Chanting vs. Singing?
A. There is no difference. Cantare is Latin for "to sing." "By them are chanted songs that ne'er to mortal ears were granted" (LSB 679, Oh, How Blest are They, QED). The difference is in people's minds: they like singing; they don't like chanting. ('Not really sure why either... probably because chanting is "Catholick.")
This is why it's good to know that chanting is just singing. It's normal for the congregation to sing; it's normal for a cantor or choir to sing; it's normal for the pastor to sing also. Many pastors and laity don't find the debate about chanting worth having, especially if they're introducing it for the first time. I, for one, don't think I've ever spoken about chanting anything in the service. I do, however, sing most of the service. (E.g.: "Remember, catechumens, you're allowed to sing the Words of Institution just like I do every Sunday if it helps you remember them.") Our choir sings (chants) propers and sings hymn stanzas in alternation with the congregation.
2. Don't sing. Chant. There's a difference. For one, none of it should sound like this:
The most significant reason none of it should sound like this is that we want the words to be key. Think of chanting as a heightened form of speaking.
Singing can vary as much as opera varies from country twang varies from rap-metal screaming varies from those epic R&B songs at the end of 90s Disney movies. There are lots of different techniques, and we don't need to judge them here. We mostly need to avoid them. Singing is intended to highlight the talents of the singer and to amplify the words with the music. Musicians will use the verb "paint" to describe the way music can actually reflect the meaning of the words. The crassest possible example might be "sad-sounding" music with "sad" words. The voice, likewise, can do its part to sound mournful.
Chanting shouldn't do this. It doesn't intend to do it. The words are entirely in charge. That is true musically (especially if you are singing a Gregorian psalm tone or the sort you'll find in Lutheran Service Book), but the vocal technique should follow suit. Think of chanting as a heightened form of speaking.
Usually people heighten their speech with volume. We do want volume, but we want to get it like the trained singers do: by using our diaphragms well and projecting our sound. We don't want to yell, scratch, scream, croon, or bellow. It won't come from our shoulders or our throats or our noses, but our diaphragms (your abs, guys!). The volume is just support for the sound, it doesn't drive it. If you find yourself straining, you probably aren't chanting. (You might not be singing either.)
Chanting heightens our speech with the music itself. It is the natural voice set to pitches, without vibrato or other embellishments. Instead of merely speaking it in our normal voice, we speak it on one or more pitches. That's it. In fact, that is the best way to learn to chant (let's use the Lord's Prayer as an easy example, since we already know how to say it out loud, together with other people, and "in rhythm"):
1. Say the words out loud.
2. As you're saying them, be deliberate about it. Don't be over-dramatic or overtly slow in your speech, but say it with the care that it takes for speaking it in unison with a whole group of people. That's about the right pace.
3. If you're an animated speaker (imagine how a teacher would say it as he or she tries to get the whole class of kindergarteners to join in), tone that down a bit. Try to say your words almost in monotone, at least for the moment. It's closer to singing, actually.
4. Put it to a pitch. You can pick the pitch. Hum a note. Now just speak those words on that note, with the same deliberate pace and affectation which which you were saying it just now.
That's chanting. In the Church, when it comes to prayers, the Words of Institution, and readings, this is what we're doing. A large portion of psalm singing is done on a reciting tone—a single note—just like you've been doing. There is a 5th step, so to speak: now speak it with the same pace and rhythm you just sang it. If it sounds ridiculous, so did your chanting. If it sounds reasonable, deliberate, and clear, you've got the hang of it!
Remember, the words are in charge. In most forms of music, there is a rhythm and beat determined by the composer. In chant, the musicians themselves (or their director) determine the rhythm. And by "rhythm," I don't mean "and a one, and a two, and a..." I mean simply the natural "rhythm" of speech, as you just did it. The singers should not be slaves to the note values in chant. You will know that is happening when it begins to sound robotic. Just as every congregation finds their natural rhythm and pace for praying the Lord's Prayer together, groups of people chanting must find that comfortable rhythm and pace of corporate speaking—only in this case, that speaking is pitched.
You should notice how calm chanting is. It's not Fergie, certainly not Whitney Houston or opera. It really is speaking, but set to a pitch, and the words determine the rhythm and pace. This same calmness should continue even if there are more notes (e.g., the Words of Institution as you have them in LSB—probably the pastor's most song-like chant in the Divine Service).
If you are at all self-conscious about singing, this "calmness" of chanting has your back. So long as you remember that you're not doing anything beyond speaking on pitch, your normal voice will shine through, and the notes will not be the focus—good news for you, and good news for chanting, because that's the whole idea.
In conclusion, we want the simplest, clearest, plainest singing. That isn't to say talentless. There is room for skill in chanting, but it is the talent of a Japanese sushi chef rather than a line-style burrito blasting you with 20 flavors thrown in a tortilla and deep-fried. We aren't embellishing the text so much as highlighting its natural sound. The chanting of better singers will take advantage of their clear tone; the chanting of poorer singers will retain their natural gruffness (speaking, barely on a pitch); but both are simple and let the words drive it all. That's our whole aim, isn't it?
Let the Word of Christ dwell in you richly,
teaching and admonishing one another in all wisdom,
singing psalms and hymns and spiritual songs,
with thankfulness in your hearts to God (Colossians 3:16).