Hello, I am new to the forum. I have a pair of first generation JM Lab Grande Utopia's manufactured in 1998. I read in an early review that the only tone control for them is a jumper wire located behind the access plate on the back of the upper 11" woofer box. Focal no longer has even an electronic version of speaker manual and the North American distributor does not know which position of the jumper is the +1 dB position and which is the 0 dB position. Can anyone help?