Quad ESL front grill
Many people think that the Quad ESL sounds better without the metal front cover (and I agree).The image below shows the effect of the metal front grill. To show the irregular behavior of the grill it's effect was measured in two different positions (the first in the exact position it should be in and the second one inch higher). Both were positioned at a realistic distance of the treble panel.
It must be said that on an audibility scale the effect is not as bad as it looks.
