Roamy here. Huntsville used to be the town where you could hear rocket engines roar, and IIRC we still hold the record for the loudest sound ever recorded, one of the engines for the Saturn V without water sound suppression. It chipped concrete in the test area. Now most of the engine testing is performed at Stennis Space Center, including the J-2X engine. This was a “burp” test, a baby step on the way to a full eight-minute engine test.
This test was actually a couple of seconds shorter than planned because of higher than expected pressures in the combustion chamber. Really nice coverage of this test and what the engineers learned from it at the J-2X blog.
Test what you fly, fly what you test.
Author’s note: Tried embedding the video, and for some reason, it won’t cooperate.
[XBrad- Let’s see if that works.]