Thanks for taking the time to read my questions. I have several .wma and .mp3 files I've copied from the original CDs to my HDD. After moving 3 times in 2 years, I've lost a few of the originals (and yes, these are on I PAID FOR) was wondering how to go from HDD back to the closet original format, which I'm assuming is the .cda or .cdda file format and that it has the highest quality and is the best way to go. So, basically I'm wanting to know what is the best file format to give me highest sound quality. Does the .cda file format/encoder have it the best? If not, which one does. Also, I have Nero Ultra Edition 6.3, CD Architect, SoundForge, and a friend has some Steinberg? program. I have used Nero before and have fooled around a little w/SoundForge. What's the difference b/w say CD Architect and SoundForge and will/should I use programs like SoundForge and Steinberg to achieve the best sound quality? I've read some things about PCM (which I'm still not sure what it is), AC3, which from my understanding is the old name for Dolby Digital and is similar to DTS. I'm assuming that these sound formats have to do strictly with DVDs and not CDs, is this correct? Any help you could provide would be greatly appreciated and sorry if any of the questions sound ridiculous.