Pultec EQP-1A is a passive equalizer with an operational amplifier, featuring a versatile range of equalization curves. It offers precise control over the frequency response of audio signals, allowing users to boost or attenuate specific frequency ranges. With its continuously variable controls, the EQP-1A enables smooth and gradual adjustments, avoiding abrupt changes in level or noise. The device's no-loss, no-gain design ensures that the overall signal level remains consistent.