Not quite, the very first silencer, the tiny one after the cat, does very little. I removed mine and it made no difference to the exhaust sound at all. the one that matters is the next one, the first of 2 transverse silencers at the rear.
One thing I did notice was then when my backbox came loose, deleting the tiny first silence added a rasp. my backbox had a habit of coming loose untill I changed the washers and before removing this silencer it didn't make much difference when it was loose, after removing the silencer it would start rasping (nicely). Since then going to a Biscione Racing backbox I now have the rasp all the time but the shape of the backbox outlet makes it too deep and loud at idle.
Alfa GT 3.2 V6 - Daily Driver.
Alfa 145 QV ph1 in green (Death by rust project) For Sale.
Alfa GTV TS ph2 in blue