The Mercury EQ-P2 is two independent (dual mono) channels of our popular Mercury EQ-P1 (mono) Studio Program Equalizer in a 3U package. The Mercury EQ-P2 is based on the vintage Pultec EQ-P1a circuit. The Mercury EQ-P2 has a passive EQ circuit with a fully balanced (push-pull) gain make up amplifier. This new Mercury production utilizes only the highest quality passive components, while remaining true to the original and like all Mercury products has transformer balanced input and outputs. Besides a much more powerful and stable power supply and running DC on the heaters, rather than AC, the only other modernization is one of Mercury EQ-P2's most popular features, the Mercury IST Switch.

The Mercury I.S.T. Switch offers the choice to switch the Interstage Transformer in or out of the circuit. Giving engineers a choice with a flick of a switch between the standard Mercury warm, musical, "vintage" tone with the I.S.T. Switch not engaged (out) or a much more open and airy version of the same full, warm tone with the switch engaged (in). In the original Pultec EQP the Interstage transformer was always in the signal path. With the I.S.T. Switch engaged and the interstage transformer not in the circuit, there is slight widening of the sound and slightly more open top end. Many of today's engineers value this feature on the Mercury EQ-P1 and now the Mercury EQ-P2 Studio Program Equalizers to have choice between two great, but different sounds without changing their frequencies or setting and hearing the change instantly. Note: With the I.S.T. Switch engaged or not, the input and output transformers are always in the circuit.

The EQ-P2 amplifier uses one 12AX7 tube and one 12AU7 tube per channel.

Frequencies
Low Frequency Select (CPS; Cycles per second): 20, 30, 60, 100, 200 Hz
Low Frequency Boost Control: Shelf Boost, 0dB to +13dB
Low Frequency Attenuate Control: Shelf Atten. 0dB to -17dB
High Frequency Select (KCS; kilocycles per second ): 3, 4, 5, 8, 10, 12, 16 kHz
High Frequency Boost Control: Shelf Boost, 0dB to +16dB
High Frequency Attenuate Control: 10k Shelf Attenuate, 0dB to -16dB