@ruleof72
You said " I’m definitely open to other suggestions." so I’m going out on a limb here with another suggestion. I am not disparaging anyone’s choice on a DAC this is addressed to the OP. You mention non analytical DAC then describe your system having a NAD integrated. The NAD is fairly analytical which to me means it reproduces what is fed to it as accurately as possible. If you decide to keep a fairly precise SS amp then the products mentioned so far would probably meet your expectations. On the other hand if you move to a tube system the idea of adding a tube DAC or other tube sounding DAC just adds more coloration to the tube amps. In my opinion in order to get the "flavor" of your tube preamps or amps it makes more sense to go with as neutral a DAC as possible. The more precise the DAC at conveying the signal without adding or taking away in other words analytical would give you a much better idea at what the tubes offer in your tube components. So far I have seen 1 DAC mentioned the Benchmark and it is a pretty neutral DAC. There are others that would qualify as neutral pretty much any modern Delta Sigma DAC.
You said " I’m definitely open to other suggestions." so I’m going out on a limb here with another suggestion. I am not disparaging anyone’s choice on a DAC this is addressed to the OP. You mention non analytical DAC then describe your system having a NAD integrated. The NAD is fairly analytical which to me means it reproduces what is fed to it as accurately as possible. If you decide to keep a fairly precise SS amp then the products mentioned so far would probably meet your expectations. On the other hand if you move to a tube system the idea of adding a tube DAC or other tube sounding DAC just adds more coloration to the tube amps. In my opinion in order to get the "flavor" of your tube preamps or amps it makes more sense to go with as neutral a DAC as possible. The more precise the DAC at conveying the signal without adding or taking away in other words analytical would give you a much better idea at what the tubes offer in your tube components. So far I have seen 1 DAC mentioned the Benchmark and it is a pretty neutral DAC. There are others that would qualify as neutral pretty much any modern Delta Sigma DAC.