Vinyl effect?
Vinyl effect?
Can anybody shed some light on what the vinyl effect exactly does? is it really ment as a way to emulate the characteristics of vinyl or is it more like a gimmick?
Olaf
Olaf
The Story behind Live`s "Vinyl Distortion" Device
The "Vinyl Distortion" emulates the so called "geometric distortions" which occur during playback of a recorded groove with a needle.
Geometric distortions occur even if we assume that the groove represents a perfect picture of the original material. This assumption is not that wrong since the cutting head of a good cutting unit like a Neuman VMS 70 or VMS 80 does a pretty good job on normal sonic material. Most distortions do not occur during recording but during playback.
A pretty easy way to figure out how much the playback process comes into the game is playing back your favourite record using a typical DJ pickup on a Technics and a highend cartrige mounted on a SME tone arm. You will be surprised !
Geometric Distortions occur since the playback stylus cannot be infinite smal. The perfect playback systwm would trace the bottom of the recorded groove.
In reality this does not make sense: The bottom is the part of the groove which first becomes dirty, the bottom is a bit softened out by the pressing porcess of the record and finally and most important a playback needle needs to be pushed into the groove in order to trace it. If it would have an inifinite smal tip, the pushing force would also be inifinite and destroy the groove. By the way this is exactly what happens once the needle is broken!
For this reason the needles`s tip has a sperical shape and does not trace the bottom of the groove but its walls. And this causes the Geometric Distortions.
In a simplified model these distortions can be devided into two seperate Parts : the " Pinch effect" and the "Tracing Error"
Tracing Error : Imagine a sinewave. ( draw it on a piece of paper )
Now imagine a circle roling over it, just draw a ball of the same size on diffent parts of the curve. If you draw an imagininary line from the center of the ball you will get a deformed sinewave where the deformation is a function of the frequency of the curve and the size of the ball.
This is the basic tracing error. In real life it is way more complicated because the two sides of the walls do interact and the stylus is not a ball. But the basic nature of the distortion is the same.
Pinch Effect : Imagine two sinewaves in parallel. ( take two pens in one hand and draw a sinewave ) The distance between the two lines is smalest at the zero crossing and is biggest at the turing points of the curves.
A pur mono recording of a sinewave whould look like this on a record.
It is the result of a pur lateral movement of a triangular cutting stylus.
But the playback needle also moves vertical with twice the frequency of the original sinewave. The result are added harmonics which are 180 degrees out of phase.
( This is why some people tend to say that the stereo image of a vinyl record is so much better then on CD. It is not better, it is artificially enhanced during playback and it also creates new overtones, thus giving a more brilliant playback, easilly exceeding 20 kHz with a good playback cartridge. btw.: Every recording on vinyl needs a digital delay line in the recording pass because of input signal dependent automatic groove width adjustment which is essential if you want to cut more then 5 minutes on a record. )
These two effects are what Live "Vinyl Distortion" can provide.
On a real record there are two more things going on :
- If the frequency / amplitude ratio gets to high, the groove temporary gets smaler then the radius of the playback stylus. It cannot trace the groove anymore and heavy distortions do occur or the signal does not appear at all because the needle slips over it.
- the elastic nature of the vinyl counteracts the distoritons. If vinyl would be diamant it would sound way more agressive. fast movements and strong sudden accellerations are softened out.
The paramters of Viny Distortion :
- Tracing "Drive" / Pinch "Drive"
Amount of distortions caused by the above mentioned effects. In real life a function of : - amplitude, needle shape, playbsack speed ( less on 45! ) and position within the record ( gets higher at the center ! )
- the two bandpass filters :
In my original design ( i wrote my diploma about it ) i did incorporate two complex filter functions to shape the distortions in a way which comes close to the result of my messurements on real records. But i found the sonic results with the two stupid bandpasses much more exiting ! And thats why they are there. Typically both filters should affect the high parts of the frequency range, but it also sounds cool if the Pinch EQ is tuned low.
The two filters are in the analysis part of the simulation, they do not color the resulting distortion directly !
- Soft/Hard button :
The real model of the pure Geometric Distortions is the "Hard" one. But since the elastic behaviour does counteract them i made a second one which is closer to sonic reality, "Soft"
- Mono / Stereo
Pinch effect occurs 180 degrees out of phase, "Stereo". You can force it to be "Mono". Has nothing to do with vinyl, but if you like it ....
- Crackle :
A joke. A random function, some filters, a bit experimental tuning of the parameters. Volia. Was invented because there was some space left over in the graphic design.
If you really really want to go hardcore:
"DISK RECORDING" Volume 1 Groove Geometry and the Recording Process, Anthology of the AES Society. All Papers of the Journal of the AES Volume 1 - 28 ( 1953 -1980 ). This is the bible part one. You need a big bag to carry it. Heavy content heavy volume...
