Hi Shak - I've heard both. Personally I went with the F113. But I could have easily been happy with the DD18. There's no bad decision here.
Since the performance of a sub is very room dependent, it's a bit difficult for me to say exactly how the two subs differ in sound quality. Both are powerful, fast, deep, and tuneful. The F113 may be a touch faster, and the DD18 might be a touch deeper, but I could be wrong about that. If I'm right, then I would also say that the F113 might be a slightly better choice for music, while the DD18 might be a slightly better choice for movies. But others may have a different opinion.
One significant difference between the two subs is that the DD18 has an 8 band digital EQ and the F113 has only a single filter for reducing the room's primary bass mode. IMO, digital EQ is virtually essential to good sub performance, so if you don't have a plan in mind for adding digital EQ to the F113, I would go with the DD18. When I was making a decision about which to buy, I already had a digital EQ in the system, so I didn't need to choose on that basis.
Good luck.
Bryon
Since the performance of a sub is very room dependent, it's a bit difficult for me to say exactly how the two subs differ in sound quality. Both are powerful, fast, deep, and tuneful. The F113 may be a touch faster, and the DD18 might be a touch deeper, but I could be wrong about that. If I'm right, then I would also say that the F113 might be a slightly better choice for music, while the DD18 might be a slightly better choice for movies. But others may have a different opinion.
One significant difference between the two subs is that the DD18 has an 8 band digital EQ and the F113 has only a single filter for reducing the room's primary bass mode. IMO, digital EQ is virtually essential to good sub performance, so if you don't have a plan in mind for adding digital EQ to the F113, I would go with the DD18. When I was making a decision about which to buy, I already had a digital EQ in the system, so I didn't need to choose on that basis.
Good luck.
Bryon