Jaiminīya (Talavakāra) Brāhmaṇa 31.185

Now, the Gauṅgava: the sāman praises the deity.
This sāman praises the deity; thereby the sacrificers come to have their wishes realized.
The gods and the Asuras vied for cattle.
The Asuras went down to the ocean together with the cattle.
The gods desired: "May we wrest away the cattle of the Asuras!"
They saw this sāman.
With it they praised.
With it they wrested away the cattle of the Asuras.
They said: "We have wrested away cow after cow (gāṃ gām) of the Asuras!"
That is the Gauṅgava-ness of the Gauṅgava.
This is a sāman conferring cattle.
He wrests away cow after cow of his hateful rival, secures cattle, and becomes rich in cattle, who knows thus.
Having slain the Asuras with the Gauṅgava, the gods made a clamor (ghoṣa), 'gaṃ-gaṇam'.
That, too, is the Gauṅgava-ness of the Gauṅgava.
And it is a slayer of rivals.
He slays his hateful rival, who knows thus.
It is sung as if upward and as if crosswise.
That which is sung as if upward is the form of the Bṛhat; that which is as if crosswise is that of the Rathantara.
This indeed is the fullness of the Chandomas: that it has both forms.

Now, the Samanta.

Indra and Agni desired: "May we be contiguous (samanta); may we attain equal prosperity!"

They saw this sāman.

One saw one half, the other the other half.

Bringing its two ends together, they joined them (samadhattām).

Because they joined them, that is the Samanta-ness of the Samanta.

With it they praised.

Then indeed they both became contiguous; they attained equal prosperity.

That brahman is Agni; nobility is Indra.