Reed 5T Opinions

bobbydd,

Thank you for this information.  The 5-T is basically a conventional arm located on a rotating base that allows for near perfect tangency and eliminates the offset angle which means no skating force.  It is good to know that the basic design of the arm is good.  

Don't know specifically about the Reed 5T, but I can say from experience that I'm getting great results with a Reed 3P, in conjunction with an Ortofon Windfeld Ti cartridge.  Tracking is fantastic, very clean sound.  Plus, it's beautiful to the eye and in use.  I realize there are design differences among the arms.

The 3P costs around $6K, nowhere near the 5T price wise.

@lewm , I forgot to mention. Your analysis of the significance of Zenith is right on. We should all go back to spherical styluses and give Wally one less angle for barter. Next will be barometric pressure.

@thekong , Very few of us get to utilize equipment in our systems at length if at all before we purchase it and awareness of technicalities is helpful in making decisions as to what you buy or not.

Kuzma makes some excellent equipment. He also makes some not so excellent equipment. Few of us can score a hit every time.

The basic design of the Safir is excellent like the 4 Points. Its effective mass limits it to a small number of very low compliance cartridges. Mr Kuzma's assertion that you can run cartridges with a resonance at 3 Hz would be true in a perfect world but, it is not. Records are not perfectly flat and turntables are not perfectly quiet. There is plenty of very low frequency noise that would energize a resonance that low. I have done this experiment. For yuks you should try it. You won't break anything. Just be ready to use the lift.

@ dover, there are many people who are very capable of analyzing the design of a turntable without having built a single one. By your own argument you are obviously not one of them. Instead of attacking me personally why don't you just explain why I am wrong. Usually, when you see attacks like this it is because the individual is incapable of having a discussion about the technicalities of an issue. Your analogy of the car door totally fails. The door is not suspended by a spring. Although it has detents to hold it open at certain points it will not spring shut when you open it and let it go (unless you are parked on a hill). By having the counter weight on a spring you just add another resonance frequency. The counter weight moves at the same speed and distance as the stylus it's mass is part of the system and can not be divorced. 

Turntables (unless you are Nakamichi or B+O) are extremely simple devices. There are many people who have built their own turntable. Precision bearings are readily available as are great motors and control systems. Only and audiophile can make such a simple device as complicated as a General Electric GE90.

@mijostyn 

He definitely has moments of genius but he will make whatever people think they want to buy so, he makes one of everything and is committed to not much. 

Franc Kuzma has been producing audio products for many years. His turntables and tonearms are lauded around the world - even by yourself on these forums.

How many turntables and arms have you manufactured and sold ?

@mijostyn 

Also, what on god's green earth makes you think the counter balance of the ET arm is decoupled? It has mass does it not? 

From your comments it would appear that you have never seen an ET2 or understand it.

The counterweight sits on the end of an I beam, which is connected to the air bearing spindle via a leaf spring. 

Try leaving your car door open and driving off - does the door stay open - no its hinged - and so as the car moves the door rotates about the hinge.

ET2 works exactly the same. 

Why don't you go to the Eminent Technology site and actually read up on the arm - you might learn more clearly how it actually works instead of guessing..

@mijostyn , I am no engineer, so I can't even start to argue with Frank Kuzma on his design and viewpoint. I posted the link not because I agree or disagree with it, but just thought it would be an interesting viewpoint for discussion on effective mass and resonance frequency.

I have been using a Rockport 6000 for nearly 20 years, and when set up correctly with appropriate cartridges, I can't hear any problem. Can I get better sound (to my ear) with another tonearm? Who knows? But then I also have one of your beloved Schroder CB, and a 4Point 14". Both of these arms, as well as the Rockport, have their own sets of characters that I like. For audio equipment, I usually based my judgement on actual usage and listening, rather than on theories!

