The Psalms certainly are not Law (Torah).
The Psalms are collections of songs, hymns, and writings that express worship to God.
The Hebrew title of Psalms is
Tehillim means “praises”.
The idea that
corporate singing is done aloud is a redundancy.
To sing, one
audibly vocalizes (makes a musical noise).
To sing corporately,
one joins with others who are singing.
The word "aloud" does not necessarily mean LOUD.
Whether one sings LOUD or softly, doesn't really matter.
It means
audibly,
not silently,
using one's voice,
but to do it with joy, exultantly, fully expressing enthusiasm.
So when a stage performer '
whispers a song' with amplification is it really a whisper?
...or is it merely a vocal technique to express intimacy or heartfelt devotion?
Sing for joy to God our strength;
Shout joyfully to the God of Jacob.
Ps 81:1 NASB
Sing aloud unto God our strength:
Make a joyful noise unto the God of Jacob.
Ps 81:1 AV1873
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Come, let’s sing for joy to the Lord,
Let’s shout joyfully to the rock of our salvation.
Ps 95:1 NASB
O come, let us sing unto the Lord:
Let us make a joyful noise to the rock of our salvation.
Ps 95:1 AV 1873
Our song leader often gets so enthusiastically loud when he sings that it hurts my ears (I tell my wife that he yodels)
That, combined with the amplification techniques make it so loud that I often can't hear my own voice.
(Somehow I can still hear the woman far across the room that sings like an alleycat in heat.)
So I sing with emotion but quietly so as not to cause a disturbance.
Rob