that voice-over voice??

First you gotta have the voice. You can't fake it. To some extent you can learn it, but there are "naturals" who are born with it. After that it's the mic and how you use it. A lot of VO stuff is done with an Electrovoice RE-20. They are not susceptible to the typical cardioid microphone proximity effect, which boosts the low end as you get closer to it. Therefore, the talent can crowd the mic, causing it to pick up a "super-real" amount of detail in the audio, without getting boomy. There's more, of course, and probably other mics with similar properties, but that's my take. I engineered voiceovers for years.

davdud101
Was listening to vocal demos of popular commercial/radio narrators/voice-over artists and it had me wondering... How do they get that SOUND? To me it captures all the natural nuances of the humans voice in a snappy, somewhat bright, but bold-and-bassy fashion.
Seems to be a work of EQ'ing and mic choice as well as technique, but it has me really wondering!

You are so wrong. Ever heard the term get it right at the source! Well with voice over artists this is just so true.  I  have done a ton of voice over recording and it never seems to amaze me. Sometimes this small framed meek person comes in and as soon as they open their mouths it is like OMG!!!! You could record a great VO artist with an SM58 6 inches away and you will still get that sound. (and use no processing) Even their speaking voice is different to their VO voice 
 
You can learn a lot about VO technique from a specialist teacher and most of them have done that too. I even started it myself. But you have to have the voice to start with.  What you can learn is things like how you start a sentence at slower pitch and rise up and then as you coming to the end of a sentence you are back down again.
 
(Bit like a Jazz solo. Ease into it, reach a peak and taper off)
 
Also the letters at the ends of words have to be pronounced. The t's and s's at the ends of words. Great VO artists have excellent diction too.
 
Here in Australia we have a guy called John Laws. He has just got the deepest voice on the planet. It records so well. The deeper the voice the more powerful it becomes and the more believable it is too. He gets more VO work than anyone I know just because he was born with that voice.  Many women are born with a fantastic voice too. 
 
The smart ones know it and take advantage of getting probably one of the highest hourly rates in the whole industry. Similar to a dentist or lawyer!
 
It is a gift. You either have it or you don't. 

Although I have no experience recording voiceovers, I reflexively try to identify microphones any time I see them in a photo or video. What do they use on mandolins at the Grand Ol' Opry? (KSM32). What about voice actors on South Park? (U87). Singers on The Voice? (AKG handheld condensers). Metallica vocals? (SM-55). Full orchestras? (Schoeps or Neumann SDCs).
 
I've noticed that the RE-20 does seem to be very common for voiceovers, as well as with podcasters. In years gone by, it was a favorite of radio DJs (remember those?), so you'd hear it a lot in radio commercials. The newer RE-27 is also very popular. Here's a comparison of the two: