Thanks all for the interesting SoX incantations. I really appreciate it.
I'm certainly not the OP (134 pages into this thread!) but I'm the OP on this mini sub-thread I guess. Let me kindly restate my purpose:
I am not a fan of ABX tests where someone does a series and gets fail-fail-fail. I have seen many many such logs online and they leave me cold. This is just my perspective. Because it begs the question whether the tester has good enough ears, good enough transducers etc. IMO you have to pass something first, and then gradually dial up the difficulty until you fail.
So my purpose here is to do something relatively pure - you'll notice I converted the 24 bit myself rather than relying on the HD tracks 16 bit version, since you don't know how that was done. But after that, give 24 bit every chance to win. Look at the results as you go. Crank the volume on soft passages. Listen to a very short clip over and over. Everything other than looking at the electronic signature. I know you consider this "cheating" but it is not. If your ears can detect it, fair game. I'm not trying to reproduce "natural listening" in my first pass. I promise once I get a pass I'll start to dial back on these things. Then people who view the logs can make their own decision whether it matters to them.
Please realize I fully understand the mathematics behind dither, normalization, sampling, FIR filters, and all kinds of other semi-useless information.
None of your comments are invalid, I'm just saying not yet. I am still struggling to see the magic 5% first.
Which me luck! I hope to try again later today. I also set up and converted some Linn tracks yesterday. I encourage anyone interested to try to reproduce. All the tracks and software I'm using is 100% free. If anyone has a different passage or track that passes for them please let me know.