8. How should compound consonants be chanted? 

When a compound consonant follows a vowel, the first or the next consonant is doubled and chanted as follows:

Note: If the consonant is already doubled, it is not doubled again.

1.  When the first consonant is a plosive:

The first consonant (the plosive) is doubled, and the first of the doubled consonants is held at the articulation point without sound, creating a pause before the following compound consonant. The length of the pause is equivalent to one consonant, which is 0.5 mātrā.

vitryavatu ⇒ vittryavatu (A pause is inserted before "trya")

Note: For gṁ or g + fricative sounds (ś, ṣ, s), the first consonant (g) is not doubled.

Note: When a plosive without aspiration is followed by another plosive or a nasal (ṅ, ñ, ṇ, n, m, ṁ), the second of the doubled consonant may also not produce sound.

2.  When the first consonant is a non-plosive (excluding "r" and "h"):

The first consonant (non-plosive) is doubled and elongated. The length of the elongation is equivalent to two consonants, which is one mātrā. However, if the next consonant is a plosive, the first consonant is not doubled (except when it is a nasal consonant like "ṅ," "ñ," "ṇ," "n," "m," "ṁ"), and the next consonant (the plosive) is doubled instead.

sarasvatī ⇒ sarassvatī (The "s" is fricated and elongated for one mātrā)

upamaśravastamam ⇒ upamaśśravasttamam

3.  When the first consonant is "r" or "h":

The first consonant is not doubled, and the next consonant is doubled instead.

vājebhirvājinīvatī ⇒ vājebhirvvājinīvatī (After pronouncing "r" briefly (0.5 mātrā), the "v" is elongated for one mātrā)

Note: When "r" is followed by a fricative (ś, ṣ, s) + vowel or "h" + vowel, no consonant is doubled. The "r" is pronounced like the vowel ṛ with a one-mātrā length, where the tip of the tongue lightly touches the palate (similar to the Japanese "ru" sound). This is called Svarabhakti.