In experimenting with different exotic woods as alternate shell making materials, DW's Custom Shell Shop discovered that in addition to the different tonal qualities inherent in every unique type of wood, slight alterations in the shell's construction can also greatly influence sound. Some of the woods sampled possessed a vertical grain pattern that when tested, dramatically lowered the pitch of the shell. Thus, HVLT (Vertical Low Timbre) was born. For those players who prefer a lower overall tone while still maintaining maximum resonance and attack, VLT can be ordered as an option on all Collector's Series Maple Drums.