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JackA JackA is offline
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Default Digital Audio Restoration

On Tuesday, October 20, 2015 at 3:48:55 AM UTC-4, Peter Larsen wrote:
On 19-10-2015 18:13, JackA wrote:
On Monday, October 19, 2015 at 12:41:31 PM UTC-4, Peter Larsen wrote:
On 19-10-2015 03:13, JackA wrote:
Unofficially released.
Harry Belafonte - Mama Look A Boo Boo, (title varies) 1957.
Audio restoration...
http://www.angelfire.com/empire/abpsp/images/bubu-s.mp3

Jack


Left Right
Min Sample Value: -32768 -32768
Max Sample Value: 32767 32767
Peak Amplitude: 0 dB 0 dB
Possibly Clipped: 12 4
DC Offset: 0 0
Minimum RMS Power: -81.67 dB -83.41 dB
Maximum RMS Power: -4.76 dB -4.3 dB
Average RMS Power: -9.83 dB -10.02 dB
Total RMS Power: -9.33 dB -9.54 dB
Actual Bit Depth: 16 Bits 16 Bits

Using RMS Window of 300 ms

- Peter Larsen


Is that a F- grade???


Yes, F-.


You people are cruel!! :-)

Consider what I had to work with. It's from a bootleg CD, first time stereo, never published by RCA (Victor)/BMG etc. (this is Take #6, tape condition unknown). It started out decent, but the the fidelity and volume went south, until the ending. So, I had to trim (or as you call it, clipped) to TRY to keep constant volume and enhance key frequencies. I feel it turned out pretty good.

Take this fine song from the MCA boxset. Lynyrd Skynyrd - Saturday Night Special. Just sounded washed out, lead vocals too low - that was common with many early (re)mastered CDs. I enhanced some frequencies (caused spikes), then watched the VU meters. Sure, I trimmed (clipped) some, but it didn't harm the recording!!...

http://www.angelfire.com/empire/abps...satspecial.mp3

Thanks.

Jack


Expected Crest factor for content considering that it is vox intensive
is 25 dB, not 10 dB.

Also why is it clipped? - mp3 decoding can cause overruns but as long
time participant here you know that. And where is the record noise?

Like the DC offset score; always check that! :-)


That is also bad. There is a lot of vox. Vox is naturally asymmetric. It
should probably be slightly positive.

- Peter Larsen

Thanks, Peter!!!

Jack