वैदिकतन्त्रे शाखाविशेषाः

कस्तूरिलेखः

The most recent common ancestor most likely was formalized by prājāpatyas, though the ritual is of Indo-European provenance. Still, different vedic shākhās add their specialty into the basic format. ..

One outlier is Atharvanic kauśika sūtra- the single fire pākatantra procedure he outlines is as complicated as an işți. Anyways we use a simplified version which according to tradition is from atharvavedic nakshatra kalpa. The atharvanic speciality is the preparation of shāntyudaka or pacificatory water.

Adding jayādi oblations appear to be yajurvedic specialty.

Coming to sāmavedins, … One speciality of theirs is something called prapada japa - done just after appointment of brahmā priest and offering of an idhma in the fire. The prapada is a long yajush that starts with “oM tapashcha tejashcha…”. Something that sūtras won’t explicitly tell you and which you learn only from tradition is this- there’s an internal omkāra in the prapada mantra. You have to do a dhyāna visualizing the yajñaphala. During the internal oMkāra. For e.g., if you are doing a sāmavedic homa for wealth acquisition, you’re supposed to visualize the acquisition of cattle and wealth during oMkāra.

Another salient point is that they employ oblations with actual sāmans. Using the same example above, the sāman tune on “bhadro no agnerāhuto” ŕk is sung, followed by “agnaye svāhā, agnaya idam na mama”. 1000 such ghee oblations. This is the main homa. Vāmadevya sāman is sung after uparişțāttantram.

So, the prapada, deployment of sāmans in pradhānahoma and vāmadevya in the end are specialities of sāmavedins.