Trump is building (has built?) a protectionist wall around the USA.
The trouble is, the USA has changed its economy to a global dependent structure - everything is dependent to a greater or lesser degree on imports.
And he has implemented the wall overnight, where shifting manufacturing, building revamping facilities/factories takes time, typically years.
So now we will have the USA market and the world market - and they won't be the same.
Companies and product design structures based on a global marketplace, will now need to be revised.
Sound United will need to look closely at its manufacturing facilities and brands, and match those to the marketplaces (US / Rest of world).
Although in theory, the Tariffs should not impact on exports - and US based manufacturing should be able to export, reality is, reciprocal tariffs are likely to be deployed by all nations that punitive tariffs have been applied to.... so not only will it kill imports it will also kill exports - USA close the doors and windows, and decides the rest of the world does not exist.
In previous generations, Marantz was USA, and Denon was Japan.... perhaps they can survive as USA manufactured Marantz and "Rest of World" manufactured Denon....(and similarly with the rest of the SU suite of companies)