Jeff - the real advantage of a properly executed USB DAC (many are not) is that it eliminates the SPDIF step in the chain. As you get into this, you will discover that a lot of SPDIF cables and implementations are less then excellent and add an additional layer of grunge/noise to the signal.
IMHO moving from an electro-optical-mechanical transport to a hard drive is where the biggest quality gain comes from.
I run Toslink (optical) out to a DAC and it is excellent. Problem for the moment is that there are a limited range of choices for the mini-Toslink format. Good results with Toslink depend on having glass as opposed to fiber conductors.
There are huge numbers of nice DACs available here at every price point imaginable. (Not all take Toslink) The other choice would be to have Bolder Audio or RedWine Audio mod your Squeezebox. Dollars are certainly less or similar and many would argue that the results are superior then all but the very best DACs.
IMHO moving from an electro-optical-mechanical transport to a hard drive is where the biggest quality gain comes from.
I run Toslink (optical) out to a DAC and it is excellent. Problem for the moment is that there are a limited range of choices for the mini-Toslink format. Good results with Toslink depend on having glass as opposed to fiber conductors.
There are huge numbers of nice DACs available here at every price point imaginable. (Not all take Toslink) The other choice would be to have Bolder Audio or RedWine Audio mod your Squeezebox. Dollars are certainly less or similar and many would argue that the results are superior then all but the very best DACs.