"DISK RECORDING" Volume 2 Disk Playback and Testing, Anthology of the AES Society. All Papers of the Journal of the AES Volume 1 - 28 ( 1953 -1980 ). This is the bible part two. You need a big bag to carry it. Heavy content heavy volume...
Cheers, Robert Henke / Ableton
Geometric distortions occur even if we assume that the groove represents a perfect picture of the original material. This assumption is not that wrong since the cutting head of a good cutting unit like a Neuman VMS 70 or VMS 80 does a pretty good job on normal sonic material. Most distortions do not occur during recording but during playback.
A pretty easy way to figure out how much the playback process comes into the game is playing back your favourite record using a typical DJ pickup on a Technics and a highend cartrige mounted on a SME tone arm. You will be surprised !
Geometric Distortions occur since the playback stylus cannot be infinite smal. The perfect playback systwm would trace the bottom of the recorded groove.
In reality this does not make sense: The bottom is the part of the groove which first becomes dirty, the bottom is a bit softened out by the pressing porcess of the record and finally and most important a playback needle needs to be pushed into the groove in order to trace it. If it would have an inifinite smal tip, the pushing force would also be inifinite and destroy the groove. By the way this is exactly what happens once the needle is broken!
For this reason the needles`s tip has a sperical shape and does not trace the bottom of the groove but its walls. And this causes the Geometric Distortions.
In a simplified model these distortions can be devided into two seperate Parts : the " Pinch effect" and the "Tracing Error"
Tracing Error : Imagine a sinewave. ( draw it on a piece of paper )
Now imagine a circle roling over it, just draw a ball of the same size on diffent parts of the curve. If you draw an imagininary line from the center of the ball you will get a deformed sinewave where the deformation is a function of the frequency of the curve and the size of the ball.
This is the basic tracing error. In real life it is way more complicated because the two sides of the walls do interact and the stylus is not a ball. But the basic nature of the distortion is the same.
Pinch Effect : Imagine two sinewaves in parallel. ( take two pens in one hand and draw a sinewave ) The distance between the two lines is smalest at the zero crossing and is biggest at the turing points of the curves.
A pur mono recording of a sinewave whould look like this on a record.
It is the result of a pur lateral movement of a triangular cutting stylus.
But the playback needle also moves vertical with twice the frequency of the original sinewave. The result are added harmonics which are 180 degrees out of phase.
( This is why some people tend to say that the stereo image of a vinyl record is so much better then on CD. It is not better, it is artificially enhanced during playback and it also creates new overtones, thus giving a more brilliant playback, easilly exceeding 20 kHz with a good playback cartridge. btw.: Every recording on vinyl needs a digital delay line in the recording pass because of input signal dependent automatic groove width adjustment which is essential if you want to cut more then 5 minutes on a record. )
These two effects are what Live "Vinyl Distortion" can provide.
On a real record there are two more things going on :
- If the frequency / amplitude ratio gets to high, the groove temporary gets smaler then the radius of the playback stylus. It cannot trace the groove anymore and heavy distortions do occur or the signal does not appear at all because the needle slips over it.
- the elastic nature of the vinyl counteracts the distoritons. If vinyl would be diamant it would sound way more agressive. fast movements and strong sudden accellerations are softened out.
The paramters of Viny Distortion :
- Tracing "Drive" / Pinch "Drive"
Amount of distortions caused by the above mentioned effects. In real life a function of : - amplitude, needle shape, playbsack speed ( less on 45! ) and position within the record ( gets higher at the center ! )
- the two bandpass filters :
In my original design ( i wrote my diploma about it ) i did incorporate two complex filter functions to shape the distortions in a way which comes close to the result of my messurements on real records. But i found the sonic results with the two stupid bandpasses much more exiting ! And thats why they are there. Typically both filters should affect the high parts of the frequency range, but it also sounds cool if the Pinch EQ is tuned low.
The two filters are in the analysis part of the simulation, they do not color the resulting distortion directly !
- Soft/Hard button :
The real model of the pure Geometric Distortions is the "Hard" one. But since the elastic behaviour does counteract them i made a second one which is closer to sonic reality, "Soft"
- Mono / Stereo
Pinch effect occurs 180 degrees out of phase, "Stereo". You can force it to be "Mono". Has nothing to do with vinyl, but if you like it ....
- Crackle :
A joke. A random function, some filters, a bit experimental tuning of the parameters. Volia. Was invented because there was some space left over in the graphic design.
If you really really want to go hardcore:
"DISK RECORDING" Volume 1 Groove Geometry and the Recording Process, Anthology of the AES Society. All Papers of the Journal of the AES Volume 1 - 28 ( 1953 -1980 ). This is the bible part one. You need a big bag to carry it. Heavy content heavy volume...
"DISK RECORDING" Volume 2 Disk Playback and Testing, Anthology of the AES Society. All Papers of the Journal of the AES Volume 1 - 28 ( 1953 -1980 ). This is the bible part two. You need a big bag to carry it. Heavy content heavy volume...
Cheers, Robert Henke / Ableton
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