Vinyl restoration cookbook

Cookbook: Vinyl restoration

More and more people have a CD-R or even a CD-RW at home today. And when an empty CD costs as much as a cassette tape, an excellent option has arisen. And due to the greater quality of the CD format, you simply don't by vinyl record anymore. You probably can't get hold of them either, and that includes some of your favorite albums not been re-mastered to CD either.

Solution 1: Do a vinyl to CD conversion yourself. A new problem arises: just because you have sampled the LP into a CD format, it won't sound better; it still sound "LP".

Solution 2: Find a way to remove the noise, scratches and pops! Here Pristine Sounds comes handy. The vinyl restoration tool has the ability to reduce rumble & grooves, noise and pops & clicks, and at most times it may be done without side effects.

This cookbook tries to explain the features of the Vinyl restoration tool, and the other features of Pristine Sounds that can help you restoring the original sound of your favorite record.

Setting up a strategy

The vinyl restoration tool of Pristine Sounds have several functions. It can remove noise, rumble and impulse noises. The tool is presented as an all-in-one tool that can do a restoration in one go. The most efficient way of doing a restoration however is not to use the VRT alone, but to complement it with the other features of Pristine Sounds.

Here is a presentation of how to utilize Pristine Sounds to a maximum.

Among the less great properties of a vinyl record are that it induces pops and clicks with time. It may be because of dust in the grooves or more often, very small cracks that have originated from various ways. The main feature of the VRT is to reduce, or preferable remove those impulse noises. You may also remove noise and rumble in the same go, but those modules are only included for you, that don't have enough time. Cleaning up a bad recording takes time.

The most efficient way of restoring vinyl in Pristine Sounds is:

1) Reducing impulse noises with the VRT pop & click module.

2) Reducing noise and rumble with the native image noise reduction tool.

3) If the natural ambience have been damaged, you may use the room simulator or the reverb to add an extra touch.

Reducing impulse noises with the VRT pop & click module.
The default values for the pop & click module are usually quite good.

Removing impulses from a recording is a two-step-process:

First you need to find the impulses, then you need to remove them. The sensitivity slider sets a threshold to what can be considered unwanted impulses. Do not worry that the volume of the recording is too loud or weak. The sensitivity property takes that into consideration. When are there reason to change the sensitivity? If too much "music" is considered impulses (some voices and synth sounds) it will be distorted and start to rumble. Then lower the sensitivity. "But sometimes some very obvious clicks get unaffected! I must raise the sensitivity!" If you notice that the music starts to "rumble / distort" then you can actually try to keep the sensitivity low but instead run the VRT more than one time. Pops that are too close to each other may not all be removed. That is a deficiency of the finding-algorithm. If you run the session one more time, those extra pops may be found.

The second step is removing the impulses. The strength slider says how much the local area around the pop will be affected. Mostly you really don't need to change this. If you raise the strength too much, the sound may get distorted.

If quality is needed, (and when is it not?) you should always use the S-Comp objects. The pop & click S-Comp object tries to analyze the effect of the pop-removal, and the global S-Comp object analyze the effect of all operations. Please use them both at all times! The effect is always audible, but they take some extra time. If you use the global S-Comp object, you can also use the "mono restoration" feature. If the recording was originally in mono, this will always produce a better result! This is based upon the fact that a mono recording is placed in the middle of the panorama and the noise & impulse noises floats all around it. The "mono restoration" feature of the global S-Comp object combines the common factor of the two stereo channels and place them into one mono signal (distributed onto the two stereo channels). Recordings that are in mono, can be seen as being two recordings! Left and right version. Where one channel has a click, the other may be perfectly ok, and vice versa.

Reducing noise and rumble with the native image noise reduction tool.
There is a built in noise reduction module in the VRT, and often it works satisfactory, but to get the best result you must use the native image noise reduction tool in Pristine Sounds. For that you need to have a silent part with only noise & rumble in it, but you can always find some of that in the beginning of the record.

The room simulator and the reverb
The room simulator plugin have been built into the VRT as well, and the result will be identical if you you the built-in or the native, but you should always apply reverb or room ambience after the noise reduction. If time is at premium, you may want to use the reverb2000 instead of the room simulator. It is more neutral and gives a greater Hi-Fi feeling. The '(mix) fatten.r2000' reverb is often suitable, with a 20m room and maximum stereo spread.

Sampling the record.

Plugging the turntable into the soundcard.
The absolute first step in the LP 2 CD conversion is to sample the vinyl record. Here arises a small problem. As opposed to sampling other sources, you cannot plug the turntable directly into the computers soundcard. It simply wont work. First, the pickup is a passive component. The electrical current produced has a completely mechanical origin, and the voltage is far to small to be used in the line-input of the computer. "Well I'll use the mic. inputs instead?" No, most microphone inputs in computer soundcards are of a really bad quality! Secondly, the vinyl records are actually recorded with an extremely unnatural filter curve. To minimize the pickup swing, and to afford more tracks per inch, the bass in heavily muted. The treble on the other hand is heavily amplified because the waveform component of a high frequency sound mostly is very weak. All those filters must then be reversed with an RIAA filter curve. That is not present in your soundcard; but it is in your stereo! So you have to bring out your stereo as well as your turntable if they are separate. Connect the turntable to the phono inputs. Most stereos have a "record output" or similar, with an output level matching a line level. Put that into your line input in your soundcard.

Putting the record on the turntable
Is your record free from dust? Well you cannot wash away the scratches with water, but very well the dust.

Putting the pickup on the record
Try to listen some on the record. It is important that the pickup is balanced. If the pickup rests too heavily on the record, the rumble will be much stronger. If the pickup lies to gently, then there will appear to be more pops and clicks, and there will actually be some false impulse-noises. If you don't have a pickup which you can balance with a counterweight, try to place a small coin on top of the pickup, but please be careful!

Pressing the Record button
With Pristine Sounds you can monitor the volume of the waveform before recording. You probably want to record as loud as possible. Try to sample some times to see if the waveform can be amplified without the loudest point being distorted. Remember that if you can amplify the digital waveform 6 dB within Pristine Sounds you actually lost 1 bit during recording. It pays of recording as loud as possible to begin with.

Then, make sure that you have enough hard-disk space. 5 minutes will cost you approximately 50Mb.

For more information: info@pristinesounds.com