Just to clear up any confusion...
"Mousetrap" and "The Front End" are one and the same thing, at least for
the moment (of which more anon). The new name was intended to make it more
comprehensible in the international market, but many people continue to
refer to it as "Mousetrap"! Ah, well...
The original Front End is still built to order. It is essentially a mono
device, but uses the vertical degree of freedom given by tracing a mono
groove with a stereo pickup. The first sidechain uses groove wall
selection and the other two are click blankers of differing flavours, for
use primarily with electric and acoustic recordings respectively. The unit
has its own pre-amplification and equalisation built-in, so that any
published recording curve can be properly compensated.
Since 1995, when the original was launched, the archive sound world has
changed, and thus there will shortly be a new Front End, with a stereo EQ
section and features more suited to today's requirements.