The Whirlwind IsoPod & PodDI allow you to plug consumer audio gear into one channel of a mixer. They sum the unbalanced audio from stereo to mono, and send out a balanced signal via XLR.
If you want to keep your signal in stereo, be sure to check out the Whirlwind PCDI & PSUSB video here: https://www.youtube.com/watch?v=dJMMudeVwtg
This video will show you how to properly hook unbalanced stereo signals into a mixing console. The PCUSB is a simple Digital Audio Converter for plugging a computer directly into a mixer.
Shoutout to Primo Sol for supplying the backing track!
The Whirlwind Little IMP is an inline impedance matching transformer used for plugging low impedance microphones with an XLR cable into high impedance 1/4" mic jacks. It can even be used to plug a microphone into a guitar amplifier, although this is not recommended if you're looking for quality sound.