When they sound off, it is a true audio/visual experience.
1	When	when	ADV	WRB	PronType=Int	3	advmod	3:advmod	_
2	they	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	3	nsubj	3:nsubj	_
3	sound	sound	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	13	advcl	13:advcl	_
4	off	off	ADP	RP	_	3	compound:prt	3:compound:prt	SpaceAfter=No
5	,	,	PUNCT	,	_	13	punct	13:punct	_
6	it	it	PRON	PRP	Case=Nom|Gender=Neut|Number=Sing|Person=3|PronType=Prs	13	expl	13:expl	_
7	is	be	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	13	cop	13:cop	_
8	a	a	DET	DT	Definite=Ind|PronType=Art	13	det	13:det	_
9	true	true	ADJ	JJ	Degree=Pos	13	amod	13:amod	_
10	audio	audio	ADJ	JJ	Degree=Pos	12	amod	12:amod	SpaceAfter=No
11	/	/	PUNCT	HYPH	_	12	punct	12:punct	SpaceAfter=No
12	visual	visual	ADJ	JJ	Degree=Pos	13	amod	13:amod	_
13	experience	experience	NOUN	NN	Number=Sing	0	root	0:root	SpaceAfter=No
14	.	.	PUNCT	.	_	13	punct	13:punct	_
