Back to amps, we've now at least three tiers of relatively inexpensive modules that are demonstrably transparent, which at the analog end of the processing chain is sufficient (for now): #1 Purifi, #2 Hypex, and #3 ICEPower. I suspect some of Texas Instruments' PurePath HD modules may comprise a fourth tier, but we've not seen any (?) of those independently analysed here. Benchmark's amp may beat them all - I'd have to go back and look to verify that. However, I didn't include it as they're not a ready made solution that can dropped into a case by the average DIYer.