“ch” like in Scottish English “loch” is closer to the “h” in “Ahmad” than the normal English “h"
It is indeed closer in terms of its place of articulation to English 'h' than either variant of the German 'ch' sound.
To my ears [ħ] sounds closer to [x] and [χ] than to [h] (even though the place of articulation is closer to [h]), but I'm sure it's different for people who (natively) speak a language with all three.