I have a Stax Signature Lambda SR-404 (Normal edition) and a Stax SRM-252S Driver Unit, and I wanted to get a Tube component in the chain somewhere. This is where I realized I wasn't sure if I should upgrade the driver unit that has a tube in it, or upgrade just the dac with a tube in it, OR if I need tubes in both dac and driver unit. If so which and why??
Any insight is much appreciated