EJ3, I think you'd probably get a better response posting a separate thread exposing your question to a wider audience.
What I can say about the SHD in relation to how it could help you, is that with it's digital output iit could be a DAC and ADC for all your analog to digital and vise versa recording, and give you room correction in your stereo system. I probably recommend however something better suited to your process and that would be the ADI-2 Pro FS R Black Edition. 2-Channel high-end AD/DA Converter. There are cheaper options, but the RME is superlative in this aspect for the money.
Thank you for not being condescending and the advice on getting it out to a wider audience. I am relatively new to the computer scene in the USA, I left the USA in 2001 & lived in 3rd world cell phone and computer access conditions until the second half of 2018. Web sites like this, texting, streaming, heavy traffic (prior to 2001, where I lived in the USA you wouldn't see a car for 10 minutes to an hour at a time, so to me 5 cars at the same time is heavy traffic) where I live now (which is where I lived prior to 2001) are all new to me.
Yes, I was thinking that I need both a DAC & ADC in one package. I know that my oppo 205 has a very good DAC but it seems that for what I need to do a one box solution is a much better idea. At the moment I am not working and (while I have enough to live on for at least a year, I have to be careful with it and get back to working soon. But I can look at this selection and plan, which is primarily what I wanted. Thank You for Your Consideration.