15.   De-clicking and De-crackling  (part 2 of 2)

Time to remove the crackles and pops.

You can remove crackling with a number of different presets, using sound forge's crackle remover.  Once you are familiar with this tool, you can experiment around, and find out what pleases you.  As a lover of the natural sound of records, I tend to use this tool for exceptionally damaged records only.  (heavy scratching, worn, or heavy dusting).  I have spent hours trying to find the right medium.  Go to far over the top with this function, and many of the high end frequencies will be corrupted, and to little will leave to much of the crackling.  Try this to get started.

First go to DX Favourites, then select Sonic Foundry.  You will then get a considerably large sub menu, with all the different processes listed in alpha order.  (Figure G) 

Select "Click and Crackle Remover", and you should have something like this.  (Figure H)

Before clicking "ok", make sure that all the settings match the ones above.

Sensitivity (1-- 20)  = 20
Click shape (1-- 8)  = 8
Maximum click size (0.1-- 3 ms)  = 1.5  (don't go over 2.3)
Noise level  =  Select "Medium"
Un-tick the "remove low frequency rumble" box.  You have already done this.
Un-tick the "Keep residual output" box.  This will just make things sound very messy.

(Figure I)  Now let's save this preset, so we can use it next time, without making all the manual changes.  Go to "save as", then in the "save preset" dialog box, call it something.  I have named it "High precision crack remover).  Click "ok".    In the "click and crackle removal" dialog box, click "ok" again, and your computer will take a few moments to remove the crackling.  The time your computer takes to do this, very much depends on the speed of  your processor. 

Play the wave and have a listen to see how much of the crackling it has removed.  You may want to do a undo and go to the "Click and Crackle removal" again and try some settings of your own.  Pull the sliders up and down and see what it produces.   You may want to lower the "Sensitivity", or you may want to push the "Maximum click size" higher.