Removing Surface Cruft in Software?

[waxcylinder]

Sometimes people dont want perfection, they just want music to sound like they remember it.

Like my son for instance ...

When I digitized my old 45s many of which had had a very hard like on our old jukebox, I worked hard to clean them up removing all the pops/clicks etc. When I gave him a copy of the set he complained saying that he preferred them the way they used to sound on the juke box - with all the "noise"

================================

Personally when I digitized my LPs I preferred to replace them with CDs where available (at a sensible price). Though in some instances the recordings had been "remastered" - and the re-masters were not an improvement on the original, in which case it was back to a vinyl transfer.

My particular pet hate is recordings that were originally mono being re-issued in a faux stereo - but that's easily fixable by squishing the two "stereo" tacks back to mono.

Good luck with the continuing project and have fun with it (I'm now working on my wife's LP/tape collection),

WC

[Tom Dennehy]

The longer sound sample is 307 KB. Too big?

[steve]

he complained saying that he preferred them the way they used to sound on the juke box - with all the "noise"
....
the re-masters were not an improvement on the original

Like father like son

The longer sound sample

I don't think that we need a longer sound sample.
The noise is very severe and it is "broadband noise" (a wide range of frequencies). We are unsure of the cause of the noise, but as it is in a few specific places on one album only, the problem is clearly with the vinyl and not with your equipment. It may be due to a bad pressing, or perhaps someone has attempted to play the record with a broken stylus that has badly scraped the groove (and tried in several places before giving up). Whatever the cause there is not much that can be done to repair it.

The first thing that I would do is to use the Amplify effect to bring the level up a bit.

Broadband noise cannot be "filtered" out because filtering will also remove the sound that we want to keep.
We also noticed that there is some low frequency modulation of the audio so we had better remove this first.
Use the high-pass filter with a frequency setting of around 40 Hz and a slope of 6 dB per octave. This should be applied to the entire track.


Spectral processing techniques, as used by the "Noise Removal" effect probably give the best chance of improvement.
Don't expect miracles - the damage is very severe. At best we may be able to make a little improvement.
See here about the Noise Removal effect http://manual.audacityteam.org/man/Noise_Removal (after reading that, the next part should make sense).

A problem we have with using the Noise Removal effect is that we need a "noise only" sample to create the noise profile, but we don't have one. So the first thing we need to do is to find or make some noise that has a similar character to the noise that we want to remove.

To create a noise sample, I created a new stereo track (Tracks > Add New > Stereo Track), then selected about 4 seconds of this empty track (click and drag along the track). Then I used the Nyquist Prompt effect (Effect menu) to generate some customised noise.
Copy and paste this code into the text area of the Nyquist Prompt effect:

Code: Select all

(sim
  (mult 0.05 (noise))
  (lp
    (clip 
      (mult 
        (eq-lowshelf (noise)1000 -12)
        (s-max 0 (hp (lp (noise) 80) 80))
        10000)
    0.1)
  5000))

This will generate some noise that is similar in character to the noise on the track.
With this noise selected, open the Noise Removal effect and click the "Get Noise Profile" button. You won't see anything "happen", it will just make a "profile" of the noise and then exit.
Now select the damaged area of the track and bring up the Noise Removal effect again.
Try these settings:

Noise Reduction: 24
Sensitivity: 0
Freq Smoothing: 200
Attack/Decay: 0

Then click the OK button.
BEFORE you loose the selected area, apply the Amplify effect with "Amplification dB" set to about 4 dB. (this will compensate for some of the gain loss that occurred with the Noise Removal effect.

It should end up sounding something like this:

Honeysuckle Rose cleaned.wav

Before / After repair

(1.17 MiB) Downloaded 78 times