In the past, analog op amps displayed inferior performance compared to an array of discrete transistors, especially at the input stage of a mic pre where low noise and distortion plus matching between the input’s plus and minus signals is so important. Thus, historically, a discrete mic pre has been higher quality than a “chip-based” mic pre.
Apogee’s Advanced Stepped Gain mic pre uses the architecture that many discrete mic pres use, but use the latest in modern op-amp tech for the actual gain stages. These op-amps will generally perform BETTER than a discrete front end. There is no reason for us to use discrete transistors for our mic pres.
This is borne out by the fact that our mic pre specifications (gain range, noise level) are still superior than any other all-in-one interface out there.