So we've recently upgraded to an AV receiver for better sound with our new Samsung smart TV, but we kept our old Sony DVD player and 20-30 year old speakers. We've got the Sony hooked up to the AV receiver correctly because there's picture on the TV. The speakers though only work through the Sony; we can have it turned to the max and it doesn't change a thing. We do have sound that comes up to a reasonable rate but we'd like it a very good but louder. The AV is also hooked up to a new sub woofer and thats working correctly too.
Will we have to get a new speaker system and/or a new dvd player to get it playing through the AV?
The correct way to hook up surround equipment is: Components (including your DVD player) ------> Receiver -----> TV.
If you are forced to hookup DVD to TV directly because the new Receiver doesn't have the same connection as DVD, then you must add another audio-only connection from DVD ---> Receiver. Sometimes you don't have to add this extra connection if BOTH TV and Receiver are ARC-capable.