Pultec EQP-1A Program Equalizer

The Legacy Of The Pultec Equalizer

Designed by Pulse Techniques’ Eugene Shenk and Ollie Summerland, each EQP-1A equalizer was often built to order, inevitably making the boutique company’s products a rare commodity in the secondhand gear market. While many have tried to imitate Pultec’s EQP-1A since, few have been able to come close to truly emulating the EQ’s classic sound.

Recreating a Classic Equalizer

In order to properly recreate the EQP-1A, PhD., Electrical Engineer and Materials Scientist Dr. Steven Jackson spent over a decade researching and collaborating, in addition to discussing the project with Eugene Shenk. Working to recreate the exact design of the original equalizer, Jackson studied the specifics of the transformers, circuitry and tubes, in order to accurately build each component to Shenk’s specifications. These aren’t reproductions – These are Pultecs.

The EQ Difference Maker

The EQP-1A is a three-space rack mount unit that features a two-band design that makes it possible to boost extremely low and high frequencies without harming the notes in the middle. With the ability to boost and cut at the same time, the Pultec EQP-1A gives users multiple options of how to treat a shelf frequency, in a way that few other equalizers are capable of achieving.

The Pultec Sound

Several pieces of audio equipment have garnered the praise that they add “something special” to a recording, simply by having signals passed through them. The EQP-1A is one of the few where the difference is definitely noticeable. This Pultec equalizer has a wide-open sound that instantly adds a warm, airy feeling to recordings, reminiscent of the sounds heard on all of your favorite records.

Specifications

• Low shelf boost: +13.5 dB @ 20, 30, 60, 100 Hz
• Low shelf attenuate: -17.5 dB @ 20, 30, 60, 100 Hz
• Mid/high peak boost: +18 dB @ 3, 4, 5, 8, 10, 12, 16 kHz
• Hi shelf attenuate: -16 dB @ 5, 10, 20 kHz
• Input transformer: 600 ohms
• Noise: 92 dB below +10 dBm
• Distortion: ≤ 0.15% at 10 dBm into 600 ohms
• Amplifier: Flat 20 Hz to 20 kHz; +/- 0.5 dB