What I found interesting, as Dover has stated before, is you seem to keep changing your stance from post to post! In a recent thread you started, you stated the new Kuzma Safir looked like a winner, and you thought the 4 Point 9" was a better design than the SAT. Now that I posted a link on Kuzma defending the high mass of their Safir arm, all of a sudden, according to you, Kuzma just " has moments of genius but he will make whatever people think they want to buy so, he makes one of everything and is committed to not much. "

Not sure if you aware, the Kuzma Safir, which you thought looked like a winner, has a 60g effective mass. While it is still lower than the horizontal effective mass of the Rockport / Kuzma Airline, it is higher than that of Dover's ET. So, if you think the ET would bounced around at 2-3 Hz, the Safir would be even worst.

@lewm , yes you did. Sorry about that. 

@dover , yes, I am talking about any air bearing arm. The problem is that the vertical effective mass of these arms is much lower than the horizontal effective mass. The cantilever, the suspended part, has to move the tonearm in two directions, up/down and side to side. Up/down the cantilever only has to move (suspend) the wand, bearing housing, counter balance, headshell and cartridge. The masses farthest away from the fulcrum have the most significance. In the horizontal plane there is no fulcrum. The masses of everything mentioned above plus the mass of the air carriage count in full force as they all have to move the same distance as the stylus. It does not matter if there is no friction. If you tune the system so that the vertical resonance point is within reason the horizontal resonance point is going to be very low, 2-3 Hz. What happens is the cantilever starts moving towards the spindle and it takes a bit for the tonearm to respond. Once it starts moving the cantilever has to stop the arm, the arm overshoots and the cycle repeats. Under every circumstance I have looked at you can actually see this happening. The cantilever shifts back and forth. Even if you can not see it the stylus is oscillating from one groove to the other. You can attenuate this by adding a horizontal damping trough which some arms do but then the right channel groove wall has more work to do moving the arm through the damping fluid, the opposite of skating. There is no good way to make this work. Straight line trackers that move a more or less standard arm along in a mechanized carriage is theoretically a better way to do this if the mechanism can be kept quiet and reliable , The B+O table is an example. The Reed arms and the Schroder LT side step both problems by moving the bearing housing of the arms along a specific trajectory. The 5T does this in a motorized fashion again bringing up the noise and reliability issues. The 5A and the Schroder LT animate the bearing housing by capturing the force generated by friction in the groove. The same force that generates skating in offset arms. I have not had the chance to listen to any of these arms yet but I have enough confidence in Frank Schroder that I would buy an LT on the bet that it works as designed. Unfortunately at this point I do not have a table it will fit on...yet. I am of the belief that the major benefit of an arm like this is not it's reduction in tracking error but the absence of significant skating. I am all for low friction bearings but even with no friction you still have to deal with mass and inertia in a system with a spring loaded suspension no different than your car. Also, what on god's green earth makes you think the counter balance of the ET arm is decoupled? It has mass does it not? It moves at the same speed and distance the rest of the arm moves, right? Sorry dover but, it counts just as much as everything else and when you get a really good pivoted arm you will realize this. You you are determined to have as little tracking error as you can there are some excellent choices out there now.

@thekong , do your self a favor and add some lead weight to your arm until you get the combined resonance down to three Hz and let us all know what happens. Better yet make a You Tube for us! Give us a little forewarning so we can get the popcorn ready. Frank Kuzma is a very interesting fellow. You might notice that he makes one of everything. He makes mass loaded tables and suspended tables. He even makes suspended turntables that are not really suspended. He makes unipivot arms, gimbal arms, 4 point arms and air bearing arms. He definitely has moments of genius but he will make whatever people think they want to buy so, he makes one of everything and is committed to not much. 

@thekong 

An interesting white paper.

The ET2 horizontal effective mass can be as low as 25g less the decoupled counterweight compared to the 80g Kuzma Airline.

Kuzma ignores tracking and focus's only on resonance. I always thought the target of 8-10hz was partially based on keeping it above footfall on sprung floors which is typically around 4hz.

If you examine the Shure white papers on tracking, they have found that the fundamental resonance, if not dealt with properly, causes a scrubbing motion from the cantilever/stylus assembly. This causes tracking issues and of course distortion in the bottom and its harmonics that will distort up into the audible regions. I assume this is why they came up with the stabiliser brush.

