A simple voltage divider will work but will broaden the band pass.
simulate this circuit – Schematic created using CircuitLab
As per GodJihyo's comment \$R_2\$ should be \$400\Omega\$ for 20% below.
A simple voltage divider will work but will broaden the band pass.
simulate this circuit – Schematic created using CircuitLab
A simple voltage divider will work but will broaden the band pass.
simulate this circuit – Schematic created using CircuitLab
As per GodJihyo's comment \$R_2\$ should be \$400\Omega\$ for 20% below.
A simple voltage divider will work but will broaden the band pass.
simulate this circuit – Schematic created using CircuitLab