Question

x Not found in Modern English. Like Scottish Loch Ness and German Bach. It is the pronunciation of Spanish j and g (before e/i) in most dialects : jefe, José, general, gitano (a few dialects, such as Caribbean Spanish, pronounce them as [h] instead). In parts of Puerto Rico the rolled r is pronounced this way: Puerto Rico [pueltoxiko].

Accepted Answer

Voiceless Velar Fricative http://en.wikipedia.org/wiki/Voiceless_velar_fricative

Symbol	x
Name	Voiceless Velar Fricative
Notes	Not found in Modern English. Like Scottish Loch Ness and German Bach. It is the pronunciation of Spanish j and g (before e/i) in most dialects : jefe, José, general, gitano (a few dialects, such as Caribbean Spanish, pronounce them as [h] instead). In parts of Puerto Rico the rolled r is pronounced this way: Puerto Rico [pueltoxiko].
Ref	http://en.wikipedia.org/wiki/Voiceless_velar_fricative

Velar Fricative Ch Puerto Rico X Voiceless Found