Trusting your ears and knowing what you like to listen to are two very different subjects. Distinguishing fine differences in sound is difficult for humans because our audio memory is so short. Not only this but because of our brains ability to accommodate a system that sounds awful does not sound so bad after a while which is why you always trust your initial impression. Fortunately distortion being so dissonant is always easy to hear like the elephant in your garage is easy to see. Knowing these things makes you a much better listener. Most of what Cleeds thinks he hears is his brain screwing around with him assuming he has one.
Any pivoted offset tonearm that does not have anti skating can be thrown in the trash unless you want to jury rig a system for it. Turntable setup is not art, it is a science requiring extreme fastidiousness. There are lots of things brains can't do well which is why we have test records.
Raulruegas the best you can do is to set the bias so the stylus tracks the test record correctly. It is the best approximation you can get. Looking at the cantilever only gets you in the ballpark. This method will not work with very stiff cartridges like Koetsus. The other neat trick is to find an album with a blank side like Cleopatra by the Lumineers. You can get in the ballpark by adjusting the bias so the arm does not drift or drifts outward slightly when you play the blank. Never trust the scales on the tonearm. They are great for reference. For example if you are a cartridge jockey you record all the settings for each cartridge so you can return to them easily without having to go through the whole process again. |
Records do not have a steady state velocity unless you are playing a sine wave at constant volume. The higher the velocity the louder the volume the lower the velocity the lower volume. Obviously The overall velocity increases with groove speed. All of this usually does not effect the sound of the system but rather how the cartridge is tracking and wear on the stylus and record especially when the stylus is miss tracking. Miss tracking will cause noticeable distortion which I suppose you could say effects sound quality. Miss tracking occurs at the highest groove velocities. |
Oh Lewm, The speed of the stylus through the groove depends on the groove velocity not the speed of the record. The higher the modulation and frequency the faster the velocity. The stylus is traveling a longer distance in a given period of time |
ct0517 try it with a test record. Don't break the wires! |
Lewm only in a straight line. If you rub your finger against smooth glass at a specific speed and pressure you will encounter a certain amount of friction. If you rub your finger across 100 grit sandpaper at the same force and speed you will encounter more friction aside from taking your skin off. The groove is not that rough relative to the size of your finger but Newton's third law applies. In order to move the stylus relative to the cartridge and tonearm you have to apply a force which is what the groove does. The equal and opposite reaction is friction and heat. Unfortunately, the situation is so plastic given the variation in frequencies in combination I do not think there is any math to describe this. You are right about the effect of straight line speed on friction but a groove is anything but a straight line. The coefficient is probably not constant given the changing frequencies but I do not know this for a fact and I will try to fine academic support for that theory. I also think I can arrange an experiment. I can set the anti skate via a test record then play a smooth side at the same distance from the spindle as the test track and see which direction the tonearm slides. I'll get back with the results. |
Lewn Theoretically you are correct in that varying tangency will change the force vector but in real life the error is so small it does not account for much.
You are mistaking velocity with record speed. As the modulation increases so does velocity. In a heavily modulated groove the record has to exert more force on the stylus to move it and the stylus is moving faster. In a straight groove the record is applying only straight ahead friction and the stylus is not moving (through space) at all. The energy (work) required to move the stylus is seen as friction and a little heat. You could make the argument that anti skate does not decrease towards the center of the record because actual velocity does not change. There are just as many squiggles they are just closer together. And indeed it does not change as much as you would expect given the vast difference in groove speed between the outside and inside of the record. I did make a miss statement earlier when I said velocity decreased towards the inside of the record. It does not. Groove speed decreases towards the inside of the record. What would be nice is a test record with a bias band an entire side. That would be fun! |
Actually Lewm groove velocity takes into account the length of the path the stylus travels through the groove. The more tortuous the higher the velocity. The force required to move the stylus back and forth is seen by the system as friction. So, the higher the groove velocity the higher the friction. Groove velocity is not the speed of the record past the stylus. Velocity depends on speed, frequency and modulation. Accordingly, skating force decreases as the arm travels inwards. Most modern anti skate mechanisms compensate for this at least to some degree. Tracking angle error has very little to do with it as long as the arm is set up correctly. It is all about friction and offset angle and offset angle is fixed. |
Larry, yes when the groove velocity (modulation) increases friction of the stylus in the groove increases increasing the skating force. Groove velocity also decreases as you move to the center of the record. Now, do you set your tracking force to track light passages allowing mistracking on the heavy ones chewing up the grooves? I think not. Tracking force is set heavy enough to make it through the tough passages. Same thing goes for antiskating. You are adjusting it to minimize tracking distortion. Cleeds, please excuse me. I should have clarified myself better. I meant tracking distortion. Even order harmonic distortion can be euphoric. Pass intentionally designs a little of it into his amps. Other distortion not so, at least over 1%. Usually the bias adjustment bands are at mid disc. I guess the thought is to get an average velocity.
