Perhaps that's why I didn't pick up anything less than desirable when using the pop music CD. As to frequency in the low 20's, certain Enya songs or some cello pieces can hit that low as well. Yet it doesn't mean that the reduction in bass at just this level would make to the total bass package becomes unacceptable. I just don't want to make another trip with proper CDs to listen to it again. Now Stereophile did say, I think, that the Illusion projects plenty of bass for the organ piece, without rattling the wall however. It's just at the level of pricing, your expectation becomes much higher.