Dizengoff Audio is a Chicago based manufacturer of high-end hardware preamplifiers and signal processors. The concept is simple but powerful: Use modern production techniques and planning to create affordable but expensive-sounding boutique-style analog gear. Meticulous analysis of the specifics of what has made certain vintage units so sought after has resulted in a range of products that you simply have to listen to for yourself to believe, especially given the price tag. Dizengoff sources as many parts as they can locally and all assembly and testing is done inhouse. These products can proudly proclaim to be Made In America.
The Dizengoff Audio DA2 is a tribute to the venerable RCA BA2C tube preamp. RCA’s BA2C found wide use in film, broadcast, and recording during the 1950’s. We like to think of it as the “little brother” to the RCA OP6 because they use the same tube. The DA2 has wonderful headroom, and it packs a nice low-mid wallop. The tone is smooth, warm, and sort of heavy–just what you’d expect from an American tube design of this era.
Signal transformers are wound in the work shop in Chicago. The DA2 uses a hi-nickel input (80% nickel) and lo-nickel (45% nickel) for excellent fidelity. The transformers are based on early Peerless designs, and their frequency response is flat from 10Hz to 50kHz. The power supply is internal. Like the D4 and D864, it’s built around a Japanese Nippo Steel R-core power transformer. It has extremely high efficiency and low noise compared with traditional E-I core transformers and plays a significant part in achieving the DA2’s low noise performance.
The Dizengoff D4 is a tribute to a rare and much loved British tube console from the 1960’s. The original circuit was designed by the Recording Engineering Development Department as a replacement for the Siemens V72S amp cards used in an earlier British console. It featured three gain settings (+36, +40, and +46), and a ‘fine trim’ knob that allowed the user to trim gain by a few dB. The D4 has expanded that range from +20 up to +60 using a 12 step rotary attenuator. Like the original design, the D4 ‘trim’ control allows the user to fine tune the gain by 2-4dB depending upon the gain switch setting.
The sound is huge and open–heard on albums recorded by The Beatles, Pink Floyd, and The Zombies between 1964 and 1968. It has incredible detail, and the kind of wonderful coloration that only an EF86 pentode can deliver. It’s often considered to be the sound of John Lennon’s “Revolution,” which used two console channels in series to achieve an overdriven sound.
Signal path transformers are custom wound in the work shop in Chicago. They’re based on the transformers used in the original, but they take advantage of modern materials. The input transformer is a hi-nickel (80% nickel content) and the output transformer is a lo-nickel (50% nickel) for excellent fidelity. The power supply is internal. It’s built around a Japanese Nippo Steel R-core power transformer, which has extremely high efficiency and low noise compared with traditional E-I core transformers and plays a significant part in achieving the D4’s low noise performance.