There are many variables you just can not account for. But, the goal is to minimize miss tracking. Any pivoted arm cartridge combination with properly adjusted anti skate is going to easily out track one without. Get a test record and prove it to yourself. If the stylus leans a little bit to one side or another makes no sonic difference. This is another reason so many of us don’t switch to a tangential tracker. There is no sonic improvement to justify the added complexity.
Larry, Peter has no idea what the cartridges he is reduilding have been through. The owners usually have no idea.
The primary determinants of the skating force in a given arm cartridge combination are VTF and groove velocity. Modulation is a minor contributor. The geometry of the best anti skating devices is such that the counter force applied decreases automatically at the arm moves towards the center of the record compensating for the decreasing groove velocity. |
Larryi you are essentially correct except for one thing. It is the loudest passages you want to set the tonearm for as they are the hardest to track. The lighter passages are easy and a little more bias here does not matter near as much. It is the stylus following the groove that you are interested in nothing else. Fidelity will not change at all until the cantilever is way off center in the non linear zone. Very stiff cartridges, very low compliance like the Air Tight and Koetsu might sound just fine playing a string quartet without anti skate. Put on Aerosmith and they will pop right out of the groove.
All this is the argument for tangential tonearms. I have had three of them and can guarantee they are way more headache and unreliable than a good pivoted arm. Just ask Michael Fremer. |
There is a huge difference between evaluating a change in sound quality and knowing what you like to hear. We have a notoriously short audio memory and if we listen to a system that sounds "bad" long enough after a while it does not sound as bad. This is why you always trust your first impression. Fortunately distortion is easy to hear because it is so dissonant, sort of like looking for an elephant in a garage full of cars.
Rouliruegas, the best you can do is setting the bias with a test record. That is what I mean by correctly and yes it is not perfect. It can't be. there are too many changing variables you can not correct for. Viewing the cantilever angle just gets you in the ballpark and even that does not work well with very stiff cartridges like the Koetsu. Another neat trick to get you in the ball park is using a blank record. Cleopatra by the Lumineers is a three sided disk. The forth side is blank. You adjust the bias until the arm starts to drift backwards playing the blank side then fine tune with the test record.
Any arm without bias adjustment is trash unless you want to jury rig a bias mechanism for it. The primary problem is not sound quality or wear. It is tracking distortion. Any arm without bias is going to miss track the outside groove wall at lower velocities than a properly set up arm. Any good test record will demonstrate that. They are relatively cheap. Don't listen to me. Prove it to yourself. Oh, do not trust the gradations on the tonearms. They are good for reference. Cartridge jockeys can write down the settings so that when they change cartridges they can go back to the proper setting without having to go through the whole routine again.
Creed, I am an MD and can guarantee you I know a lot more about the brain than you do. You are not your brain. You as a psychological entity are a maze of bioelectrical reactions taking place in what is hopefully a brain. Soon it might be in a computer. I can damage your brain and disrupt those reactions and you won't be there any more but the brain still is. Alzheimers disease is a way of doing it slowly. Now, where you go afterwards is a matter of debate. Audio sales people are generally headed south.
