Try the brand new GR Bass AeroTech Full Carbon dedicated Combo, not cheap for sure, but lightweight at 8.8 kilos (hard to find lighter and so powerful).   https://www.thomann.de/gb/gr_bass_at_cube_acoustic.htm   There's also the Acus For Bass model, but it will be heavier at 13 kilos and a little cheaper.   https://www.thomann.de/gb/acus_one_for_bass_wood.htm   And there's the Schertler Unico X at 16.8 kilos, but you'll have to rob the bank.   ht