Zoom H4essential Operation Manual page 7

Dual A/D converter circuit overview
For each input circuit, the H4essential has two A/D converters with different input gains. This design
enables high-quality audio recording without the need to adjust gain settings, a step that is normally
indispensable.
NOTE
On the H4essential, only the INPUT 1 and INPUT 2 jacks have dual A/D converter circuits.
Providing amazing dynamic range
By combining two A/D converters, a wide dynamic range not possible with a single A/D converter has been
realized.
・Airplane
・Nearby thunder
・Train passing on tracks overhead
・Inside train
・Shouting
・Grand piano
・Noisy street
・Chimes
・Ordinary conversation
・Whispering
・Quiet library
・Late night in suburb
Conventional equipment
Input gain adjusted to
desired recording volume
7
Dual AD converters
Low-gain
AD converter
AD converter
switches in
response to
input level
High-gain
AD converter
Wide dynamic range covered
by two AD converters