Solid State Logic 611EQ 500 Series Parametric Equalizer

The Solid State Logic 611EQ parametric equalizer brings the classic 4-band EQ design from SSL’s legendary E Series consoles into a single mono 500 Series module. With a dual-mode design, the 611EQ lets engineers switch the midrange bands between the celebrated “Brown Knob” and “Black Knob” EQ circuits, giving access to two distinct eras of SSL tone in one unit. As a result, studios can dial in the warmer, more musical character of the early ’80s Brown Knob EQ or the wider-range, more surgical Black Knob circuit, depending on the source and the sound they’re after. In addition, both the high and low frequency bands can be toggled between shelf and bell curves, giving engineers the flexibility to make broad tonal adjustments or zero in on problem frequencies with precision. Marshall Music South Africa stocks the Solid State Logic 611EQ parametric equalizer for studios across South Africa wanting classic SSL E Series EQ tone in their 500 Series racks.

Why the Solid State Logic 611EQ Parametric Equalizer Covers Every Frequency Range

The 611EQ’s frequency coverage is extensive: the low-frequency band sweeps from 30Hz to 450Hz, the low-mid band covers 200Hz to 2.5kHz, the high-mid band ranges from 600Hz to 7kHz, and the high-frequency band offers selectable frequencies from 1.5kHz to 15kHz. However, the real character comes from the dual-mode midrange bands — in Brown Knob mode, engineers get up to 15dB of cut or boost with SSL’s signature musical curve, while Black Knob mode extends the range to 18dB of cut or boost for more aggressive tonal shaping. Both midrange bands are fully parametric, with independent controls for gain, frequency, and Q, giving engineers complete control over the shape of each adjustment. Whether you’re warming up a vocal with Brown Knob curves, carving out space for a guitar with Black Knob precision, or shaping the top and bottom end with switchable shelf/bell filters, the Solid State Logic 611EQ parametric equalizer delivers two generations of SSL EQ in a single 500 Series slot. Marshall Music South Africa can help South African studios add this versatile EQ module to their racks.

Tech Specs

• Format: 500 Series mono 4-band parametric equalizer module
• EQ Modes: Switchable “Brown Knob” (15dB cut/boost) and “Black Knob” (18dB cut/boost) midrange circuits
• Low-Frequency Band: 30Hz-450Hz, switchable shelf/bell
• Low-Mid Band: 200Hz-2.5kHz, fully parametric (gain, frequency, Q)
• High-Mid Band: 600Hz-7kHz, fully parametric (gain, frequency, Q)
• High-Frequency Band: Selectable 1.5kHz-15kHz, switchable shelf/bell
• Design Heritage: Based on SSL E Series console EQ circuits

Solid State Logic

Founded in 1969 by Colin Sanders, Solid State Logic began life building switching systems for pipe organs before evolving into the world’s leading manufacturer of analog and digital audio consoles. SSL pioneered industry-defining technologies — including motorized fader automation and total recall of mixer settings — and its large-format consoles became the backbone of major recording, broadcast, film, and live sound facilities worldwide, shaping the sound of countless hit records.

In recent years SSL has brought that console DNA into the personal and project studio space, with a range of award-winning audio interfaces (SSL 2, SSL 2+, SSL 12, SSL 1), compact mixers, control surfaces, channel strips, and processing plug-ins. Renowned for high-bandwidth, low-distortion signal paths and the iconic “SSL sound,” the brand remains a benchmark name across professional and home studios alike.

Learn more about Solid State Logic

View more Solid State Logic at Marshall Music

Why Buy From Marshall Music

At Marshall Music, we’re all passionate and highly experienced musicians that love what we do. Family run and family owned for over 35 years, we stock a huge variety of the very best brands in the world of musical instruments, music technology, professional audio and accessories. At Marshall Music, you’ll get the right advice – exactly what you need to make the best possible purchasing decision. We’ll do all we can to make sure you get the right thing at the right p      rice as efficiently as possible – leaving you with a smile on your face!