Is a femto clock important if you aren't using asynch USB?

While it is true that USB does not rely upon the streamers clock, it seems to me that you want a good DAC clock for stable sampling of any input.

Seems?

What you really should want is a modern DAC instead of worrying about clocks.

I like buying used but never do it with Digital gear.    I did buy a R2R DAC ,  but I also have a DAC that can do DSD.     When I bought my streamer I wanted the latest tech and codecs.     I am a late adopter when it comes to everything else.....

Some DACs like my RME adi2 always use their internal clock regardless of input type.   It's Femto clock is used also when there is a Coax or Tos. Input,  it doesn't just use it's clock for USB.

The better the internal clock, the lower the DAC's jitter rejection can work, to a point.  If upstream jitter is extreme enough no internal clock will fix it.

I agree though that chasing a 10 year old DAC seems imprudent. That was just after the cut-off range, when I remember Redbook playback getting much better.