[noun (sound/voice)] + が + 聞こえる [place/source] + から + [noun] + が + 聞こえる
[noun (sound/voice)] + が + [na-adj] + に + 聞こえる [noun (sound/voice)] + が + [i-adj 〜い → 〜く] + 聞こえる [sentence (plain)] + ように + 聞こえる
[person] + に + (は) + 聞こえる (receiver marked with に)
きこえる聞こえる (きこえる) is an intransitive verb meaning "to be audible", "to be heard", or "to sound (a certain way)". It describes sounds that naturally reach the listener's ears, without any deliberate effort to listen.
While きく聞く means "to listen" or "to hear" (an active, intentional action), 聞こえる describes sounds that are naturally perceptible – they come to you whether you intend to hear them or not.
The sound source is marked with が, not を, because 聞こえる is intransitive – the sound is the subject, not the object.
This is the most common usage. It expresses that a sound reaches the listener.
When asking whether someone can hear something:
聞こえる can also mean "to sound (like)" when combined with an adjective or a noun + に.
Adj-く + 聞こえる: Describes how something sounds.
Noun + に聞こえる: Expresses that something sounds like a particular thing.
聞こえる can also refer to one's ability to hear in general.
聞こえる is a る-verb (ichidan verb) and conjugates normally: