If you stream music from the internet, I can't recommend this more highly


I had been using a Roon Nucleus to stream Qobuz, with my Chord Qutest directly connected to the Nucleus. I thought I was getting pretty decent sound quality. And then I got a marketing email from Small Green Computer touting some of their optical gear. The basic idea is that normal cables and connections used to stream from the internet pick up noise of one kind or another (radio frequencies and electromagnetic something or other). But fiber optic cables and their connections/interfaces do not. I don’t know anything about anything, but it made theoretical sense to me, it wasn’t a huge amount of money ($1,400), and with a 30 day return policy I figured I could always return it if I didn’t hear any improvement. Well, I didn’t just hear a slight improvement; it was like turning on the lights in a dark room. Much greater clarity and detail, much better micro and macro dynamics, better timbre to acoustic instruments -- overall just more lifelike. Two quick examples: I’ve listened to some of Steely Dan’s top songs 100s of times over the course of my life, and this is the first time I’d ever noticed a particular and very subtle sound characteristic of Fagen’s keyboard in Babylon Sister. It’s hard to describe, but it’s like there’s a slight sound of air being exhaled by it. The other example: the specific timbre of whatever percussive instrument is used at the beginning of Copeland’s "Fanfare for the Common Man" (a recording by the Minnesota Orchestra). There’s more of a metallic sound than a drum skin sound to it that I didn’t know was there before. The metallic sound starts in the center and then projects out and to the sides, like a wave washing over you. Anyway, I’m just thrilled about having stumbled upon the whole "optical" thing and felt obligated to let others know about it. If you stream music over the internet, I highly recommend giving it a try. (The product I got was the opticalRendu, with the linear power supply option, and the Fiber Ethernet Converter Bundle option.)
128x128hiphiphan
this is true, but at the same time empirical study cannot exist without a theory, these two things are tied. given a theory, you may verify it empirically if you are unable to prove its soundness theoretically. in physics, this is a common practice, and also in computer science. for example, if a constructed by you mathematical model/theory/algorithm cannot be proved (theoretically) to be good (i.e., be objective, realistic, or
optimal or sub-optimal), you carry our an empirical  study. In  computer science, this involves computational experiments that somehow show  the practical behavior of a given algorithm. pretty similar scenario is in audio stuff where your estimation is based on auditioning
(these are your experiments). but here auditioning experience itself is subjective, unlike physics and computer science, for example, where the experimental results do reflect an "objective reality". in audio world an "objective reality" is subjective, it depends on our taste, mood, current environment etc. 
niodari
... empirical study cannot exist without a theory ...
Actually, by definition, "empirical" means in the absence of theory. (See definition two posts previous.) Of course, I think empirical observations are most useful when coupled with theory, but the two are not inherently linked. That's something that just bugs the heck out of the measurementalists here.
What part of "empirical" evidence, from a scientific standpoint, requires controlled listening tests, not ad-hoc listening tests hence anecdotal evidence is hard for the kids in the back to understand??
@audio2design 
What part of "empirical" evidence, from a scientific standpoint, requires controlled listening tests, not ad-hoc listening tests hence anecdotal evidence is hard for the kids in the back to understand??
The answer is "none."  Empirical simply means "verifiable by observation or experience."  Whether the observation or experience results from an orderly, documented, scientific, study, or simply a few dudes sitting around smoking a doob and listening to their favorite tunes....the difference is simply methodology - both are examples of obtaining "empirical evidence."  An empirical study can be performed to verify a theory, and empirical evidence can also be obtained to verify a correlation with measurements, but you can have measurements and/or a theory without empirical evidence.  Empirical evidence is obtained every time you listen to your system.  I think you are all sort of making the same point. 
Empirical evidence can also be anecdotal evidence and persons postulating on how much difference a cable makes in the sound coming from their speakers is empirical and anecdotal evidence. From this evidence we build hypotheses is the difference because of the cable or some other factor? Now we can begin to form experiments to understand why this person hears differences between cables or we can just take their word for it only one of these will further our knowledge of cables and human perception and it isn't the latter.