Kuzma makes no comment on the impact of high mass on tracking at low frequencies, and there is no measurement indicated in the white paper.

Even Bruce Thigpen of ET states that on eccentric records, arms with high horizontal mass will be less accurate than lower mass arms.

Bruce Thigpen has measured wow and flutter on pivoted arms versus air bearing linear tracking and can demonstrate the linear tracker has lower wow and flutter.

His argument, supported by measurement is that there is typically more wow and flutter from a pivoted arm than from the TT itself.

For discussion on high effective mass, it would be interesting to take a look at the following paper by Kuzma on their new Safir tonearm with a 60g effective mass. In contrast to the common believe that cartridge / tonearm resonance frequency should ideally be in the 8-12hz range, Kuzma stated it would do no harm for the resonance frequency to get down to 3hz. 

https://www.kuzma.si/media/uploads/files/SAFIR%209%20Technical%20aspects%20220409(1).pdf

@larryi 

The dramatic difference in the inertial mass of air-bearing arms in the horizontal and vertical planes may be a problem or it may be a benefit. 

It's a benefit according to Bruce Thigpen.

By having differential effective mass in the horizontal and vertical plains you have 2 much lower amplitude resonant frequencies instead of 1 large one. If you have both resonant frequencies at the same point the amplitude is compounded along with the deleterious effects on tracking.

Bruce also makes the point that the ET2 does not pivot at low frequencies, whereas servo arms and low surface area air bearing arms will pivot at low frequencies - they are not rigid at low frequencies.

Larry, Reports from my friend who has taken up a formal study of zenith error tend to agree with yours, to the effect that cartridge manufacturing errors are paramount in determining the error.

Also, I agree with your point about inertial mass of linear trackers (air bearing or otherwise). Some reputable engineers evidently think that high inertia in the horizontal plane is desirable for best bass frequency reproduction. Not only do we see some pivoted arms like the Moerch with outrigger weights at the horizontal pivot but also we have the Dynavector tonearms which very deliberately also strive for high horizontal effective mass. I have mentioned this at least once before, but one rationale for that goal arises if you consider that bass frequencies, increasingly as f goes down, are generated by increasingly horizontal motion of the stylus tip. Since these frequencies generate a lot of energy at the stylus/cantilever, the high inertial mass would be seen to stabilize the pivot relative to the stylus tip, so that the tail does not wag the dog (from side to side). Fremer often repeats his bias view that horizontal and vertical effective mass ought to be nearly equal, and, right or wrong, his opinions have had an effect on others’ perceptions. I suppose he learned his opinion at the feet of one or another tonearm designer who feels the two should be about equal. But I have never heard or read a good argument for it.

lewn,

True, even with perfect zenith alignment, only at the null point would the contact area of the cartridge along the line of tangency.  But, the maximum error at other points will still be relatively small, whereas, zenith error in manufacturer is much higher, typically, according to the Wallytools people, plus or minus five degrees.  Still, I am not inclined to open that can of worms with my setup.

mijostyn,

The dramatic difference in the inertial mass of air-bearing arms in the horizontal and vertical planes may be a problem or it may be a benefit.  There are some arms, like the Morch Anisotropic arm, that deliberately increases the horizontal mass by using outrigger weights on the vertical axis (to reduce impact on vertical mass) so that the arm resists swinging side to side when large horizontal groove movements (i.e., monophonic bass waves) are presented.  This preserves such bass information (a lot of deep bass is recorded monophonically (side to side movement) in order to reduce big changes in depth of the groove that stereophonic  recording would entail),  I've heard that arm and it DOES have impressive bass response.  Likewise, I've heard impressive bass response from air-bearing arms, like the ET-2, and the high horizontal effective mass might be the reason.  But, I do worry about whether such arms put a lot of strain on the cantilever when it has to drag the whole setup across the record--not only is the mass high, the lack of mechanical advantage of a pivot means a lot of force is needed to drag that arm linearly.  This high sideways resistance to movement also makes we wonder if that means the cantilever is never tangent to the groove.  Still, I've heard nice sound from all types of arms, so I don't know if any are inherently superior.

