse, so the female end (typically output) winds up at an input. On these occasions, a turnaround adapter will save you a load of time and headache. You can find these with just about any type of connector including RCA and ¼".
Audio Problem Solvers and DI Boxes
B&H has a dedicated Audio Problem Solvers section under the Pro Audio menu. There are seven categories, including In-Line Mic Accessories, Level Matching Transformers, Hum Eliminators, Pads and Mute Switches, Splitters & Combiners, Phantom Power Supplies, and Cable Testers and Tone Generators. It’s worth perusing each category because you might find items you’ve never considered that might help you.
Products that I highly recommend include audio and electrical hum eliminators. I run into many venues that don’t have properly grounded power and, thus, introduce an annoying 60 Hz cycle hum into the audio signal path. I carry a few RapcoHorizon ISOBLOX, which offer 600 Ohm 1:1 inline isolation and, more often than not, will do the trick. Sometimes, the noise from the electrical system can be overpowering and even the isolator has a hard time removing it. One trick is to use an electrical ground lift, which removes the grounding pin from a 3-prong power cord. This will work, but you are in danger of destroying equipment if there is a power surge. A better option is to try an electrical ground lift like the Ebtech Hum X, which safely removes unwanted voltage and current in the ground line that cause ground loop hum, while simultaneously maintaining a solid, safe ground.
Sometimes I’ll get an overzealous DJ or artist who can’t seem to keep their levels in check. They’ll be producing more than +24 dB, which will often clip the preamps in my live mixing console. On these rare occasions, I’ll place an inline pad with -15 dB of attenuation. There are a variety of attenuators with different dB attenuations, from -10 to -50 dB.
Another highly useful tool is a DI or Direct Injection box, which is designed to interface unbalanced stereo line sources with professional, balanced low-impedance equipment. Many have ¼", RCA, and 1/8" inputs and feature a 20-dB pad and ground lift. These are standard in most live applications. You can find them in passive or active versions, and some even have Jensen transformers.
For troubleshooting, I highly recommend Whirlwind products. I’ve tried a variety of less expensive units, but inevitably they break and usually at the worst possible moment. The MCT7 Multi Connector Cable Tester can test a variety of cables, including SpeakON NL4, RCA, BNC, MIDI, 1/8", ¼", and XLR. The unit is battery powered and highly useful in the field. The Whirlwind Qbox is a must-have in the field and includes a microphone, speaker, test tone generator, and a headphone output. The unit can generate a signal or monitor an incoming signal, which is imperative when troubleshooting.
There’s so much to cover regarding piecing together a survival kit. Hopefully, this should get you started. If you have questions or need advice, visit us online or drop by the B&H SuperStore.
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