A pre/pro does not have 2 channel bypass (unless you mean it is bypassing any processing within the pre/pro, which is what I will assume you are refering to).
I may be mistaken on this, but I have not seen many pre/pos that don't offer the compatible single ended input along with the balanced input for running pure 2-channel audio (without any internal processing in the pre/pro). I have owned a couple pre/pro (Krell HTS 7.1, McIntosh MX 132, etc. . .) and while all of these have balanced inputs for this, I believe they also have single ended input.
Does you Apogee minidac accept more than one digital input? If so, you could take the analog signal from your CD player into this and then from that DAC to the pre/pro via the balanced (assuming it doesn't have the single ended input option for pure analog). For movies, you would simply run the digital signal from the CD/DVD player into the DVD input on your pre/pro for surround processing.
Will the adapters affect sound? I suspect not. I would say one would need to have an extremely revealing system to be able to identify when they are being used vs. not being used. We are talking about a huge bucks system.
I may be mistaken on this, but I have not seen many pre/pos that don't offer the compatible single ended input along with the balanced input for running pure 2-channel audio (without any internal processing in the pre/pro). I have owned a couple pre/pro (Krell HTS 7.1, McIntosh MX 132, etc. . .) and while all of these have balanced inputs for this, I believe they also have single ended input.
Does you Apogee minidac accept more than one digital input? If so, you could take the analog signal from your CD player into this and then from that DAC to the pre/pro via the balanced (assuming it doesn't have the single ended input option for pure analog). For movies, you would simply run the digital signal from the CD/DVD player into the DVD input on your pre/pro for surround processing.
Will the adapters affect sound? I suspect not. I would say one would need to have an extremely revealing system to be able to identify when they are being used vs. not being used. We are talking about a huge bucks system.