 Technically , it is known as a speaker that easily reveals poor quality in recordings . Recording engineers sought to dull its treble response by hanging tissue paper in front of it , resulting in what became known as the " tissue paper effect " , a type of comb filtering . The NS @-@ 10 has been used to monitor a large number of successful recordings by numerous artists , leading Gizmodo to refer to it as " the most important loudspeaker you never heard of " . Yamaha discontinued the product in 2001 . 
