perhaps an unusual question..

[Mentat]

Agree with above and would head to YouTube and search for sounds (calling) of any species you like .

[Happy Frog]

I somehow missed this post. You mentioned a Wardian case which is what peeked my interest. I have seen these cases set-up with tropical plants and orchids and they really look good, like they would make a furniture quality dart frog enclosure. Some of the ones I've seen have dimensions close to that of a twenty gallon tall. I'm not sure how airtight they are but they are suppose to be a type of miniature greenhouse. At one time I actually thought of setting one up for dart frogs.

Go to Google, hit the images tab, and type in "Wardian Case" and you'll see what I mean.

My Leucs sound just like this;

Bumble Bee Dart Frogs Calling - YouTube