ct, Michael Fremer is FOS. He uses a SAT arm "the best sounding arm ever made." By the way the largest benefit of a linear tracker is not reduced tracking error. It is no skating force in theory. The major defect is a horizontal resonance that is going to be too low or a vertical one that is too high messing up the bass (most common)
No linear tracker except the Walker has survived the test of time. With the exception of the Clearaudio they are all inherently more complicated and prone to failure and deteriorating performance. The Clearaudio is prone to dirt. On the other hand a good pivoted arm is immortal as long as you don't drop it or let your wife use it. Skating is controllable within limits and tracking error can not be heard. I personally have never heard a linear tracker sound better than a pivoted arm. I have never heard one sound as good as a Kuzma 4 Point 14 with a Koetsu in it. |
ct0517, raw BS I'm afraid. Just what is that horizontal bean going through the air bearing? A perfect vacuum? It may have less horizontal mass than other linear arms but there is still a marked discrepancy. It is IMHO the best design for an air bearing arm almost identical to the Walker. Wonder why they stopped making them? Anyway I am still of the opinion that the best way to do a linear tracker is by having the horizontal axis servo driven. The physics of the situation does not change just because you do not like it. It should be horizontal effective mass by the way. The horizontal and vertical masses are the same. The effective masses are much different.
Terry9, yes, look at a picture of the Walker. Look back behind the cartridge to the intersection of the arm to the horizontal beam, the part that goes through the air bearing. At the intersection there is a clamp that joins the two. If you loosen the nuts you can twist the arm adjusting the azimuth and move it forwards and back adjusting the overhang or lack of overhang as it were. It is $120,000 but the money was not the issue, it is the design. This could be done with a stand alone arm probably for not much more than an Air Line. ET was doing it but stopped. I am not a big Walker fan. You get virtually the same isolation and performance out of an SME 30/12 with the V12 arm as you would with the Walker for less than 1/2 the price with no noisy compressors and air rushing around all over. |
Actually,the best air bearing arm is the Walker. It had the lightest horizontal mass. The air bearing is stationary and large. It uses a lower pressure (less noise). The arm is made out of some type of very light composite. The turntable section is actually the original Air Force, air bearing platter, air bearing suspension etc.
https://walkeraudio.com/proscenium-black-diamond-v/Unfortunately, Walker also sells a bunch of BS on their web site and I refuse to support that. I find it odd that the press has not compared the Black Diamond to the Air Force 1. |
Terry, you are using the best cartridge for a linear tracker, very low compliance. I be very interested in what your vertical and lateral resonance points are if you have a test record that breaks them up. The HI FI News record does this. Of course your stylus wears symmetrically. The net effect of a perfectly set up linear tracker (level) is no skating. The tonearm just oscillates slightly at very low frequency. The Koetsu is so stiff you might not be able to see it. In a way you are right. Warps occur in the vertical plane so a low horizontal figure is not as significant. The best design of all might just be the Clearaudio as the arm is short and It looks like the resonance frequencies might be closer together. I almost bought one but in viewing the videos I noticed in several cases the cantilever oscillation. The other problem is that the glass tube has to remain perfectly clean but it is open to air. |
I also forgot to mention that the general feeling in the press is that the 4 Point is better sounding than the Air Line. |
Terry9, I won't even look at an air bearing arm because of the problem of too much horizontal mass. The horizontal axis has to be driven and the arm has to have a passive horizontal bearing. Then you deal with tonearm effective mass like any other tone arm. Yamaha had the right idea but I think for the best motor isolation and reliability a belt drive would be best. It is however a tricky proposition. I believe a rack and pinion design would do it, the pinion being driven by the belt. Motion is so slow noise should not be a problem. The motor then has t have some type of servo control that predicts where the tonearm has to go. I envision a laser reading the groove just in front of the stylus. A groove is like the grand canyon next to CD pits. Should be easy to do. Unfortunately, small companies lack the technical horsepower to design this. It would be up to one of the big guys like Sony, Yamaha or JVC and they are not interested in such a small market.
I encourage every straight line tracker owner to closely observe their cantilever tracking the record. If you see the cantilever drift side to side even just a little you have a problem. |
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Dork, if your Terminator is so hot why are you selling it? Rube Goldberg could not have come up with that arm. But my absolute favorite was the Harmon Kardboard design with the rubber wheel that tracked a revolving drum! I won one in a raffle! Used it for 6 months or so. It worked! Sort of, as long as you did not listen to it. The revolving drum and rubber wheel rumbled and I could not figure out a way to dampen it out. Subwoofers were not all the rage back then but I was using two RH Labs subs and I guess HK didn't figure that into their design. It was so bad I bought another Linn. Sucker born every minute. |
Bill, I have owned two of them and played with God knows how many. It is nice that your Yamaha uses light beams as a limit switch. As I said above, when somebody does it right without compromise I am all in. It is great that you have kept your table alive so long and I love your dust cover. Yamaha was certainly headed in the right direction. But, a Sota Sapphire with a Kuzma 4 point 9 on it is going to sound better. Why? First it is suspended. The Kuzma is a very stiff arm with excellent bearings and it has no automation gizmos hanging off of it. It is also rigidly attached to the same platform as the platter fixing that relationship. When you increase the complexity of a rather simple but sensitive device you take risks and you have to spend a lot of money controlling all these variables.
It is just much harder to make a complicated device like a linear tracker work as well as a simple passive device. It is also bound to be less reliable and less durable. |
It has absolutely nothing to do with IMHO. Everything that I said is a fact of life. The best linear tracker available today is the Walker and it still has an unacceptably high horizontal effective mass. I will say this again. The horizontal axis has to be servo driven and the arm has to have a horizontal pivot just like a normal pivoted tonearm. Some older linear arms worked by tripping a switch which activated the drive but the arm had to deviate from tangent to trip the switch negating the benefit and the systems tended to be unreliable. When some one develops a reasonably priced system that reads the groove right in front or behind the stylus driving the horizontal axis I am all in. Otherwise you are much better off with a good pivoted arm. How many reviewers use a linear tracker as their reference? Air bearings can create very low friction systems but do nothing to reduce horizontal effective mass. Mass is mass, friction or not and these systems are extremely sensitive to level. Keeping a turntable exactly level under all circumstances is very difficult. Just differences in record weight can change the level of a turntable unless it is extremely rigidly mounted. Then you have all that air rushing around (making noise) and the complexity of using a compressor. With a servo driven horizontal axis level does not mater as much and there is no wind noise. Put your ear next to the bearing and listen.
Again, don't believe me watch for yourself. The cantilever should appear dead straight at all times. With any linear tracker you chose you will be able to see the cantilever drift back and forth. I can understand the draw but when it comes down to reality these arms are just not ready for prime time. |
jag, linear tracking arms are a waste of time and money. The technology to do it correctly has not yet been developed. The problem is that the horizontal effective mass of these arms is too high creating a very low horizontal resonance point. All you have to do is watch the cantilever closely and you will see it oscillate slowly back and forth. This creates more tracking error than a good pivoted tonearm not to mention oscillating skating force. In order to do this right the tonearm has to be driven in the horizontal plane by a servo mechanism. Little switches are too inaccurate and fragile for this. You would have to have a laser reading the groove right in front of the stylus. It can be done but at this point would be very expensive. If you are concerned with tracking error get a 12" tonearm. |
