Design

(If you're not familiar with the linguistic terms above, velars (variations of k and "hard g") are formed when the back of the tongue meets the upper back of the throat. Alveolar consonants (n, d, t, "flap r," l) are formed when the tip of the tongue meets the alveolar ridge, on the roof of the mouth toward the front. Dental consonants (s, sh, j, ch, and similar consonants) involve friction between the tongue and the upper part of the top teeth. Bilabial (p, b, m) means two-lipped; the lips come together and are released. Vowels and glottal consonants (h and 'ng' in modern Korean) are formed in the throat.)

Korean consonants can be arranged into five groups based on depending on how the sound is produced within the mouth. Amazingly (to me, at least), each of these representative consonants is a simplified diagram showing the position of the organs of the mouth in forming those consonants. How cool is that?

Looking at the diagram, you should be able to see that there is an element common to all the consonants in a particular row.

The first consonant in each row is the simplest; this is a representative consonant for each group, and is the building block for the other characters in that group. These changes are largely systematic: adding a horizontal line to a simple stop consonant (sounds like the t/d or p/b pairs in English) forms the aspirated consonants (those made with extra air), doubling simple consonants gives us the "tense" consonants (pronounced with glottal tension, for which there is no real equivalent in English).

So, looking at the top row of the diagram, ㄱ( called 'kiuk') is a basic consonant. It sounds most like a hard 'g' in English (but has long been romanized as both 'g', 'k' and 'c', and so we have kimchi and gimchi, for example).
ㅋ(called 'kiut') adds an extra horizontal line, and gives us a more aspirated 'k' sound.
ㄲ (called 'ssang kiuk' where 'ssang' means double), the doubling of the basic consonant, gives us a slightly strangled (glottal tension added) 'k' sound, sometimes romanized 'kk'.

Looking at the diagram, you might notice that there are other triplets as well -- ㄷ ㅌ ㄸ (roughly and usually romanized d, t and dd), ㅂ ㅍ ㅃ (b, p and bb), ㅈ ㅊ ㅉ (j, ch and jj) -- and one doublet ㅅ ㅆ (s, ss), the regular and aspirated 's' sound.

It is important to notice, if you're serious about all of this, that there is no consistent differentiation between voiced and unvoiced consonants in Korea, as there is in English. Most English consonants appear in unvoiced/voiced pairs -- t/d, p/b, k/g, s/z, sh/zh, f/v and so on -- but in Korean, we have triplets -- basic, aspirated, and tense. Voicing does appear in Korean, but as a function of location -- for example, when a consonant appears between two vowel sounds in a syllable. This is, in my opinion at least, one of the root difficulties, almost universally ignored or misunderstood, in pronunciation interference for both Koreans learning English and English-speakers learning Korean. If you are a teacher, having a good understanding of this fact -- that aspiration and glottal tension are the fundamental differentiator in Korean consonants, with voicing not contributing to meaning, while the exact opposite is true in English (and voicing has a strong effect in English on syllable length) -- can be invaluable in helping your students understand how to clarify their pronunciation in a systematic way.

Notice that the five representative consonants to the right of the diagram, as well, showing the relevant part of the mouth involved. Ingeniously, each of these representative consonants is a kind of simplified schematic diagram showing the position of the mouth in forming those consonants. How cool is that?

One thing that we have to note before going on: I mentioned that Korean vowels are invariant in the last article, but that is not true for consonants. The good news, though, is that the changes, based on position within syllables, are quite consistent.

A Note On Romanization

Romanization is a somewhat complicated issue, unfortunately, and the revised romanization instituted by the Korean government in 2000 (not without criticism) to replace the McCune-Reischauer system of 1984 has not percolated in any systematic way through the country yet. The new system eschews use of diacritics and other non-alphabetic symbols (other than the hyphen, occasionally), and was intended in part to make it easier to type romanized Korean on computers. It is far from perfect, but is, in my opinion at least, an improvement. The major strike against it is that it essentially requires one to be familiar with the sounds and conventions of spoken Korean, and so, though useful for Korean speakers, is of limited use 'out of the box' to those who don't speak Korean.

The Korean government site has this to say about that

It is true that most Westerners hear "ㄱ, ㄷ, ㅂ, and ㅈ" as "k, t, p, and ch" when these consonants appear as the first letter in a word. But the problem is that "ㅋ, ㅌ, ㅍ, and ㅊ" also seem like "k, t, p, and ch" to the average Western ear as well, and the differences between each of these vowels are important in Korean. The Korean phonological opposition must be given first priority in a Romanization system designed for Korean, even if to foreign ears these differences are not easily recognized. In addition, when the differences between "ㄱ, ㄷ, ㅂ, and ㅈ" and "ㅋ, ㅌ, ㅍ, and ㅊ" are written with consistency, it makes non-native pronunciation of Korean more distinguishable to native speakers.

and I tend to agree with them.

English Equivalents

Here, then is a table showing rough equivalents for the consonant sounds in English,which you can compare with the diagram earlier:

back of the mouth:	g	k	gg
front of roof of the mouth:	n	d	t	dd
two-lipped:	m	b	p	bb
behind the teeth:	s	j	ch	ss	jj
in the throat:	ng	h

Putting It Together

OK, let's look at a couple of examples of putting together letters to make a syllable. There are consistent rules for making syllables, which we'll look at in Part 3, but for now, a few sounds to flex our Korean muscles.

Let's take ㄱ + ㅏ = 가.

ㄱsounds like a hard 'g'. ㅏ sounds (always) like 'ah' (this is not romanization, but phonetic rendering for clarity). So

ㄱ + ㅏ = 'ga' (which has in the past often been written 'ka'). It's the root of the verb 'to go'.

How about another?

ㅅ + ㅗ + ㄴ = 손

ㅅ sounds like a soft, lightly aspirated 's', ㅗ is always the monophthong 'oh' and ㄴ is exactly equivalent to 'n'.

ㅅ + ㅗ + ㄴ = 손 = 'sohn', romanized 'son'. It's the noun 'hand'.

At this point, I will leave you once again with this link to give you some audio help. Try the first few lessons again to get try and nail down your sounds. Don't worry if there are things you don't get yet, like the logic behind the position of characters within syllables -- I'll be covering them in future. At this point, though, with some practice, you should be able to sound out most (but not all, because we haven't talked about consonant positional variation yet) syllables you see.

As an exercise, try to sound out this:

안녕하세요?

When you've got it, you're able to greet someone, to say hello in mid-level formality, in Korean, the first thing everybody learns.

(Spoiler: it sounds like an yeong ha sae yo, with the syllables run together, following closely on one another.)

Stay tuned for Part 3, where we're going to start pulling everything together, and the real power of hangeul starts to shine.