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bweeks_hcjb
12-02-2004, 09:35 AM
I have encountered a problem with clipped audio being ripped. The CD that prompted me to investigate is "Offerings II" by Third Day. It is an enhanced CD with a Quicktime video, but otherwise all seems normal. I ripped it with Accurate Rip enabled, and it came back with a Confidence level of 2 or 3 on all tracks. So others have ripped the same audio. Unfortunately, there is some obvious clipping in the louder parts of songs.

I did not have any DSP effects on nor normalization, and the rip was to stereo, so it's not a problem of summing left and right. I tried 2 methods with equal results: Ripping to MP3, constant bit rate, 128 kbps, 44.1KHz. Also to Wav, 44.1 KHz, 16-bit.

I've ripped other CDs without seeing clipping. Perhaps they do not have full-scale audio.

As a final test, I recorded the audio in Cooledit 2K via the soundcard, the CD being played on the computer's CD drive. The results of that recording show no clipping. So that makes me think the CD is fine. Also, the dynamic range between audio peaks and quieter sections is greater than between the clipped peaks and the same quieter sections of the digitally ripped version.

I am using dMC version 10.1 with Professional Frequency Conversion "ON" (though there is no frequency conversion happening on these rips).

So I am wondering if there is some accidental gain occurring in Audio CD Input. Any thoughts, ideas, solutions? Thanks in advance for any help on this.

Brent

adaywayne
12-02-2004, 12:05 PM
Try ripping using CDex (http://www.cdex.n3.net/) which has a ripping volume selector. If it works in real time, that should solve any clipping problem.

xoas
12-02-2004, 12:06 PM
There is a modest volume normalization applied by dBpwoerAMP Music Converter (dMC) which exists apart from the DSP effects. I don't know as it can be turned off. What you should be able to do is to apply the Volume Quieten DSP when you rip these tracks (assuming you have Power Pack).

Best wishes,
Bill Mikkelsen

Spoon
12-02-2004, 12:46 PM
If you rip to Wav (every option [as source] and AccurateRip has a 2-3 confidence then the original CD has the clipping (ie if you play it through a Stereo with optical out, it will clip also), so the problem is the mastering of the CD.

Not suprising many CDs these days are badly mastered, just so when they are played on the radio they sound louder, and more will buy them.

I have a Still Dre track that badly clips on the base, one of the worst I have seen.

adaywayne
12-02-2004, 01:55 PM
Excellent point, Spoon. I listen to only classical and jazz so do not encounter this pr (orhaven't so far, to my knowledge) problem.

bweeks_hcjb
12-03-2004, 01:01 PM
So while it was mentioned that there might be a hidden gain in dMC, I assume that there isn't. Can you please confirm that Spoon? I can't see why you would include such.

I ripped with volume quieten (25% reduction) and the result is still clipped, just -2.5dB down now.

There should be a law against selling CDs that have been mastered with clipping!!! It's one thing to apply lots of compression, but obviously clipped - ugly.

The analog playback no doubt results in some overshoot on clipped parts, making the peak level look higher relative to lower volume sections of the music that weren't clipped.

Thanks for Accurate Rip, Spoon.

Spoon
12-03-2004, 01:53 PM
No gain is applied, unless Volume Normalize is selected - if all DSP effects are cleared then the data from the Audio CD goes straight to a wav file, no messing.