UREI Model 546 (1980)
Eight bands of parametric EQ in one rack unit - the flexible, surgical counterpart to UREI's graphic equalizers.
Overview
UREI's Model 546 is the dual-channel member of the company's parametric equalizer line. It was announced in 1980 and sits alongside the single-channel Model 545. The 545 gave an engineer four bands. The 546 doubles that: two independent channels, each with four sections of parametric equalization, all continuously variable in bandwidth, frequency, and boost or cut. That's eight parametric filters in one package. Per UREI's own product literature, a special Expanded Single Channel mode cascades all eight sections for mono work, which makes the 546 a serious surgical tool for a single source.
The design is built around flexibility rather than fixed-frequency compromise. Each filter section has its own bypass switch, and so does each channel. You can compare a curve against the dry signal, or pull the processor out of the chain entirely, without repatching. Tunable end-cut filters at the band ends let the operator restrict bandwidth by rolling off the extremes before the parametric stages do their work. Gain is variable over a 30 dB range. Inputs are balanced or unbalanced bridging. Outputs are transformer-isolated, a detail engineers in broadcast and studio plants tend to care about more than the spec sheet suggests.
UREI ran a steady advertising campaign for the equalizer line through the early 1980s, and the 546 appears in those pages as the parametric flagship of the family. The pitch was blunt about who the product was for. In the studio, in sound reinforcement, in radio and television production, the copy read, a good engineer relies on talent and expertise, and on UREI's reputation for professional performance. db (October 1980, p.55) carried the same campaign, which framed the equalizers as instruments for engineers who "correct or create." The 546, with its continuously variable bandwidth and frequency, is the one built for the "create" side.
The parametric approach sets it apart from the graphic models in the same catalog. UREI's Model 535 dual graphic offers ten fixed ISO-octave bands per channel with ±12 dB of boost or cut, and the Model 537 third-octave graphic delivers 27 fixed bands. Those are fast, familiar tools. The 546 asks the operator to choose the frequency, the width, and the amount of the correction. That's more decisions per band, but far more control when a problem sits between the fixed centers of a graphic. UREI also offered the Model 539 room equalization filter set, a 27-band ISO third-octave design with calibrated attenuation from 0 to -15 dB, for room tuning rather than creative shaping.
The control surface is deliberately large and easy to adjust, and the unit carries multi-point overload detection circuitry — a sensible inclusion for a processor likely to live in a patch bay and see hot console levels. The 546 was introduced at a moment when UREI was expanding its signal-processing range; the same 1980 announcement that introduced the dual parametric also brought the Model 1178 dual peak limiter, a two-channel version of the 1176LN, and the Model 562 feedback suppressor with five active notch filters. Recording Engineer (October 1980, p.41) covered the launch as part of UREI's new-product push that year.
For collectors, the 546 is not the 1176 or the LA-2A, the compressors that command the serious money and the endless clone market. It is a genuine UREI professional equalizer from the company's active years, with transformer-isolated outputs and the build quality the brand was known for. The parametric format also means it has aged better than some fixed-band designs, since an engineer today can dial in exactly the curve they want rather than working around preset centers. Values and current market pricing are not documented here. The usual advice for vintage UREI applies: check the switches and pots for noise, confirm the transformer-isolated outputs are intact, and verify the bypass switching works on every section.
Mix (September 1980, p.16) ran the same UREI equalizer campaign, and the message across all of these placements was consistent: the 546 was sold as a professional's instrument, not a consumer tone control. That framing is fair. It is a tool that rewards an operator who knows what frequency they want to move and how wide they want the move to be — and it punishes nobody who leaves it bypassed.
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