Most audio stages operate with ☒0V supply rails, but the make‑up gain stage operates on ☒8V to provide additional headroom. Even the centrally mounted stereo link switch is screened from the mains section by a steel box section! Each audio channel's main PCB carries its own rectifiers, generously specified reservoir and smoothing capacitors, and five separate voltage-stabilising circuits for the different amplifier stages, with the regulating power-transistors mounted on a shared heat-sink fin running across the centre of each board. Separate secondary windings are provided for each of the two channels, the connections for which pass through rubber‑grommetted holes in the steel partition panels. The partitioned central section contains all the mains wiring between the IEC inlet, an EMI filter block, the on‑off switch and the custom torroidal transformer. Internally, this device is constructed to a very impressively high standard. Pin 1 of each XLR is bonded directly to the chassis in the recommended way and, not surprisingly, the Preceptor passed the 'Wendt Hummer' test with flying colours: there's no risk of ground‑loop hums here! To the left and right are pairs of XLRs for the balanced line inputs and outputs, along with quarter‑inch TRS sockets to accept balanced side‑chain input signals. On the rear panel, an IEC mains inlet socket (with integral fuse holder) occupies the centre, with a voltage selector switch (230/115V AC) immediately above. A useful benefit of this construction is that there's plenty of front‑panel real-estate available, allowing nicely spaced and generously proportioned controls and metering. Part of the reason for the 3U height is to accommodate the chunky custom 70VA torroidal mains transformer (with both electrostatic and electromagnetic shielding), which is mounted edge‑on in a central, steel‑partitioned section of the case. The black-painted steel case, which has a glossy front panel, stretches 245mm behind the rack ears and weighs a fairly substantial 6.4kg. The Preceptor Model A is an unusually large (3U rack‑mounting) two‑channel dynamics processor that uses mostly discrete, class‑A, solid‑state circuitry.
![shadow hills mastering compressor rack mounted shadow hills mastering compressor rack mounted](https://thumbs.dreamstime.com/b/compressor-rack-mounted-audio-limiter-74828277.jpg)
The current range includes the Preceptor Models A and T (see the box elsewhere in this article), and the Compactor - and all are compressor‑limiters with interesting design features and superb build quality.
SHADOW HILLS MASTERING COMPRESSOR RACK MOUNTED PROFESSIONAL
Generic Audio are relatively new Polish manufacturers who have launched a small range of high-quality hardware, all designed with a passion for professional audio, and with fanatical attention to detail.
![shadow hills mastering compressor rack mounted shadow hills mastering compressor rack mounted](https://i.pinimg.com/736x/d6/da/ca/d6daca0df548e020600ad63a023c88ea--studio-gear-music-production.jpg)
From a new and little-known Polish company come two compressors made with a "fanatical attention to detail”.