Enchantment with voice range

I was under the impression that an enchanted objet could only use the range voice if it produced a sound of some kind.
Yet in the core book exemple p97-99 the character named Mari is enchanting "agony of the beast" in a wand at range voice so is that legal after all ?

I was always of the impression that if you had a device with a voice-ranged enchantment in it, then you had to speak for it to work (with the range being dependent upon your voice).

So, if you had a wand, you would need to say something when you activated the wand (likely the command word), with that utterance setting the range.

I see, that makes perfect sense...Thanks