Trubble Encoding to Mp4/AAC

[Codec Newbie]

Hey Spoon and the gang,

I'm looking to use dBpower to rip songs for my iPod. I've downloaded both the MP4 / AAC decoder, and the FAAC encoder, but I cannot get CDs to rip straight into AAC/MP4 format. It's all there to select in the Rip To menu (FAAC), but when I try to rip an error window opens saying 'the CODEC required to compress *SONG* could not be opened. Unable to run encoder'. What should I do? I'm new to audio files and codecs, so any help would be appreciated.

Looks like a great product by the way, well done Spoon.

Brendan

[xoas]

Re: Trubble Encoding to Mp4/AAC

What are the settings (format, bit setting, bitrate, frequency, channels) of your source file and what settings are you using for FAAC encoding?

[Codec Newbie]

Re: Trubble Encoding to Mp4/AAC

How do I check all that stuff? Today's the first I've used this program, so I'm not sure. i want the rip to be at 44000, 256kbps in stereo. All I can find is that FAAC compression settings are at 100 from the pull down menu, and the source files are CD Audio tracks.

[xoas]

Re: Trubble Encoding to Mp4/AAC

First problems first.
To rip your cd tracks to mp4 using FAAC, I assume you are opening the cd in dMC Audio CD Input, selecting FAAC as your encoding codec, selecting 100 as your quality setting and ripping. I assume that Audio CD Input is showing all your tracks and the track information for each one and that these are accurate.
If there is anything wrong about these assumptions, please tell us.

If this is all correct and your conversions are failing, open up dMC Configuration (Start>All Programs>dBpowerAMP Music Converter>Configuration>dMC Configuration), enable Professional Frequancy Conversion. While you are in dMC Configuration, check to make sure that dMC Configuration shows that your FAAC encoder codec is installed. If it is not shown please let us know. If it does show up, try ripping again.

If it still won't work, try ripping a test conversion (open your cd in dMC Audio CD Input, instead of FAAC select "Test Conversion"). If the test conversion fails please tell us about what Windows version you are using. If the test conversion does work, try ripping your cd to wav. If that works, try ripping the wav files to FAAC. Let us know if that works or not.

The dMC FAAC encoder will automatically set frequency, channels and bitrate based on the source file (your cd in this case) and your quality setting. The highest setting for this codec is 500. In several different tests, this comes closest to a 256 kbs bitrate. Test examples came in between 192 kbs and 225 kbs.

Hope this helps.
Best wishes,
Bill Mikkelsen

[Unregistered]

Re: Trubble Encoding to Mp4/AAC

Bill,

Thanks for your help. All your assumptions were correct. I've been able to get FAAC to encode no worries, at 100 quality setting. What does Professional Frequency Conversion do? I'm going to try again with 500 setting, and with song numbers/track listing all correctly set. Have yet to see if these files will transfer to my ipod though.

Cheers

[xoas]

Re: Trubble Encoding to Mp4/AAC

Professional Frequency Conversion is a routine that greatly improves conversions that involve a change of frequency (such as 48 khz wav to 44.1 khz mp3). As indicated in the Help Section (Start>All Programs>dBpowerAMP Music Converter>Help>dBpowerAMP Music Converter Help), this routine results in slower conversions but improves success rate and quality of these conversions as well as some others.
Best wishes,
Bill Mikkelsen

[hans-j�rgen]

Re: Trubble Encoding to Mp4/AAC

I would like to add that you usually don't need to resample a normal audio CD input when using FAAC in order to produce .m4a files for your iPod, because it will simply use the 44.1 kHz of the CD input. But if you want to use lower bitrate/quality settings than ~90kbps/~75%, it's recommended to downsample the 44.1 kHz input to 32, 24 or even 22 kHz sample rate, because this will increase the coding efficiency of FAAC. See also the table on the Wiki page at Audiocoding.com:

http://www.audiocoding.com/modules/wiki/?page=FAAC

Using FAAC at much higher quality settings than the default 100% is not necessary most of the time, because the AAC/MP4 standard should sound transparent for normal sounding input files at ~128 kbps. If you mostly listen to unusual sounds like baroque solo instruments or heavy metal music, it might be necessary to increase the VBR quality. The best way to find out your personal limit is to test a few files with your preferred music at different settings until you cannot tell the difference to the original input file anymore.

[Codec Newbie]

Re: Trubble Encoding to Mp4/AAC

Thanks Hans for the info, I'll give it a go. Being new to the whole notion of differing audio formats and variable bit rates and all that, I just needed to know some of the basic principles - your link proved a great help.

specs