Please Help - Source/Output Audio Properties Utility

[mike_j_johnson]

Is there a utility out there that will tell you the properties of an audio source file, and then tell you the properties of the output (after the audio has been processed by your media player and sound card)?

I am trying to achieve bit perfect audio.

My source is 16bit 44.1kHz .cda (CD Audio).
I am using Foobar with Kernel Streaming mode (to bypass the Windows kmixer).
Also, I am using the X-Fi Audio Creation mode with bit perfect playback.

Now I want to verify that I am indead hearing exact 16bit 44.1kHz audio.

The problem is that usually the Windows kmixer and/or the soundcard will upsample 44.1kHz to 48kHz.

Any ideas?

 

[agent420]

I can't think of any software that does that, but perhaps you could record the digital output of the card and compare it to the original file.

Do you have some reason to believe the stream is corrupted? Do you think you hear distortion of some nature?

Please don't take this as a personal attack, but I sometimes think people get carried away with the semantics of audio processing. I mean, for one thing, there is error correction starting right inside the cd player. I'm not certain that sequential playback of the same track from the disc will consistantly return an identical bit stream, especially for common consumer playback drives. Then there is always the matter of the quality of the rest of your system. Unless you are fortunate enough to have a high end amp and speakers, I don't think you could discern between a bit here and a bit there. It could well be that your playback system isn't even capable of reproducing the difference between the two.

From the description of your setup, I don't think your system should be upsampling. Granted, upsampling has been an issue in the past, but if you can't tell the difference what would it really matter?

I guess I'm just saying that bit perfect audio might be a laudible goal, but the reality is our brains can't easily distinguish many low level imperfections, and if you listen to any lossy codec like mp3's, that goal is thrown right out the window. In fact, simply the analog conversion to digital is a compromise, but very few (if any) people can truly abx 44 vs 48.

 

[mike_j_johnson]

I agree with ya for the most part

I just think it is kinda frustrating that something as simple as 1:1 audio and video is so difficult! Why do so many things in the system have to touch and mess with the source signals???? The more I read about this stuff, the more I found out how much of a pain it was to achieve bit perfect audio. Hopefully Vista's re-write of the audio code will help.

I have the following (not claiming this is anywhere near audiophile quality equipment):

X-Fi Elite Pro (the one with the highest quality DACs)
Belkin PureAV cables connecting the soundcard to the powered sub
Klipsch ProMedia Ultra 5.1
Monster Cable speaker cables for all speakers
Monster Cable AC cable for the Sub

Now I think bit perfect will only work with 2 channel lossless CD audio. Reason I say this is because Dolby Digital, DTS, EAX, etc. need a DSP to decode/process the sound format. The way I understand it, bit perfect will output in 2 channel (stereo). Please correct me if I am wrong.

 

[agent420]

I believe you are correct. And I understand your frustration... you're right, it shouldn't be that complicated. But I think you've got all the bases covered by avoiding the Windows mixer and using those settings on your card; those are the two primary places that the bitstream can be unknowingly modified. Until recently, Creative was always a little shady when it came to how the audio was really processed internally. For that reason and many others, I avoid Creative like the plague. I occasioanlly play games, but my primary setup is used for recording and mixing, with a Presonic Firepod audio interface.