Agree with roberjerman, any bridged amp should not be used with a speaker having an impedance of less than 8 ohms.
Adcom GFA 555 II
Any advice on running a pair of Adcom GFA 555 ii bridged with Magnepan MG/12QR i am currently using one and was considering picking up a 2nd one, are there any benefits? can they handle the 4 ohm load bridged as i’m sure when pushed they dip pretty low in ohm’s or is this a bad idea?