So eventually everyone should have wireless audio systems as part of their kit, but a decent set (on sale) can put you back $500 bucks only to capture audio from one subject. When you start placing a LAV mic on 2 subjects, then your costs immediately double up to $1,000 bucks. I recently helped on a project to record from 3 subjects having a conversation, and well let's just say that was over $2100 dollars worth of wireless audio equipment. I know most people can't afford to dive in to such expensive equipment right ways, so until you're at the point where you really need it, there are some excellent workarounds. Here are just two suggested ways to do this.
The easiest, most affordable, and straightforward way is to place a lav on your subject and run a stereo extension cord back to your camera. You can then monitor audio, adjust levels, and not have to worry about syncing audio in post.
10 Foot Extension for 3.5mm Stereo
If you can't have your talent tied down to a cord, you can always place an audio recorder with the talent. I use this technique, and I know many others who also do this with a Zoom H1. It's under $90 dollars and the audio quality is quite good. You can also use your iPhone as a portable audio recorder with many available sound recording apps. The drawback of course is that you can't monitor the audio, adjust levels on the fly, and have to sync the audio in post. The benefits are that you can afford to have multiple recorders for multiple subjects and don't have to worry about the possibility of wireless interference and drop-outs. Some even say that audio may even sound better than some wireless systems, as the recorders can capture the full sound.
Zoom H1 Portable Audio Recorder
So now that you have a few ideas on how to capture audio through a Lav Mic without a wireless audio system, the question now is what's a good lav for the job? Well in this video I run though a list of inexpensive microphones that all have 4+ Star Ratings on Amazon, and also introduce you to one of my new favorite under $50 dollars.
Here's how you can use your iPhone as a Portable Audio Recorder with the RODE REC App and an overview of the basic settings you should configure.
I like using DropBox to export my files, but you can also do this via USB and extract the file through iTunes. Here are the steps to do this.
Of course I can't forget about people who are using Android devices, so here's how you can use the popular sound recording application RECForge II from the Google Play Store.
If you're curious about what the sound quality is like when using a Samsung Galaxy S4 as a portable audio recorder, i've put this little demo together (below).
Here's a link to the various Lav Microphones mentioned for your reference. Although they have excellent ratings on Amazon, I found a few small things about each one that should be considered. If my opinion is worth anything, I would personally set my sights more towards the Rode SmartLav+ or the AspenMics Lavalier microphones.
Now keep in mind that the Rode SmartLav+ is latest version of this lav mic (don't buy the old SmartLav). Also the Rode SmartLav+ is designed as a direct TRRS Lavalier, so you'll need an optional adapter (found here) if you plan to use it with an audio recorder or if you want to connect this to your DSLR Camera. Combined with the adapter you're looking at about $95 dollars each Lav.
The Aspen HQ-S is the stereo version and will work directly with any camera or audio recorder. If you want to use the HQ-S with your iPhone, you'll need to purchase the kit that includes the TRRS adapter. The AspenMics are currently available at $45 dollars, so you can basically pick up two for the price of one Rode.