Summary: Really disappointed about Mackie. I guess this it's always true that "if it seems too good to be true, it probably is". When I read the specs I thought it was a great price for a 400W Mackie, even lower price than some Behringer's so, the purchase seemed like a no-brainer. However, the 400W it's a joke, a 100W Peavey guitar amplifier is louder than this speaker and it's not even designed for voice applications.
Summary: Quit working after 6 months. No power. These things were not worked very hard. They sound ok but, now I have trust issues. This will be the last Mackie product I will buy. Engineered in USA. Built in China.
Summary: This thing craped out after 9 months use as my electronic drum monitor... Never moved or left home... I own an old pair Mackie srm 450s that still sound great after hundreds of gigs... Buy this Thump series at your own risk!
Summary: Not super loud (their SRM-450 is much louder), but great sound quality. I adored this speaker, right up until until it broke. I was running it hard on a hot day and the internal amplifier blew, despite all of the advertised protection features. One year warrantee and terrible customer service on the phone (long hold times for service, multiple transfers, parts department isn't answering their phone).
Summary: I got this dude slightly used and so far so good. It is well built and it comes with a good lengthy power supply. For a second hand powered speaker, I think the Mackie Thump-12A 400-Watt have met my expectations. If you are a dj, small church or need something for a small group reheasal, etc, this speaker will help alleviate your sound requirements.
Summary: I haven't had any issues with reliability, as such, but to call these "400 watts" is a joke. At line level, you can barely hear anything, and even using a mixer to boost the signal: not loud enough to complete with even the tamest of drummers. I had heard great things about mackie powered monitors, but I guess they don't make them like they used to. I regret the purchase, I should've waited longer to find something used that packed a punch.