I would have to agree with silversurfer. The 170s sound pretty even handed and clean across their range. One thing that may be in their favor is that they don't go quite so low, and that narrower operating range is a design choice. The way I see it, the aerogel driver was chosen (or designed) because of its excellent midrange capability, and the trade off is less bass. Rather than try to tune a cabinet lower to get some additional bass that would end up being less than optimum, the design focused on midrange clarity.