“There is not much more to say about the Grelle Forelle. The club’s reputation as an institution in the field of electronic music now reaches far beyond the borders of the country and is also internationally regarded as a statement for the highest quality club atmosphere.”
— Wolfgang Sauter
The Grelle Forelle sound concept was formed lying in a hammock during a holiday in Croatia. I was relaxed and had time to think through the sound and acoustic concept for the Grelle Forelle. The sound system consists of two vertical bass lines each with four Lambda Labs DW-15 subs and one Alcons Audio QR36 line array speakers with Pro-Ribbon technology. For the technicians: This creates half-space conditions. For the non-technicians: This leaves no unwanted reflections of any kind from floor, ceiling or rear wall. For all visitors and fans of the Forelle: One of the main reasons why the Forelle sound is so special.
The System is rounded off by a 4-point setup with two additional QR36 framing the dancefloor. And of course this isn’t a simple 4-point setup – that would be too easy. Accordingly, the rear speakers are controlled in such a way that you “enter” the sound space from the bar, only to be completely surrounded by sound after only a few meters.
From the bar onwards, two Alcons Audio VR12 systems complement the front system and provide sound to the rear of the 30-metre long clubroom. Due to the concept of vertical bass lines, we have a clean bass impulse in the Forelle, which extends throughout the entire room and also provides a solid foundation in the lounge area behind the bar, precisely and without resonance. But of course, this would not be possible without appropriate acoustic measures. Therefore, we installed a multi-layered, 60cm deep bass trap consisting of porous absorbers, air volumes and custom-built membrane absorber elements in the entire area of the club’s rear wall. This was necessary to avoid any reflections of the highly directional bass reproduction from the rear wall, as these would have generated a lot of interference and would have disturbed the bass reproduction, which seems so ‘natural’, over the entire wall of the clubroom.
After the club management decided to increase the number of live concerts, the existing sound system was supplemented with three Alcons Audio RR12 tops on each side, which are hung to the left and right of the stage, which is then set up on the dance floor for live concerts. There were no changes to the bass system itself for this purpose, except that we adapted its characteristics, tuning, and transferring the frequencies to the tops for the requirements of live setups. This means that all musicians play in front of the bass system. And yes, it works without any feedback problems. Why? Because the vertical bass lines form a uniform and coherent wavefront and the microphones, therefore “sees” only a small section of the overall system.