Using the Nero CD ripper, I get a bitrate of around 161 kbps VBR. If I use EAC and the Nero front end then I get a bitrate of around 179 kbps VBR. The differences are minimal but I cannot ABX between the 161kbps VBR mpeg-4 AAC and the source. Additionally, the 179kbps VBR AAC file is only 1.4MB smaller than the mp3 ripped with Lame 3.97b1 at -V 2 --vbr-new. The 161kbps VBR AAC is 2MB smaller than the mp3. So, how would I go about changing the command in EAC?
Again, thanks for your input at EAC is a much better ripper than Nero's or iTunes.
[a href="index.php?act=findpost&pid=340078"][{POST_SNAPBACK}][/a]
Hey kornchild2002, thanks for the feedback on EAC, I love it as a frontend to nero AAC.
Getting to your question, I was unaware that there were differences in the bitrate with my command and the Nero CD ripper. This is interresting to me, as I thought that I was getting maximum efficency out of Nero with my EAC method. I can think of 2 things that possibly cause this. One is that there is a lowpass cut-off of frequency being set on the Nero CD ripper, which would result in a smaller fidelity range and also smaller bitrate. If the music still sounds transparent at the smaller bitrate, then this is obviously what we're looking for. The second option is that Nero CD ripper is using a different VBR range for their encoding presets then the aacenc32.exe font end does.
There are other command line arguements that you can experiment with to try and match this target bitrate with aacenc32.exe. I would recommend setting some kind of low-pass filter, but you would have to ask some of the other experts on these settings. I am sure there are audiophiles on these boards that know exactly the right settings to use. I am sorry that I can't be of more help to you. If I find anything else out I will post back. In the meantime here are some of the command line options you can use in aacenc32.exe
Ahead AAC Encoder v3.2 (Frontend by LoggerSoft v0.79.064)
Usage: aacenc32.exe [options] <infile> [outfile]
OPTIONS:
CBR (constant bitrate):
-cbr <bitrate> set the bitrate in kbps (16 - 448)
VBR (variable bitrate, the default):
-vbr <VBR mode> set the VBR mode:
tape - lowest
radio - low
internet - medium
streaming - medium
normal (default) - high
extreme - high
audiophile - higest
transcoding - ultra
Quality:
-quality <quality> set the encoder quality. Use "high" (default) for
high quality or "fast" for fast encoding
AAC encode profile:
-profile <profile> set the encoder profile ("LC" or "HE").
TAG options:
-artist <value>
-album <value>
-title <value>
-track <value>
-genre <value>
-year <value>
-comment <value>
Miscellense:
-pns switch on PNS mode
-k keep all frequencies
-lowpass <freq> frequency (Hz), lowpass filter cutoff above "freq"
-highpass <freq> frequency (Hz), highpass filter
-aac output to ISO 13818-7 AAC (default output - .mp4/.m4a
container)
-nofir disable FIR-prefiltering
-notag disable any tag fields written
-fir <taps> taps count for FIR filter (5-2048), default 128
-zs kill zero samples at the begin & end of the
input file
-mono [param] convert input file to mono, "param" may be
"left" "right" "mix" (default) or number of channel
These are all of your options when encoding. If you knew all of the options that Nero CD ripper has on then we could probably make a good deduction on what is different. I think that the key lies in a lowpass and highpass filter being set. I don't know what values to use though. Anybody out there know the answer to kornchild's delimma?