For reasons that are not always clear, pro-audio products often fail to meet the sonic requirements of audiophiles. Daniel Weiss, a highly respected pro-audio engineer, has not only succeeded in doing so, but has exceeded all expectations. His two DACs, the 501 and 502, are masterfully engineered and sound superb. The two WEISS models are sonically identical, differing only in the size of the chasse (the 501 is half-sized, the 502 full sized), and in that the 502 has an additional balanced headphone jack on the rear panel. Both sound great and produce incredible performance for their price. If these were only DACs they would they would be at the top of their game, but they are much more.They are Roon-ready, have an excellent headphone amp, as well as some features rarely seen at any price point including a “de-esser” for bright/sibilant recordings, as well as room equalization and tone control. The 501 and 502 have been highly praised by both reviewers and customers.