by Hugh Robjohns » Fri Jun 01, 2018 7:47 pm
The Beeb certainly designated different designs as grade 1 or grade 2 monitors. Grade 1 was supposed to be a necessity when assessing the placing of mics, for mixing, and for quality assessment, while grade 2 speakers could be used in less critical roles (eg, production monitoring)
However the LS3 and LS5 terms originally denoted the speaker's intended application. LS3 speakers were for use in OB trucks and small edit-suites where space was restricted, while the much larger LS5 speakers were for studio control rooms and studio floors.
There were several cases where the same basic design was designated with both LS3 and LS5 numbers, because their physical form or finish was optimised for OB or studio use. For example, the LS5/1 was the studio version of the LS3/1. The 3/1 had the (dual) tweeters mounted in front of the woofer and the cabinet was painted in Hammerite grey, while the 5/1 used the same drivers, but placed vertically one above the other on the larger baffle, and had a veneered cabinet. Similarly, the LS5/11 and LS3/4c are closely related ceiling corner speakers for studio (VT suites, mostly) and OB truck applications.
As it happens, the LS5/8 was indeed a grade 1 (as was the 5/11), while the LS3/5 (and 3/4c) were grade 2s, which may be where the confusion comes from... although, even more confusingly, the numbering policy got a bit muddled in the later years when all OB and studio designs were lumped together under the LS5 designation, including the Beeb's final two in-house models, the 5/9 and 5/12.
H