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Oh, I forgot to add. You do not need a Fozgometer or an oscilloscope to do this right with modern cartridges. A good eye and the right tools can do this perfectly. Back in the day cartridges were all over the place. Cantilevers set in crooked, styli not perpendicular to the cartridge body not to mention internal inaccuracies. But today I have not seen a single
Ortofon, Clear Audio, Lyra, Koetsu or My Sonic Lab cartridge that wasn't dead on. Don't forget you have to use cartridges that match the effective mass of your tone arm. You can always add weight to a stiff cartridge but it is much harder to subtract weight from your tone arm when you use a highly compliant cartridge. |
Stringreen, the most important thing I have learned in this passionate hobby over the last 55 years is, Never Trust Your Ears. The problem with ears is that they are connected to a brain. Brains can accommodate to stimuli in amazing ways. Example. You walk into a room with a really bad odor. In about 5 minutes you notice it is not near as bad but then another person walks in wrinkles their nose and says "boy it stinks in here!"
Always follow the science when you have it. Cartridges in pivoted tonearms track much better and have much lower distortion with anti skating set correctly. Setting up a turntable correctly is not easy. Very few dealers have someone who knows what they are doing. I hate to say this because as a company McIntosh's customer service has no equal but I just had to re adjust one of their MT5 turntables. Not only was it out of alignment but the resonant frequency was too high. I had to add 2 grams of lead to get it down to 10 Hz. It was supposed to have been set up at the factory.
Every vinyl jockey should have the tools and learn how to do this to get the best out of their turntable. These are, A protractor ( I like the DB Systems best), a pocket mirror, a bright light, a little engineers square, little screwdrivers, cartridge weights, a level bubble and a good test record like the Hi-Fi News Analogue Test LP. |
There are exactly two reasons why tonearms skate. The offset angle of the tonearm and friction of the stylus in the groove. The tonearm is being pulled towards the spindle leaving the stylus and cantilever behind forcing the cantilever's suspension into a non linear zone like trying to run a woofer pinned against the end of its excursion. What this effects most is the cartridges tracking ability. You can prove this to yourself with any good test record like the Hi-Fi News Analogue Test LP. Play the Bias Setting band and lift your anti skate weight. The left channel will start buzzing madly. Add a lot more weight and the right channel will start buzzing madly. Get it right and both channels play the test tones beautifully. This is the only right way to set anti skate and it is at best an approximation as the skating force changes with groove speed and degree of modulation. Any setup that sounds better without anti skating was not set up correctly to begin with.
Tangential tonearms that are set up correctly do not skate because they are dead straight. There is no force vector off the main axis of the tonearm. Their main theoretical advantage is that they don't skate, improving tracking no matter the speed of the groove or modulation. There is no audible benefit in them being perfectly tangent to the groove at all times and they have one major failing which is the effective mass in the horizontal plane is way higher than the vertical plane leading to two separate resonance points and stress on the cantilever moving that huge horizontal mass. Watch any of these arms with a reasonably compliant cartridge like the Ortofon Windfeld Ti and what you will see is the cantilever drift towards the record center and the the tonearm catching up to it in a cyclical manner. The benefits simply do not out weight the compromises which is why most vinylholics won't use them. I can make any of the better Rega or Project arms sound better than any straight line tracker. We are in the golden age of the turntable now. There are some fantastic inexpensive complete turntables out there. As long as you have them set up on a rock solid surface and the tonearm is set up right you will not be able to do better without spending stupid serious money.
Final trick of the day. If you want to get your azimuth dead on just get a thin pocket mirror and place it on your platter. Lower the stylus on it. Light up the stylus with a spot light and you will see the stylus and its reflection make an "hourglass." Adjust your arm until the hourglass is perfectly symmetrical.
This more than doubles your accuracy. |
If removing anti skating makes a vinyl playback system sound better then the setup is off somewhere. You can prove this to yourself with any good test record Like the HiFi News one. The anti skate adjust or Bias track has symmetrical test tones on both channels in increasing modulation.
The game is to adjust the anti skate until neither channel distorts at the highest groove velocity. Take the anti skate off and the right channel will start buzzing like mad. Too much anti skate and the left channel will start buzzing like mad. It helps to have continuously variable adjustment. If you do not then you can fine tune by adjusting the tracking force. You can get yourself in the ballpark by just keeping an eye on the cantilever as you lower the stylus into the groove. It should remain straight ahead. If it deviates one way or another you are way off. With no anti skating applied the cantilever deviates to the edge of the record causing misalignment of coils to magnets and taking the suspension out of it's linear region. |
