I’m a vintage dealer and have had several model 19s in the past. It’s one of those speakers that straddles the efficiency and not so eficient fence. The model 19’s woofer does need a certain amount of power to come to life but a solid state amp will sound horrible with the horn section. Your best bet is a higher powered push/pull tube amp in the 50-100 watt range. Both Quicksilver & Jolida have nice sounding products in that range as does Atmosphere. SETs would normally be my first recommendation with vintage horns but in this case aren't going to do it for Model 19's woofer.
david
david