Bhashya
यस्मादेवं साम, तस्मादस्य नैरन्तर्येणोद्धारः स्पष्टीक्रियते ।तत्र मूलमन्त्रप्रथमपादाक्षरेष्वष्टसु मुखहस्ताभ्यां हस्ताङ्गुष्ठोत्तमपर्वोच्छ्रयेण आद्यमक्षरद्वयं मुखेन प्रागाय तृतीयमक्षरं कनिष्ठिकामूलपर्वस्पर्शेन तथैव मुखेन प्रागाय चतुर्थं पञ्चमं चैकैकं पृथक्पृथगङ्गुष्ठोत्तमपर्वतर्जनीस्पर्शतसंनिहिताङ्गुल्युपकनिष्ठिकाकनिष्ठिकामध्यमध्यपर्वस्पर्शेन तथैव मुखेन प्रागायेत् ।षष्ठमङ्गुष्ठोत्तमपर्वोच्छ्रयेण तथैव मुखेन प्रागायेत् ।सप्तमाष्टमाक्षरे कनिष्ठिकामूलपर्वस्पर्शेन यथाविहितस्वरैः आद्याक्षरद्वयाद्यतृतीयाक्षरान्त्यचतुर्थपञ्चमाक्षरमध्यषष्ठाक्षराद्यसप्तमाष्टमाक्षरान्त्यैः अप्रमत्तः तथैव मुखेन गायेत् ।तथैव तृतीयषष्ठयोरङ्गुलीभ्यां दीर्घं गृह्णीयात् ।एवं द्वितीयतृतीयचतुर्थपादाक्षरेष्वष्टसु साम गेयम् ।द्वितीयपादे षष्ठं दीर्घं तृतीये , चतुर्थमक्षरं दीर्घं चतुर्थे षष्ठं दीर्घमिति शुद्धं साम; साङ्गं चेत् प्रथमपादान्ते प्रणवं निक्षिप्य द्वितीयपादान्ते सावित्रीं तृतीयपादान्ते यजुर्लक्ष्मीं चतुर्थपादान्ते नृसिंहगायत्रीं गायेत् ।स्त्री चेत् शूद्रश्चेत् एतत्रितयं विहाय शुद्धं साम गायेत् ।एष नैरन्तर्येण सामोद्धारः; उच्चारणस्यातिदुर्लभत्वादतिरहस्यत्वाच्च लिखितोऽपि न लिखित्वा प्रदर्श्यते, वाचैव स्पष्टीक्रियते इति ।य एवम् उक्तप्रकारेण वेद उपास्ते ।इति-
In plain words
Because the chant is built this way, its unbroken thread can now be shown clearly. Take the eight syllables of the first quarter of the root mantra, and use mouth and hand together. Raise the tip of the thumb and sing the first two syllables aloud. Touch the base joint of the little finger, and sing the third the same way. For the fourth and fifth, touch each one separately -- the thumb at the index finger, then the middle joints of the ring finger and the little finger beside it -- singing each aloud in turn. Raise the thumb-tip again for the sixth. For the seventh and eighth, touch the base of the little finger, and let the pitch fall where it belongs: high at the start of the first pair, low at the close of the third, level through the middle of the fourth and fifth, high again at the sixth, low at the close of the seventh and eighth. Sing with full attention. Hold the long note on the third and the sixth with the fingers. The same pattern carries the second, third, and fourth quarters: the sixth syllable held long in the second, the fourth held long in the third, the sixth held long in the fourth. That is the plain form of the Sāma. Sung with its ancillary parts, the Praṇava closes the first quarter, the Sāvitrī the second, the Yajur-Lakṣmī the third, and the Nṛsiṃha-Gāyatrī the fourth. A woman or a śūdra sets these three aside and sings the plain Sāma alone. This is how the Sāma is drawn out without a break. Because its sound is so rare to come by and so closely guarded, it is never shown in writing, even where it has been written down -- only the living voice makes it plain. Whoever knows it in just this way, and lives with it in meditation --
Close to the Sanskrit
Since the Sāma is thus [structured], therefore its unbroken extraction is made clear. There, among the eight syllables of the first quarter of the root mantra, by mouth and by the two hands: by raising the tip joint of the thumb, one should sing forth by mouth the first two syllables; the third syllable, by touching the base joint of the little finger, likewise by mouth; the fourth and the fifth, each one separately, by touching -- with the thumb's tip joint touching the index finger -- the middle joints of the adjoining ring finger and little finger, likewise by mouth, one should sing forth. The sixth, by raising the tip joint of the thumb, likewise by mouth one should sing forth. For the seventh and eighth syllables, by touching the base joint of the little finger, with the tones as prescribed -- the accent at the beginning for the first pair of syllables, at the end for the third syllable, in the middle for the fourth and fifth, at the beginning for the sixth, at the end for the seventh and eighth -- attentively, likewise by mouth, one should sing. Likewise, for the third and sixth, one should hold the long note with the fingers. Thus, among the eight syllables of the second, third, and fourth quarters, the Sāma is to be sung. In the second quarter the sixth is long, in the third; the fourth syllable is long, in the fourth the sixth is long -- thus is the plain Sāma. If with the ancillary parts: having inserted the Praṇava at the end of the first quarter, one should sing the Sāvitrī at the end of the second quarter, the Yajur-Lakṣmī at the end of the third quarter, the Nṛsiṃha-Gāyatrī at the end of the fourth quarter. If a woman, or if a śūdra, having set aside this triad, one should sing the plain Sāma. This is the unbroken extraction of the Sāma; because the pronunciation is extremely rare to obtain and extremely secret, even when written it is not shown by writing -- it is made clear only by voice. Whoever thus knows and meditates upon it in the manner stated --