User Manual
30
V 1.1
2022-09-12
User manual for MERUS™ audio amplifier configurato
r
MA2304DNS/MA2304PNS
DSP audio blocks
This can be useful when designing second-order crossover filters, where there is a 180-degree phase shift
between the low-pass and high-pass filter outputs.
Bypass
When configured as bypass, the input signal flows to the output unaffected.
Low-pass and high-pass filters
The low-pass and high-pass filters have two controls: a filter subtype dropdown menu and a cut-off frequency
control:
The image below shows the options that are available in the filter subtype dropdown menu:
Each filter subtype represents one of many analog prototype filters. The single-pole filter option has a
20 dB/decade roll-off while the second-order filter options have a 40 dB/decade roll-off, and so on.
Using a single-pole high-pass filter (e.g., less than 50 Hz) is recommended to avoid any offset artifacts.
A fourth-order filter requires the user to configure two consecutive biquad blocks. For example, if a fourth-
order Linkwitz-
Riley filter is desired, the first biquad should be configured as “4th order Linkwitz
-Riley (1st
biquad)” and the second biquad should be configured as “4th order Linkwitz
-
Riley (2nd biquad)”.
The second-order custom filter provides the option to manually enter the filter Q-value. For example, a Q = 0.5
results in a critically damped filter while a Q = 0.707 (e.g., Butterworth) results in a maximally flat (monotonic)
filter.