This bit about zenith is fun, and it probably does show us another way in which vinyl is flawed. Now I will go back to ignoring it and enjoying the music. For a perfectly constructed cartridge in a perfect conventional overhung pivoted tonearm, zenith can be perfect for only two brief moments, at each of the two null points. Zenith is a correllary of tangency. For those who really want to fret about zenith, the only solution is a perfectly set up linear tracking tonearm. I don’t own one of those. The definition of zenith that I am using is: correct zenith occurs when a line drawn from one contact point through the other contact point on the stylus tip,if extended will pass through the center of the spindle. And, by the way, even a perfectly set up linear tracker won't get you to perfect zenith, if the stylus was not mounted square with the cantilever, and if the cantilever is not perfectly straight. (Well, to some degree you can correct for a bent cantilever by twisting the cartridge body.)

Mijo, if you re-read my post I did qualify my remark about skating force with the phrase “in a conventional pivoted tonearm”, which the 5T, 5A, LT, Thales, etc, are not.

I think you could do zenith with a regular USB by first aligning the cantilever horizontally or vertically in the field of view, and then changing the focus to look for the contact edge.  It would be even easier if the USB is capable of taking multiple images at different focal points and then integrating the images to get something that has a good depth of field, but, those scopes are about $1500 or more.  If you know the alignment of the cantilever, even if you cannot see it, you can see the stylus orientation and that would give you some idea about the zenith error.  I am sure an even fancier scope, would make this easier.

I sort of prefer not really knowing all of these things.  While I have a Fozgometer, I don't really use it that much.  I prefer to align the stylus visually to be perpendicular to the record surface.  If this is not electrically ideal with regard to crosstalk, I still rather do my records the kindness of having the stylus fit the groove properly.  VTA/SRA I set by leveling the cartridge and then listening to changes in the angle to find the right spot.  Basic alignment I do with a Smartractor.  This is more or less good enough for me.  I think record playing is robust enough to survive even rough alignment.

@mijostyn 

Your arm bounces across the record at 2-3 Hz. 

I assume you are talking about the Eminent Technology ET2.

How do you come to this conclusion.

@larryi, Of course they would say that. I have a relatively cheap USB microscope and I can see the long axis on modern extreme styluses such as the Gyger S. I do not have a measurement grid so I have to ball park it and since you can not see the cantilever you have to make sure it is perfectly aligned in the field which with a decent stage is not that hard. If the styluses i currently own have an error I am confident it is less than 1 degree. If I bought a cartridge that had a significant zenith error I would not be sending it to Wally Tools. It would be going back to the manufacturer as defective.

@lewm , quite correct in an offset arm but in these arms the wand is straight so little to no skating force is generated. More bearings are always a liability as you suggest which is why I prefer the Schroder LT. It has normal vertical and horizontal bearings and a magnets control the position of the single secondary horizontal bearing.  I would have gotten the Schroder LT but it requires a turntable that takes a 12" arm. The only table I am interested in that will do that is the Dohmann Helix but I refuse to waste money having to buy the vacuum up-grade when it is released if ever. If not then I am not interested. I am toying with the idea of modifying the Sota's plinth for the LT but in order to get an idea of what it would take I would have to have an LT in hand meaning I would have to buy one. That is a pretty big leap for something you might not be able to do.

@dover that is not the way it works dover. The motor is running continuously and the laser is pinpoint. It simply adjusts the motor's speed. If you look at the arm wand it's vertical and horizontal effective mass is virtually identical. In the case of your arm it is wildly different. What this amounts to is a very low horizontal resonance point. Your arm bounces across the record at 2-3 Hz. You can stop this with damping but then you generate reverse skating. In short, It is a terrible design.

When the arm is slightly out of tangent, a laser beam and sensor detects this condition and a servo motor slowly rotates base that the arm is on to reestablish proper geometry.  

So in a nutshell it is just like digital - only a little bit out all of the time ( apart from the start ).

