I believe you've found the exact piece of equipment I would need for my CD player, and the cost is reasonable. I already have a good preamplifier to power my active loudspeakers, so I could connect the miniDSP Flex to the preamp for listening with headphones. Or I could also invest in a headphone amp as you suggest. Headphone amps with great specs are not expensive, these days. I appreciate your help!And also less parametric EQ options than the miniDSP Flex. Granted you have to buy a headphone amp to connect to the miniDSP Flex, but that's still less money than RME ADI 2. And miniDSP Flex also has optical input (TOSLINK) from the CD Player.