The ESL-2905 is the largest of our full-range ESL models. It employs 8 electrostatic panels, the inner two utilising the concentric rings of anodes used to create the point source image. Whilst all electrodes receive the same music signal, each electrode area reacts slightly differently, such that treble frequencies appear to come from the centre of the speaker. This often leads to the belief that a crossover separates the signals, but this is not the case. The outer panels (three above and three below), are linear panels, the entire surface of each reacting in unison to the signal. The large overall surface area is necessary to provide deep bass extension and dynamic response. Construction is a combination of tensioned aluminium extrusions coupled to stainless steel support structures, with a piano gloss wooden trim. The substantial base construction is finished with piano gloss side cheeks and high-quality terminations. Internally, the highest quality components are used, including rare ccore transformers and high-grade audiophile capacitors. Three types of protection system are used to ensure the speakers are difficult to damage when over driven. A rigid three-dimensional structural support system, combined with an overall speaker mass of 41.6kg ensures the maximum transmission of sound energy. This results in the most dynamic and powerful Quad ESL ever produced.