Using your Aspen Lavalier Microphones with Plugin Power
Many professional Lavalier microphones (including Aspen Lav Mics) require Plugin Power to operate properly. Most consumer camcorders, DSLR cameras with microphone inputs, portable audio recorders, and even smartphones (i.e. iPhones) by default offer Plugin Power at the mic input port. Chances are if your device offers a dedicated mic input port and you've attached a Lav microphone, things went extremely smooth. Many people may never have to worry about 'Plugin Power' in general.
There are however some devices that allow you to enable / disable Plugin Power. For instance, on a Zoom H4n or Zoom H6 digital audio recorder your Lavalier microphone may not appear to be working when plugged into the 3.5mm (1/8th") mic input. Simply enter into the Zoom menu and enable Plugin Power.
Zoom H6 w/ Lav Mic plugged into 3.5mm : 1/8" mic input and enabling Plugin Power
Can I Adapt a 1/4" Plug to Lavalier Microphone?
If you've attempted to add an adapter to your Lav microphone so that you can plug it into a 1/4" input chances are it would not work (unless the Lav mic is self powered with it's own battery). The problem is that 1/4" does not offer the Plugin Power needed for the microphone to operate.
Stepping up your 3.5mm Mini Jack Lav Microphone to 1/4" may not work if the Lav mic requires Plugin Power
If you are having problems with a lavalier microphone connected to a low end camcorder or audio recorder, double check with the manufacturer to see if the product offers plugin power, or if there is a setting in the menu to enable plugin power.