"Mäd" is pronounced as the English "mad".
I would prounce the CH in "chen" just like the CH in
Charles. CH is pronounced with this soft sound before a soft vowel.
In the beginning and before a hard vowel it is pronouned as K (as in Chaos), apart from loanwords like "champagne". At the end of or in the middle before a hard vowel, there is this special harsh sound, as in Bach, rauchen. Similar sounds like this "ach-laut" are in Spanish, Arabic, Chinese etc. It makes you thirsty to say these sounds, when you are not used to it ;)
"You sought a flower and found a fruit. You sought a spring and found a sea. You sought a woman and found a soul. You are disappointed."
"It does not become me to make myself smaller than I am." (
Edith Södergran 1891-1923)