HydrogenAudio

Lossy Audio Compression => AAC => Topic started by: iphoneman on 2022-07-27 21:47:16

Title: Wav to AAC - Low bit rate Encountered
Post by: iphoneman on 2022-07-27 21:47:16
I have a WAV file that was recorded that SPEK shows as follows:

"PCM signed 24-bit little-endian, 4608 kbps, 96000 Hz, 2 channels.

When I run it through Foobar, at what I believe is the highest setting for AAC conversion, with the following parameters:

AAC (Apple) 320 kbps VBR Q 127

it shows up with a low bit rate (not 320) as follows:

"AAC, 142 kbps, 48000 Hz 2 channels"

The file itself is from the 1970's, so it should be decent quality.

Can anyone suggest why AAC is only outputting a 142 kbps file?



Title: Re: Wav to AAC - Low bit rate Encountered
Post by: Porcus on 2022-07-27 21:51:48
The obvious first guess is that you have encountered the "V" in "VBR": meaning that this song requires only 142 to give the quality (as guesstimated by the AAC encoder) that an average song would spend 320 on.

(Sure the file isn't mono encoded as stereo?)
Title: Re: Wav to AAC - Low bit rate Encountered
Post by: iphoneman on 2022-07-27 21:59:10
Thanks.

My bad. It appears I already asked this question, and just didn't recall.

This time, however, my source was unimpeachable (a PCM recording I made myself of an HQ stream that started life as lossless)