AUDIO MERGE / KTBK-1B Passive High Pass Filter

The Audio Merge/KTBK-1B is a dub filter that delivers the same authentic tone as the Altec 9069B, which replicates the passive high-pass filter installed in the MCI console owned by King Tubby, the pioneer of dub music, known as the ""Big Knob.""

The KTBK-1B is a modern revival of the passive high-pass filter found in the MCI console owned by King Tubby, the pioneer of dub music.

The large red knob on his MCI console was known as the ""Big Knob,"" a secret weapon that defined Tubby's sound.

King Tubby's Big Knob (KTBK-1B) is a dub filter that delivers the same authentic tone as the Altec 9069B. It's a 3rd-order variable passive high-pass filter with 10 step-by-step cutoff frequencies, allowing for precise control of the sound's tone. AudioMerge's KTBK-1B is optimized for modern studios and features new controls, a mode selector, and resonance level adjustment.

It utilizes DSP technology and handcrafted custom multi-tap inductor coils to achieve the most accurate frequency response. Initially designed to reduce low frequencies in dialogue and program content, mitigating room resonance, hum, and other low-frequency noise.

An Equalizer with Vintage Flavor for the Modern Studio

For those who demand high-quality music and enjoy the characteristics of a variable passive high-pass filter, King Tubby’s Big Knob (KTBK) delivers the same authentic tone as the Altec 9069B, a vintage equalizer designed in the 1960s, allowing for fine-tuned control over the tone of your sound. The KTBK unit features two additional switches: a mode selector and a resonance level adjuster, allowing you to fine-tune the filter response and adapt it to modern music production workflows. Furthermore, meticulous fine-tuning using DSP technology ensures a high level of reproduction of the Altec sound signature.

KTBK1B Curves

BELL, 600, and NOTCH are different modes that transform the KTBK1B into a unique piece of equipment, increasing its versatility at various stages of music production. The 600 mode replicates the response of the original Altec 9069B. The BELL mode replicates King Tubby's sonic signature, functioning as a peak-resonant high-pass filter (HPF) with no insertion loss, ideal for sweep effects for overdubbing, and featuring a recognizable phaser effect. The NOTCH mode is an Audio Merge exclusive, achieving a response unlike anything seen in other equipment. In fact, it behaves like a VARI-NOTCH, varying the attenuation level and Q factor depending on the cutoff and BELL level.

A Vintage Equalizer

Passive filters are extremely sensitive to impedance matching. Originally, the Altec 9069B was designed to operate with a 600Ω impedance input/output (IO). However, the AudioMerge KTBK-1B features a mode control switch to replicate the original HPF response while accommodating a wide range of equipment.

Sweep the Sound Like a Dub Master

Sweep and layer your sound with the KTBK filter to achieve an unparalleled sonic signature. It's the perfect gear for creating dynamic mixes with lo-fi tones! Digitalization has transformed the way we record, produce, and process music. Now is the time to fuse the best of the analog and digital realms and explore new possibilities.

Handbuilt with Love and Customized Features

Each unit is hand-assembled and subsequently validated at AudioMege's factory in Barcelona. The multi-tap inductors are custom-designed to achieve the most accurate cutoff frequency based on frequency response and phase distortion analysis using various cores and coil winding techniques. The customized stepped rotary switch provides extremely smooth rotational resistance, ensuring creative freedom during performance.

MAIN

Number of channels: 1

Frequency response: +/-0.5dB 10Hz-70kHz @ OFF

Input impedance: 600Ω

Output impedance: 600Ω

Insertion loss

BELL & NOTCH: 0dB

600: 6dB

Max input level: +38dBu

THD: < 0.01% @ 1kHz +17dBu

Power Consumption: 0W - completely passive

True Bypass: yes

CUTOFFS & MODES

Number of cutoffs per filter: 10

Cutoffs: 70C, 100C, 150C, 250C, 500C, 1KC, 2KC, 3KC, 5KC, 7.5KC

Modes: 600, BELL and NOTCH

Damping levels (BELL & NOTCH): 6

IO & DIMENSIONS

Input & Output: 1/4""

Height: 52.3mm (box) + 4.7mm (supports) ~ 2.06"" + 0.19""

Width: 125.1mm ~ 4.93""

Depth: 164mm ~ 6.46""

Weight: 1.2kg

About AudioMerge

AudioMerge is an audio equipment brand based in Barcelona, ??Spain.

Founded in 2021 by two Spanish sound engineers, this brand
develops and manufactures high-end analog filters for dub music and dance music artists of various genres.