True Thomas laid his harp away,
And louted low at the saddle-side;
He has taken stirrup and hauden rein,
And set the King on his horse o' pride.
"Sleep ye or wake," True Thomas said,
"That sit so still, that muse so long;
Sleep ye or wake? -- till the latter sleep
I trow ye'll not forget my song.
"I ha' harpit a shadow out o' the sun
To stand before your face and cry;
I ha' armed the earth beneath your heel,
And over your head I ha' dusked the sky.
"I ha' harpit ye up to the throne o' God,
I ha' harpit your midmost soul in three;
I ha' harpit ye down to the Hinges o' Hell,
And -- ye -- would -- make -- a Knight o' me!"
(Rudyard Kipling, from the Last Rhyme of True Thomas)
There's nothing more silly about the Bard throwing songs at the enemy than about the Wizard shouting silly chants and waving her arms about. Music is magic.
And he was doing all that while dodging dragon fire? Impressive!

But seriously... Yes, singing or playing a musical instrument to make magic is really no different than chanting words and making gestures. Actually it is almost exactly the same when you think about it. Which is why I think the current 5e Bard makes sense as a full, 9 spell level, casting class.