Sadly, most camcorders only offer a puny 1/8-inch microphone jack for attaching to the outside audio world. Mixers and professional microphones generally don't come with 1/8-inch connectors, so now what will you do? It's time to gather all your audio adapters, sit down with your equipment and come up with some creative alternatives.
Surveying the Landscape
Camcorders come in all different shapes, sizes and price ranges. Accordingly, these factors also influence their audio capabilities. Let's start at the top and work our way down. If you have the budget, there are cameras that offer professional XLR audio hookups — some even supply phantom power for condenser microphones. The Canon XL2 and Sony PD170 pretty much define this category. These are larger cameras with enough surface area for professional audio connectors. If you are one of the chosen few who own one of these jewels, congratulations, you need read no further — however, the rest of us poor slobs need other choices.
The bulk of camcorders that have an audio input sport a 1/8-inch stereo microphone jack. The matching plug looks exactly like the plug on your portable headphones. The tip connection carries the left signal, while the ring connection carries the right signal and the bottom portion — or sleeve connection — is for signal ground. The fact that this is a microphone input implies a few problems. First, commercially available non-video microphones do not have this type of plug, so you're going to need some adapters. Second, a mic-level signal's strength is a fraction of the level provided by a CD player or mixer. If you try to plug anything other than a microphone level signal into this jack, you'll hear nasty signal overload and distortion. It would be great if manufacturers offered an option to switch the input from microphone to line level – the Sony HDR-FX1 does just that, but don't expect this to become a trend.
Unfortunately, not every camcorder even comes with a microphone jack. This has more to do with market statistics and purchase price than a conspiracy against your creative muse. There's a price point where manufacturers assume the buyer is a casual user and will never need to input audio from another source. If you're in this situation, you have a couple of choices. The first, and most expensive, is to upgrade your camcorder. Yes, your bank account will take a hit, but you can relegate the old model to family use and dedicate the new camera to more lofty pursuits. In fact, if you use your new camcorder exclusively for a video business, you can even deduct it as a business expense. If a new camera isn't on the list, see the sidebar 'Audio Alternatives' for another option to squeeze the most from your audio dollar.
The Connected Life
You've got a camcorder with a mini microphone jack and a handheld mic with a professional XLR connector. How do you get these two to play together? Adapters, my friend. Starting at the camera, we need something with a mini 1/8-inch stereo plug. Another consideration is weight and length — we don't want six inches of junk poking out the side of our camera. Not only is it ugly, it's just waiting to get bumped and break the delicate connector inside your camera. One option is a 1/8-inch stereo-to-RCA cable. These are available in various lengths and are normally used to connect portable CD and MP3 players to home stereos. These have two RCA connectors on one end and a single 1/8-inch stereo connector on the other end. It's important to get the kind that connect RCA and 1/8-inch connectors via two short cables, rather than the smaller, rigid adapters that don't allow enough space to complete all of the necessary connections.
It would be nice if we could go directly from these RCA connectors to XLR, but we're still a few adapters away. It's easy to convert RCA plugs to 1/4-inch connectors with a simple adapter from your local electronics outlet. Quarter-inch connectors are more universal and many audio mixers use these for output, but we want to connect to a professional XLR microphone. Next on the adapter list is a double 1/4-inch female adapter known as a 'barrel' connector, or 'cigar plug,' due to its shape. Finally, we need a transformer adapter to convert a 1/4-inch plug to an XLR female — perfect for hooking up a professional microphone. If you buy two of everything after the cable, you can easily attach two separate microphones to your camera. This setup can't supply phantom power to a condenser microphone, but it works great with dynamic handheld mics and those with their own batteries on board.
In addition to hooking up microphones directly, you can use this adapter rig to connect to various audio mixers. Many small production mixers from Behringer, Mackie and others offer balanced XLR outputs on their back panel. For added flexibility, some of these outputs can switch between line level and microphone level — just make sure yours are switched to mic level, and you can send the output of the mixer to your camcorder's 1/8-inch stereo mic input. If you do this, you can use your audio mixer to open up a whole new world of audio sources. In addition to single or multiple microphones, you can blend audio from computers, CDs and MP3 players along with other sources, and then feed the mix directly to your camcorder. Using the pan controls, you can put all the microphones on the left channel and other sources on the right channel, or any combination you want.
Mix and Match
If all this adapting and converting has your head spinning, don't worry — there are easier, more convenient ways to accomplish the same thing. You'll pay for the convenience, but in many cases you'll have a very professional solution that will serve you for years. For instance, Markertek.com offers a simple cable that quickly converts an XLR-type output from mic or mixer to a 1/8-inch plug for your camera. If you need the ability to connect two mics or other sources, Beachtek and others offer custom audio adapters that mount to the bottom of your camera and convert XLR sources into a single 1/8-inch stereo cable. In addition, you'll gain volume controls and other options that make almost any audio hookup a simple task.
Regardless of how you do it, adapting audio for the mini microphone jack is an essential skill for the video shooter. Whether you're attaching microphones directly to a camera or going through a mixer, the added level of difficulty is worth it for the quality and flexibility your productions will gain.
Contributing Editor Hal Robertson is a digital media producer and technology consultant.
[Sidebar: Audio Alternatives]
For those who own camcorders without a microphone input, all is not lost. Big-budget productions often record the audio on a separate recorder, and then re-sync the audio and video in post-production. You can do the same thing with the audio adapters we've discussed and a portable MiniDisc recorder. With a little shopping, you can find one of these jewels on the street for under $200; just make sure it has a microphone jack on the side. The 1/8-inch mic input is the same as a camcorder's and you can record more than enough time on a single disc to match a DV tape. Back in the edit suite, you'll have to record the audio into the computer, then match your visuals to the audio on the timeline of your project. Using a slate with an audio clapper helps; that way, you can sync the audio with the visual of the clapper coming down. Tricky? Yes, but adversity often inspires creativity.