Manley Laboratories Stereo Pultec-Style EQ

Manley's Stereo Pultec EQP-1A, passive tube EQ on "stereoids"

The Manley Stereo Pultec EQP-1A delivers dual-channel passive equalization based on the acclaimed Pultec topology, engineered specifically for stereo mixing and mastering applications. It does work equally well on 2 individual mono sources, like bass drum and vocals! Hand-built in California, this EQ combines passive inductor-based EQ networks with all-tube makeup gain amplification. That's how it provides the phase-coherent frequency shaping and harmonic character that define the Pultec sound.

The Manley Stereo Pultec is essentially two matched Enhanced Pultec EQP-1A channels housed in a single 2U chassis. This dual-channel design is optimized for processing stereo program material, such as a mix bus or stereo sub-groups. While the sonic characteristics and controls of each channel are identical to the mono version, the stereo unit offers the convenience of simultaneous control and a unified power supply, making it an ideal choice for maintaining phase and sonic consistency across the left and right channels of a mix.

The simultaneous Boost and Cut feature is central to the "Pultec magic." When applied to a stereo mix, boosting a low frequency and cutting that same frequency (or an adjacent one) creates a signature resonant shelf. This preserves the low-frequency weight while tightening the mid-bass, adding a powerful, cohesive "punch" to the entire stereo image without muddying the mix. When applied to the high frequencies, it adds "air" and sparkle while controlling harshness. Since the controls are ganged for both channels, the effect is perfectly mirrored across the stereo field.

The passive EQ circuit of the Pultec naturally attenuates the signal, requiring a dedicated amplifier to restore the gain. Manley's all-tube make-up gain amplifier, built around a 12AX7 and a 6414/5965, provides the immense headroom and rich harmonic content that defines the Manley sound. This single-ended, Class-A tube amplifier restores the signal cleanly and musically, imparting a subtle, highly desirable warmth and liquidity that is crucial for the "extra-beefy sound" of the Manley Pultec.

The Stereo Pultec offers two flexible output options per channel for easy interface and sonic variety. It includes a Balanced, Transformer-Coupled XLR Output via the custom MANLEY 9611 transformer, which provides a robust signal with a touch of "big iron" character. It also offers a Direct Capacitor-Coupled Unbalanced Output via a 1/4" jack, which provides a cleaner, more transparent signal path. This versatility allows the engineer to choose the best sonic flavor and interface for the subsequent gear in their chain.

Manley's "Enhanced" Pultec design includes extra selectable frequencies that were not present in the original antique Pultec units. These additional bands expand the unit's versatility for modern production. While the precise additional frequencies are part of the overall updated design, they ensure that the EQ covers crucial low-end resonance points and ultra-high frequency "air" that are often missed by the vintage units.

Phase-coherent stereo equalization with passive topology

The passive architecture of this EQ maintains phase relationships critical for stereo imaging while delivering musical frequency contouring across both channels. The passive EQ network ensures minimal phase shift, allowing broad tonal adjustments to the complete stereo field without compromising spatial information. From low-frequency reinforcement to high-frequency extension, the Stereo Pultec adds dimension, weight and clarity to mixes!

Enhanced frequency selection with all-tube amplification

Manley's implementation expands upon the original design with additional frequency selections, extending tonal control beyond the classic Pultec architecture. All-tube makeup gain stages restore signal level with harmonic enhancement while the robust power supply ensures extended headroom and low noise performance. Conductive plastic potentiometers provide continuously variable control, with silent operation and long-term reliability throughout the signal path.

California craftsmanship since 1990

Manley has manufactured and refined Pultec-style EQs since 1990, maintaining the legacy of this foundational EQ design. Each unit is hand-assembled in California with premium components including custom Manley 9611 output transformers for balanced, transformer-coupled outputs. These EQs embody more than 3 decades of Manley engineering expertise. A trusted workhorse and favorite in many professional recording, mixing and mastering studios around the world.