Is Acoustic Treatment Necessary for Voice Overs?
Yes! But there's no need to be scared of it.
Sound is air waves moving at different speeds.
Much as the same as yelling into a pillow muffles sound, studio acoustic treatment performs a similar function. The point of studio acoustics is to control the sound created in the room. For voice over this means to ensure the sound only comes from your talent's mouth, NOT from sounds reflected from within the studio. You can always add on effects like reverberation and echo in post, but it's impossible to remove unwanted artifacts if the audio was recorded in an "echoey" room.
Foam and soft surfaces absorb sound
If you're just starting out in voice over, you don't need a professionally treated studio to get started, but pay attention to the room you're recording in. Smaller rooms are better because you have greater control of the sound.
Walk in wardrobes are ideal as they're small and the clothes around you will absorb a lot of the echo/stray sounds.
If you don't have access to a walk in wardrobe, try doing what i did which was standing in-between 2 mattresses with a blanket draped over top (like a pillow fort!) just don't forget to come out for air every 10 minutes!
Anything you can do to prevent sound from bouncing around the room will help improve your voice over quality. Check out my video below for a demonstration of an ideal recording set up.