I'm converting a PAL DVD to NTSC format. I use DVD2AVI to rip the audio (as a AC3 file) and then use BeSweet/Ac3machine to adjust the "framerate" of the audio to 23.397fps and pump out a new AC3 file.

I am currently listening to it using stereo headphones attached to my PC. I have noticed that when I listen to the original AC3, it is very loud. But when I listen to the new AC3, it is very quiet. From what I've been reading here, the new "quiet" AC3 audio file should still sound just as loud as the original audio when played through a Dolby Digital 5.1 receiver. Is this correct?

So then why is the new AC3 so quiet when played through the headphones? I've tried using the "Boost" and "gain" options in Besweet or ac3machine, and I still can't get it as loud as the original AC3 file. In fact, using those functions seems to introduce some distortion to the sound. Also, will using gain/boost affect how the new AC3 sounds when played through a DD5.1 receiver in 5.1 mode?

To re-iterate:

1) Will the new, quieter AC3 file produced by Besweet sound as loud as the original when played on a 5.1 receiver in 5.1 mode? (assuming I use the same bitrate and all that and don't fiddle with normalization)

2) Will using the gain or boost functions affect how the AC3 file sounds when playing it through a 5.1 receiver? Or do they only affect the sound when it is downmixed for play on 2.0 or what not?

Thanks for reading.