GL4 is a dual function live mixer, allowing it to work in front-of-house, monitoring or combined roles. It also provides extensive facilities for live or studio recording. This great flexibility, coupled with a high ‘bang for buck’ feature set, made it a popular choice for PA rental companies and multi-function venues. The GL4 design was enhanced and upgraded to the GL4000 in the second half of 1996.
GL4 main image


  • Dual functionality. GRP/Aux mode switches reverse aux faders with the group and L&R faders giving up to 10 monitor sends with inserts on 100mm faders. A Centre Mode switch converts the 100mm C fader to engineer’s listen wedge control with insert
  • Formats: 24, 32 or 40 channels – either all mono or with 8 stereo channels. Was also available part-loaded. Meterbridges were optional
  • 8 Audio groups. Assigned from paired routing buttons and pan from channels. Groups access LR & M busses and have XLR outputs with insert. Groups have 3 segment led pre-fade meters and 12 segment, 3 colour peak reading meter access, plus VU meters if meterbridge is fitted
  • 10 auxiliaries switchable pre/post fade in blocks: 1-4, 5-8, 9-10
  • Left, Right and Mono busses. Available from channels and groups. LR & M have 12 segment, 3 colour peak reading meter access plus VU meters if meterbridge is fitted. GL4 also includes secondary L&R output with level and pre/post fader select on TRS jacks (can swap with the aux 9-10 XLR outs with inserts)
  • 11×2 Matrix. Fed from the groups and the LR & M busses
  • 8 Mute groups. 8 master mute group buttons with single / multi mode and preview facility. Input channels, auxes, groups and LRM sections all have mute buttons
  • 4 band EQ plus HPF. Separate controls for sweep and cut/boost on all sections. HPF is swept from off-20-400 Hz
  • Stereo channels. GL4 could be ordered with blocks of 8 stereo channels, each with individual gain input stages for left and right sources
  • PAFL system. Stereo PFL with trim
  • Talkback. Talk to LRM, groups and auxes. Trim control for mic
  • Lamps. 2 BNC lamp sockets are provided
  • PSU. The GL4 was supplied with a RPS10 rack mounting (3U) linear power supply. A backup RPS10 could be linked via an RPSD power supply combiner and auto-switcher