This one I love both because of the sound itself and how fun it is to make, and also because of the name of the IPA symbol. (Yes, IPA symbols have names!) It's called the hookup heng! How great is that! Another super-cool thing about this sound (and the symbol for it), is that it really only exists in one language—Swedish.
(My mother's native language is Swedish, so that's one more reason I love it!)
How's it made? It's a pretty complicated action, and so pretty complicated to describe, but you might get close if you squish the sides and tip of your tongue up quite tightly inside your upper teeth and protrude your lips out trumpet-like, bracing the lip corners and bringing the inner, wet surfaces of the upper and lower lips close together. (There are actually different versions of this is different dialects of Swedish, but this is how the Stockholm version—the one you hear here—is usually made.) You can hear it above in sju, the Swedish word for seven. Phonetically, the pronunciation you hear is [ɧʉ̟].
The alveolar lateral approximate is a lovely sound that's also fun to make. You may have heard it before or may even use it yourself if you speak Spanish or Italian. It's the sound spelled 'gl' in Italian, as in the word gli, and 'll,' as in pollo, in some varieties of Spanish (Andean, Paraguayan, some traditional speakers in Spain).
To make it, you bring the middle of your tongue—not the tip—up to the roof of your mouth and make an 'l' like sound, letting the air flow around the sides of the tongue.
Who doesn't love clicks? This is the one horse riders usually use to say 'get moving!' to their steeds. It's one of several different click sounds that can be heard in Khoisan and some Bantu languages. It's even in the name of one of them, Xhosa—the 'xh' indicates an aspirated lateral click—you can hear the puff of air that follows the click before the vowel sound kicks in.
Here's a cool vowel sound. It's called a close back unrounded vowel, which means the back of the tongue is arched up very high towards the soft palate (the tongue tip is down behind the bottom teeth, as for all vowel sounds). This is the same tongue position as for an [u] sound, as in the word goose or true, as they
might be pronounced by an old-fashioned Shakespearean actor. ;) The only difference is lip-rounding. The lips are rounded strongly forwards for [u], but completely relaxed or even spreading a bit for [ɯ]. This fun sound doesn't really exist in English or most European languages, but can be heard in Mandarin,Japanese, Vietnamese, and Estonian, among others. To try it yourself, make a long, very back [u]. Keep your tongue in place, and slowly unround your lips. There you go!
In Tlingit, Navajo, Cherokee, Icelandic, and Klingon (!), there's a fascinating sound called a voiceless alveolar lateral affricate. (Tlingit is a language spoken by an indigenous people of Southwestern Alaska and Northwestern Canada.) An affricate is a two-part sound composed of a stop and a fricative. English has two
affricates: the 'ch' sound [t͡ʃ] in cheese, and the 'soft g' sound [d͡ʒ] in giraffe. If you break these sounds down, you should discover that they're both composed of two parts. [t͡ʃ] is a [t] sound plus an 'sh' [ʃ] sound. This sound is similar, except instead of the [ʃ], the [t] releases into an alveolar lateral fricative [ɬ], which is like an ordinary English [l] sound, except hissy and without any voicing (meaning the vocal folds aren't vibrating. (This sound is sometimes called a 'lateral lisp' when heard in English speakers as a version of an [s] sound.) You can hear the sound above at the start of the Tlingit word for moth, tleiloo.