If you're interested, here's some critical feedback from a Marine who knows the sounds first-hand. Listen to some of the real explosion recordings and you'll find that like Hollywood gun sounds, it's too deep and rolls in too slow. If that's what you're going for, it's good, but real explosions are effective because of the shockwave. That shockwave means a VERY powerful and sudden wave of energy that sounds more like a crack that hits quickly and rolls off rapidly too. That also affects the echos.