Continuous Noise Filter on shellac

[Beautman]

One thing I'm having a pretty hard time with is the continuous noise filter on accoustic laterals (and to a somewhat lesser extent on electrically recorded shellac). I start with the pre-set for 1903 acoustic or 1940 shellac, and while it does a great job on the noise, I find it is too aggressive on the remaining program material, leaving it too rolled off and dead-sounding for my taste. I'd rather let a little more noise pass and get more vibrant and lifelike tonality.

What I haven't figured out is a straightfoward way to accomplish this, at least without playing around with settings for hours and only sometimes getting good results. By simply using the threshhold shift, I got much nicer tone on the program material with reasonably low groove noise, except that I also end up with a bed of low level swirley metallic sort of sounds that are completely unnatural and distracting. I'm have this problem on fairly clean and unworn 78s.
Any suggestions about what I should be doing here?

[Craig Maier]

Re: Continuous Noise Filter on shellac

First of all, do not use the preset fingerprint if you need to get optimum results. Those pre-programmed presets are there for convenience, not performance. You need to take a fingerprint of each recordings noise distribution, since they will all vary. Next, I would start with the attenuation control set to around 20 and the attack to 10 to 20 mSec. Lastly, I would use the mouse to adjust the blue inflection points in the range of 5 to 20 KHz until you get the desired tradeoff between noise removal and frequency response. Experiment with differing FFT sizes as well. Avoid using the overall raise or lower threshold control if you really want to optimize the systems performance. I hope that this helps.

[Beautman]

Re: Continuous Noise Filter on shellac

That's certainly helpful, thanks.

Maybe you could clarify something: Is the objective to avoid creating digital artifacts, or to permit them and then filter them out?

Also, what about doing a first pass using the dynamic noise filter on a light setting and, to the extent appropriate, high and low pass filters, so that there is less for the continuous noise filter to have to deal with?

[This message has been edited by Beautman (edited 02-19-2001).]

[Craig Maier]

Re: Continuous Noise Filter on shellac

After de-clicking, I de-crackle all 78's with the Median filter set to 3 or 4 samples depending on the record. Next, my method is to use the Continuous Noise Filter in a manner so as to minimize artifacts to begin with. I also use it relatively lightly and THEN apply the Dynamic noise filter (also delicately).