Reminds me of the Goldmund linear tracker waltzing across the record -

2 steps forward, 1 step back, hippity hoppity boo, I see a new cartridge for you.

At least with the Goldmund you had a flashing led to show you how often the arm was out ( most ).

I'll stick to my air bearing linear tracking Eminent Technology ET2 if I want zero tracking angle error.

The 5a is based on a design like the Thales arm and so it has additional pivots to locate the arm.  That is not the case with the 5T.  With the 5T the arm’s motion is only restricted by conventional pivots.  When the arm is slightly out of tangent, a laser beam and sensor detects this condition and a servo motor slowly rotates base that the arm is on to reestablish proper geometry.  Other designs have used optical sensors and servos (like the B&O Beogram 4000), but, the slow rotation of the arm base is supposedly smoother and less likely to cause vibration.

"Normally this friction just generates heat." ...and the skating force in a conventional pivoted tonearm.

The term "zenith" seems to have been re-invented for our particular obsession.  If you look it up, there is no dictionary definition that fits Mijostyn's definition, but I think he got it right as it now applies to vinyl reproduction.  A friend who is well known in the industry has been looking closely at zenith for typical cartridges and typical alignments.  As I understand his messages to me, he finds that almost never is it perfectly right.  We are all living with bad zenith.  BAD, I tell you!

Sounds like the Reed 5A is somewhat like the Swiss Thales.  It just stands to reason that the complex bearing structure, no matter how beautifully wrought, must generate friction.  It remains to be seen how or whether that affects SQ.  Based on Molly's testimony probably not much if at all.

I saw the 5T at a show.  The base looks like it is too large for my Basis Debut.  What a relief, I won’t be tempted.  It is a thing of beauty, and the engineering appears to account for and mitigate all of the shortcomings of linear tracking design (except cost).  It works on the same principle as the Shroeder LT arm, except the rotating base is powered by a motor controlled by a laser sensor whereas the LT base moves from the drag of the stylus playing the groove and is controlled by magnets.  I wonder how these two arms compare in performance.

The Wallytools person I spoke to at a show said thar the $1250 microscope is used primarily to set VTA/SRA but that it is not useful for reading zenith. For that, you send your cartridge to them and they use an ultra expensive microscope and give you the zenith correction which you can make with another tool of theirs.  The representative said that none of the big makers of styli currently do a good job of accurately mounting styli as far as zenith is concerned, but they have said that they will look into this now that they have been shown data on this issue.  

@molly , Incredible rig molly. That is my favorite turntable. I am waiting patiently until it is offered with a vacuum platter which Dohmann has said is coming along. I did not know the 5A had been released. For those who do not know what it is, it is a manual version of the 5T using the same geometric trick but with clever bearing management instead of lasers and motors. The Schroder LT is another manual arm that uses the same trick. All three arms are not offset (they are straight) remain tangent to the groove within a fraction of a degree and do not require anti skating. What the arms are doing is using the frictional pull of the record on the stylus to drive the mechanism of the arms. Normally this friction just generates heat. 

Good luck with your table. I'm jealous!  

For those who have not heard the term, Zenith Error it is a new factor that Wally Tools has jumped on. Zenith error is a rotational error of the stylus. If you were looking down on the tip of the stylus the long axis of the stylus is not perpendicular to the groove. To correct it you would have to rotate the cartridge. In order to measure it you need a good microscope which Wally Tools will also sell you. Of course if your cartridge is built correctly you do not need any of it. You can see well enough with a decent and inexpensive USB microscope. The two cartridges I currently have, a Soundsmith and a Clearaudio are good enough that I can not see any zenith error. 

I recently purchased the Reed 5A.  Mark Dohmann set it up on a new Helix 1 MK2 turntable with the Hana Red cartridge (with a custom designed shim, from JR Boisclair at Wallytools.  The shim corrects Zenith error and an additional product included with the shim corrects the rake angle error.)

The sound is stunning, rivaling my Sonorus ART10 tape deck playing master tapes.  

This is, by far, the best sounding analogue reproduction I have ever experienced.  The arm is a beautiful design, and a pleasure to use and behold.

Highly recommended