First of all. Check the full
pronunciation guide from our
wiki's
Learning Dothraki pages. That's mostly what we know.
I've noticed in the show that sometimes it's pronounced more like cal... and sometimes like carl. I would hate for it to sound like my dogs name is Carl, I'm not too fond of that name.
English has such different dialects (and I, as a foreigner, confuse them all the time) that it's hard to discuss pronunciation based on just english examples. If you use a
rhotic accent, "carl" is a clear mispronunciation. But either way, how do you pronounce the vowel in "cal"? Looking at
english dialect chart the possibilities are myriad. If you sport a general american accent, to my ear that's severely off from supposed correct dothraki pronunciation.
Dothraki don't have phonetically different vowel lengths
1, so it's quite possible that there happens some less phonetic variation: stressed words and syllabes might have somewhat longer vowels, more like in that non-rhotic "carl".
The correct pronounciatio is [xal] where [x ] is the sound from the /ch/ is Bach, loch or l'chaim.
It's a funny question, if it's a good idea to use a presumably exotic phoneme in dog's name. People would generally pronounce it wrong, even the owners might get bored of a foreign sound and just move to an easier and more natural nick name. On the other hand animals are much better at learning to recognize sounds than sound sequences, so if the name would hold, it might be very recognizable for the dog.
1If a word has a pair of same vowels after each other, they are still pronounced separate. As far as I understand there is no glottal stop, diphtong or any such clear trick to mark the separation, so it is quite subtle, mostly just some stress on the latter vowel.