Iād agree Majik and thatās what we do but it all depends what amps etc. you are using. I still see plenty of bands micāing amps even today so itās still pretty common.
To a degree if heās using the bose and youāre using an amp that sort of explains why you are getting lost in the mix a bit (even from your own perspective). I suspect heās got a one man band setup which he uses all the time and of course youāre just joining him for the odd song. If you are doing a longer set it would be a good idea to see if you could both utilise that Bose BUT even better would be - as Majik says - if heās got a little mixer that you could all plug into and then go into one of the channels of the Boseā¦that would be the preferred approach as itās easier to adjust your mix etc. Iād be gob smacked if he doesnāt have a mixer.