I may be wrong here but I think early 44's had either a 5V output (from a pair of phono sockets) or a 500mV output (from a Din socket). There was a modification on later models to add a 1.6V output on an additional pair of phono sockets.
The Beolabs expect a nominal 1V input (I believe) at the input phono socket.
Obviously the 5V output is far too hot - if you have the 1.6V output you can experiment (but be careful with the volume control). The 500mV output will worth but the volume control may be higher than you would have used it in the past.
Generally speaking, you aren't learning much if your lips are moving.