Gainlab Audio GLA-OC1 Governor

This clever dual‑channel, dual‑slope optical compressor is different from the rest...

Budapest‑based Gainlab Audio are no strangers to the pages of SOS, and the company’s last release, the Bishop channel strip, greatly impressed Matt Houghton in our SOS April 2024 issue. That impressive valve‑based, mono mic/line/instrument preamplifier featured a unique Teletronix LA‑2A‑influenced optical compressor that, interestingly, featured a ‘dual‑slope’, and Matt found it to be both intuitive to operate and capable of delivering a great‑sounding performance. He wasn’t the only user or reviewer to come to that conclusion, so it’s perhaps not surprising that Gainlab decided to created a standalone version of the Bishop’s compressor. The result is the Governor, a dual‑channel optical compressor with valve amplification and an enhanced suite of controls, features and facilities.

Grand Tour

Gainlab’s Governor sits in a 2U, 19‑inch rackmount chassis and is capable of stereo or dual‑mono operation. To make that possible, there are two identical control sets, laid out in horizontal strips that are divided, both visually and functionally, into three sections. The leftmost section of each channel begins with two three‑position metal toggle switches, the first of which selects the compression type (Soft, Medium or Hard) and the second its Tube (valve) Boost frequency profile (Full, Off or Air). As with all the Governor’s toggle switches, yellow LEDs light to indicate the active selection. Sitting next to these is a line of three rotary controls. The first two of these set the thresholds for the dual compression slopes, about which more later. These controls are continuously variable and range from High to Low, with lines to aid setting recall but no other values shown. The third rotary control turns an 11‑position output gain switch, which ranges from 0‑22 dB.

Nestling between the four threshold controls is a Link Off switch, its position reflecting the fact that it affects both channels. This toggles the Governor between stereo and dual‑mono modes: when linked, the lower channel is controlled by the upper control set, with the exception of the side‑chain filter frequency and output level selection, which must be set manually.

The centre section’s black background makes the two channels’ trio of horizontal meters easy to see. Within each trio, the upper two meters (GR1 and GR2) each show the amount of gain reduction (0 to 12 dB) being applied by one of the two slopes, whilst the third displays the output level (‑20 to +20 dBu) with a VU‑like ballistic and includes a true peak hold indicator. To the right of the meters is a pair of rotary switches that set each channel’s side‑chain high‑pass filter (off, 40, 70, 180 or 250 Hz) or select an external side‑chain signal, which is connected using the dedicated quarter‑inch jack inputs on the rear.

The metering shows both the output level and the gain reduction being delivered by each slope.

The right‑hand section carries, for each channel, a compressor in/bypass toggle switch and the two six‑position rotary switches that are used to select the attack and release times. The attack times are named rather than numbered, with a programme‑dependent Auto setting followed by Fastest, Faster, Fast, Slow and Slowest, but the timings are given in the manual (6, 8, 10, 15 and 40 ms respectively). There’s no auto setting for the release, and this allows an additional Slower position to be inserted, giving you a choice of 80, 100, 200, 450, 600 and 750 ms. A final control is one that’s always good to see on a front panel these days: the power on/off toggle switch.

Each channel has an electronically balanced input and a transformer‑balanced output, these being presented on XLR connectors on the rear along with the side‑chain input jacks, a ground‑lift switch and a fused and switched IEC mains power inlet that can accept 110 or 230 Volts AC.

There’s a quarter‑inch jack side‑chain input for each channel, and this can be selected using a control on the front.

Internally, the Governor displays a very high quality of design, construction and attention to detail, and the compressor circuitry occupies three PCBs that sit behind the Governor’s front panel. After the toroidal mains transformer in its screening...