to the comments above, my 2 cents
-- i believe the notion that even demanding affluent audiophiles need to spend as much on a streamer as they do a dac or pre or power amp is obsolete, based on new offerings appearing in the marketplace
-- putting a fiber converter before your streamer or dac can be beneficial but quality of implementation really matters.... cheap commodity converters with smps power create their own noise pollution and different fiber media converters can degrade sound (try a finisar pair versus trendnet or a no name pair!), best stick with good value audiophile products like sonore lhy etc etc
-- smart money in this space tries the higher value streaming solutions, then critically compares these to vastly more pricey alternatives on a returnable basis (dealer demos, used purchase, money back trials etc etc)... then be honest about whether you can truly hear the difference... we all know way too many of us listen with our wallets not our ears

