I was discussing reverb on vocals with a local musician whose mastered a few of his bands CD's.  He said that another musician told him the amount of reverb changes with the times.  "Sometimes, popular music uses a lot of reverb.  But today, very little is used."  If you apply it to a genre like pop or CCM, I might see a little of that.  It does seem the farther apart the years, the easier to see the difference.  The topic I see that needs to be raised is "how much reverb should I use in church worship songs here in 2009?"

Reverb has been called the "suck knob," the "talent knob," and "sandpaper" as it can be used to smooth out vocals.  But if you smooth something out too much, it becomes dangerous.  Take woodwork for example.  A freshly sanded piece of wood has a wonder feel to it.  Now take black ice as an example.  Ice that is so slick as soon as you step on it or drive on it, you lose control, is so slick, it’s dangerous.  Reverb should be like a sanded board - natural, smooth, and yet not all that noticeable.

Don't get me wrong, reverb isn't only used to "fix" poor vocalists.  That's just how it's most often attributed.

Reverb is heard all the time in a natural environment.  Playing guitar in a small room, I hear the reverb.  Talking with friends in a hallway, I hear reverb.  Anytime we are in a place with "good acoustics," we hear a natural reverb that sounds good.  Note this reverb is so natural to the environments, we don't notice it! 

Let's now put a microphone up close to a vocal, such as a typical dynamic cardioid microphone.  The natural reverb isn't being captured. 

A great place to start with reverb addition is adding back in the amount of natural reverb.  A simple tip when adding reverb back in, at first, is remember that if you can hear the reverb as a sound element in its own right, you have too much. 

Once you have captured the amount of natural reverb then you need to decide if/how to sculpt the remainder of the reverb.  Does the song call for more reverb?  How does the reverb match with other vocal effects you might layer in?  How does it sound in the overall mix?  There are no hard and fast rules for adding reverb but when you start by adding in natural reverb, as a guideline, it is a good starting point.

Backing vocals should be placed "in the background" of the lead singer so the lead singer stands out.  This can be done via lowering volume levels, EQ'ing so they don't stand out in the mix against the lead, and adding reverb so the backing singers blend together.  When using background singers, use more reverb on their vocals and less on the lead singer.

Reverb is a normal component of what we hear.  By adding it properly into the vocals, singer’s voices will sound more natural.