Amarra for iTunes at RMAF...

I don't buy the bios burn in at all. Doesn't mean it's not true, just means I don't believe it. I know there is a lot of non-sense non-science as it relates to audio and I think the BIOS "burn in" lends itself to that camp :)

Sidssp, sometimes it is just a matter of selecting them in iTunes and telling it to convert them to Apple Lossless and you are done. I had the same problem, IIRC, with Apple Lossless files in another context, and that cured it.

The BIOS burn in comments I was referring to have been made by guys making CMP PCs, and their claim is that to assess a BIOS change you need to make the change and then let it burn in.

What does CMP stand for? Cellular multi-processing?

When you say "assess a BIOS change," do you (they) mean verifying that the revised BIOS firmware functions reliably, as components age, temperature changes, etc.? Which makes perfect sense.

Or do you (they) mean that the effects of the BIOS update on the sound quality of audio being processed by that pc will change during that burn-in period? Which I can tell you, as an experienced digital and analog circuit designer, and also as an audiophile who considers himself to be open-minded, makes no sense whatsoever. And would probably represent failure of those people to recognize and control extraneous variables, which are innumerable when it comes to computers. For starters, just consider all of the operating system files which are constantly changing, disks that are constantly fragmenting, asynchronous background processes whose timing relative to one another is constantly changing in both hardware and software, etc., etc.

And if they meant the latter, did they verify their observations by re-flashing to the earlier BIOS, letting it burn in, then re-flashing to the later BIOS, burning in again, and seeing that their findings were consistent across multiple trials?

Regards,
-- Al

Almarg, I suggest you look up Cic's Music Player and www.audioasylum.com for the discussions there. CMP, amongst other things, is a shell that automatically turns off a lot of unnecessary services in XP. It then works with cPlay to play music files. I think most people that have researched leading edge computer audio have come across it, and it has a significant following.

Yes the claims were that BIOS changes affect audio performance. And further, some claim that BIOS changes have a burn in period. Being open-minded you might be able to follow their drift. I doubt you have a monopoly in relevant tecnical expertise amongst the CMP community, so you may learn something from the interaction.

Unlike many other theories in digital audio, the CMP theory is to use an under clocked machine with as many services turned off as possible (amongst other things). Therefore turning things off in BIOS aids that. This isn't my claim, so I am not the best one to defend it against your scepticism. But the work done by many on testing configuration changes on CMP performance seems to have at least some validity given the intelligent following it has. Therefore I remain open-minded rather than dismissive of burn in of a BIOS change. No matter what we think we know about something, it is only a model in our heads, and it is an abstraction of reality - not a substitute for trying it to see.

Personally, I built a CMP/cPlay spec PC and it sounded good, but the current Mac configuration I have sounds better to me. I never played with variations of CMP, but with the Mac I got to the opposite conclusion, which is that a powerful Mac with lots of RAM sounded better than a minimally powered one. I suspect the CMP guys may just prefer less power/ram etc in order to reduce power supply size (and therefore noise) and to reduce heat (and therefore mechanical and electrical noise from cooling), but you would be better to ask them that one.

I left the BIOS argument alone, some things in audio are so far flung I just opt to stay away, but I would like to report that I have decided to purchase the Amarra software. After careful listening sessions I am convinced (well 95% convinced and that's good enough for govt work) that it does in fact offer tangible results as it relates to creating a more-real musical presentation.