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Pooner
06-06-2008, 06:35 PM
I originally (several years ago) encoded my whole CD library to WMA lossless 24 bit 44.1khz. At the time I picked 24 bit ignorantly thinking it was better than 16 and kept going with it.

So recently I purchased an Apple TV and wanted to batch convert my library to ALAC, however dbpoweramp would not let me. The files apparently have to be 16 bit 44.1. So I batch converted my whole library to WMA lossless 16bit 44.1 and then again to ALAC.

Here is my question.. finally. Did I potentially compromise any quality/purity of the original EAC ripped file in going from WAV ----> 24bit WMA lossless ---> 16bit WMA lossless ----> ALAC lossless?

Thank you.

LtData
06-06-2008, 08:06 PM
No, lossless is lossless. Do not that there is a DSP effect that would have reduced the bitrate when re-encoding your 24-bit WMA files that would enable you go directly from your 24-bit WMA to ALAC: "Bit Depth".

LeoDavidson
06-10-2008, 01:57 PM
I'd re-rip a song or two to 16-bit and check that it's identical to the files you had in 24-bit and converted to 16-bit. If it's the same then you can be confident nothing bad happened.

Remember to compare just the music parts of the two files, without any tags/metadata. If you decode them to WAV using something that doesn't write tags to the files then you can probably do a simple binary comparison on the files. Or use a tool for comparing wav files.

In theory the 16-bit audio would have been zero-padded to 24-bits, and then truncated back to 16-bit, so you wouldn't lose anything, and a couple of songs confirming that fact would give me confidence that the whole collection was fine.

(Sometimes when you convert between 16 and 24 or vice versa a tool will use dithering or other effects to give a higher quality result, so it's worth a quick check, IMO.)

LtData
06-10-2008, 07:01 PM
If you have dBpoweramp Reference and have installed the Reference Codec Pack, you have a "[Calculate Audio CRC]" that only calculates the CRC based on the audio data.

ohrsantos
07-28-2008, 02:06 PM
I wanted convert some of my FLAC 24/28 to ALAC, however dbpoweramp would not let me. The files apparently have to be 16 bit 44.1.

I've made a research and ALAC "IS" not just compatible with 24bits but with 48KHz and 96Khz. For short ALAC is full compatible with HD audio especification and multi channel.

Why Cant I convert form my Flac 24bits/48KHz directly to ALAC. I wanted to to that, first because is pratical and second to keep all the file tags copied as well.

Is that a problems with dbpoweramp converter?

Thanks

Spoon
07-28-2008, 03:28 PM
Our alac encoder is cd quality only.

dmdevotee
08-15-2008, 05:04 PM
Our alac encoder is cd quality only.

is there any way to convert a 24 bit wav to a 24 bit apple lossless?

iTunes doesn't keep the folder structure