mkaay... So the difference between versions every time is recompiled components (the components are mostly open source) (and you can pick the version where the open source components are recompiled to the max CPU instruction set extension supported) and removed components vs the org installation...
In which case unless each version includes source changes to components (either proprietary (unlikely and probably not good), or from the component vendors), he's just shuffling components and settings around.
Provided whatever code the components have can take advantage of the SSE superset, the version optimized for the particular SSE set may be faster than a generic compiled version probably bundled with foobar. Note the provided. The speedup can only be determined by profiling the components and testing empirically what the speedup is.
I still don't understand why the developer doesn't just provide a chagelog. It + using bs terms like stellar sound quality and every version apparently having inevitably better sound quality makes it look like one big joke.
Generally it would seem like removing components like CDDA makes no sense whatsoever. Yes they're loaded into memory when foobar starts, but no, no code is executed until you play a CDDA (CD) file
... This really is getting a bit absurd.
His latency argument is not at all convincing. Whatever he claims, for vanilla foobar, output data is buffered before it's sent to the DAC (FLAC decodes at about 30-90x real time speed on modern PCs, so keeping the buffer full is not a big deal), as mentioned above, so there is no difference in latency or jitter or whatever else... Unless he'd like to provide some measurements claiming otherwise or a theoretical explanation to refute the above and earlier stated...
> So in short: try it, if it does not sound any different (or maybe even worse for your taste) then leave it, simple as that.
I'd much rather prefer - if you can A/BX between vanilla foobar and 'hd', or can post some RMAA measurements on the output (and this applies to fidelizer too) then post here, otherwise, any deliberations of 'omgbbq it sounds better and different' will always be viewed with a pretty high amount of skepticism at least from some of us, comparing the coathanger cord to the expensive one, or two kettle leads thinking one is a $300 one
(yes, delicious mind playing tricks on you).