Quartz Crystal Singing Bowls come in a variety of sizes. The frosted or classic frosted bowls range in size from 7” to 28” though bowls under 8” can be notoriously hard to sing. Within this size range you will find bowls ranging from the low 3rd octave in the larger bowls to the high 5th octave in the smallest of frosted bowls.
Crystal bowls aren’t manufactured with the note in mind. The bowls are created and then tested to see what note has resulted. This explains why some notes don’t appear in some sizes, for instance in the 3rd octave the larger bowls tend to range toward the C, and D notes from the 28” end of the spectrum. As you move toward the 20” bowls the instance of notes like E and F start occurring more. As you move further down in size the bowls in the 18” and 16” sizes can feature the G and A note. The 14” and 13” size of the bowls show the transition point into the 4th octave, some bowls however still be in the 3rd. Along with the octave change we see a broad range of notes covered including the A and B notes. The 12” bowls will show a strong instance of C note bowls and the 11” will feature a higher instance of the F note. The 10” size is firmly rooted in the 4th octave and centers on the D note while the 9” and 8” bowls move higher in the scale topping out at a rare 5th octave C note in the 8” size.
The thickness of the singing bowl definitely has an effect on what note the bowl sings at. As arule the thicker the bowl the higher the note.
The difference in tone between the frosted style bowl is noticeable by ear. The different techniques of manufacture are the cause of this and the effect is predictable. The clear Quartz bowls are available in sizes from 6” up to 12”. As a general rule the clear bowls will be an octave lower than the frosted bowls of the same size.
The Empyrean and HQ bowls tend to follow the rules of the frosted bowls closely, as they are a refined version of these bowls so the general size and octave measurements will be the same. The difference is in the playability of these bowls.