Thank you very much I am going to study the posts you have highlighted and if I have any doubts I will ask you.
Thank you again for your support.
Maybe I should take a video. To be most clear so I don’t misunderstand, do you see your arm wobble at the resonant frequency and actually skip? I only see skipping almost when I go on the torture track otherwise I don’t see anything in the resonance frequency test. You have a short armwand just like mine, do you actually see it wobbling? I remember seeing wobbling when testing my pivot JWM VPI tonearm.l but that was the 12” I believe.
If I have high frequency resonance does it mean my arm is too light perhaps?
This means if I add weight to the headshell the resonance should move down, am I correct?
It may be wobble or it may skip. It may also cause server distortion. Yes. I saw the arm shocked violently when it was close to 5 Hz. It started even a little before 5 Hz.
With the hifi news test record bands 2 and 3 are the lateral and vertical cartridge/arm test sweeps. At resonance the cartridge body will be moving at its maximum, these are the peeks as shown in this graph.
View attachment 761432
At resonance you may actually see the cartridge body moving but not necessarily. The test tracks have a 1khz pilot tone recorded over the low frequency tones. At resonance the cartridge body is moving side to side or up and down deflecting the cantilever as it does so. This deflection causes the stylus to "scrub" in the groove resulting in a speed variation of the stylus relative to the groove. This speed variation is called wow as in wow and flutter. The turntable speed stability thread goes into quite a lot of detail on this topic. This wow modulates the 1khz pilot tone and is heard as a warble.
If your arm has good damping the severity of the resonant peek will be reduced and may be very difficult to see or hear on the test tracks, you may have to use an oscilloscope to be able to determine it. This is unlikely to be the case with the terminator as, correct me if I'm wrong, it has no external damping.
So if you can't see or hear the frequency band in which resonance occurs it may be because the resonance is outside of the frequencies covered by the test record or it may be because your arm is well damped.
For the best results you want to have a combination of the correct frequency and damping.
Niffy
View attachment 761432
At resonance you may actually see the cartridge body moving but not necessarily. The test tracks have a 1khz pilot tone recorded over the low frequency tones. At resonance the cartridge body is moving side to side or up and down deflecting the cantilever as it does so. This deflection causes the stylus to "scrub" in the groove resulting in a speed variation of the stylus relative to the groove. This speed variation is called wow as in wow and flutter. The turntable speed stability thread goes into quite a lot of detail on this topic. This wow modulates the 1khz pilot tone and is heard as a warble.
If your arm has good damping the severity of the resonant peek will be reduced and may be very difficult to see or hear on the test tracks, you may have to use an oscilloscope to be able to determine it. This is unlikely to be the case with the terminator as, correct me if I'm wrong, it has no external damping.
So if you can't see or hear the frequency band in which resonance occurs it may be because the resonance is outside of the frequencies covered by the test record or it may be because your arm is well damped.
For the best results you want to have a combination of the correct frequency and damping.
Niffy
This weekend I will try to install the cartridge on the heavier wand I have (now I am suing an extremely short carbon fiber wand which might only weight 4-8gr).
This should move the resonance into a lower frequency.
On the scope I Don't see any peak I just see the waveform disappearing which I don't know if it is the end of the test track but it doesn't seem to be or it is the resonant frequency (it happens at about 5-6Hz).
By definition the resonant frequency should be a peak and not a null.
You are correct Terminator arm is not dampened so I wonder why I don't see the excitation frequency wobbling a little the arm. This might be like you have mentioned the frequency is outside of the test range.
The question that arise is: is it above 20Hz or is it below 5Hz?
Like I said I will put the cart on the heavier wand and see what happens.
If that's the case then if I increase the mass then I would push it even lower.
You might be correct in saying the resonance is below 5Hz.
I wonder if I should even bother with reinstalling the cartridge on the different armwand or focusing on the development of the tonearm!
Hi Stefano,
The trans-fi website shows the carriage including cartridge weight of just over 80g. They (dishonestly?) claim this as the entire lateral mass. This mass doesn't include the moving L section part of the air bearing or the hangers which probably add a further 30-40g and both of which add to the lateral mass. Have you weighed all of the moving components of your terminator and if so how much does it weigh? What cartridge are you using and what is its compliance? If you have a cartridge with a compliance of 15um/mN the resonant frequency will likely be just below 4hz. This shouldn't be a problem, you just can't confirm this frequency with the hi-fi news test record.
Niffy
The trans-fi website shows the carriage including cartridge weight of just over 80g. They (dishonestly?) claim this as the entire lateral mass. This mass doesn't include the moving L section part of the air bearing or the hangers which probably add a further 30-40g and both of which add to the lateral mass. Have you weighed all of the moving components of your terminator and if so how much does it weigh? What cartridge are you using and what is its compliance? If you have a cartridge with a compliance of 15um/mN the resonant frequency will likely be just below 4hz. This shouldn't be a problem, you just can't confirm this frequency with the hi-fi news test record.
Niffy
I don't get what you mean by the L section. There is no hanger nor L section moving along with the carriage. The only mass moving laterally is the slider, the arm wand and counterweight.
I have measure the carriage I can't recall the exact weight I will do again.
My cartridge is the Goldfinger statement which is 15 um/mN
I have measure the carriage I can't recall the exact weight I will do again.
My cartridge is the Goldfinger statement which is 15 um/mN
Hi Stefano,
I think the bit I called the L section is the bit you call the slider, it forms the moving part of the air bearing. The bits I called the hangers are those that sit on the slider and loop underneath the bearing track onto which the carriage sits, they also form the lower part of the vertical pivot.
I haven't heard a goldfinger but have only seen glowing reports. Definitely a cartridge out of my budget range. It was designed specifically for the clearaudio linear arms, I wonder if there is anything in its design that gives it an advantage over other cartridges when used in a linear arm.
Niffy
I think the bit I called the L section is the bit you call the slider, it forms the moving part of the air bearing. The bits I called the hangers are those that sit on the slider and loop underneath the bearing track onto which the carriage sits, they also form the lower part of the vertical pivot.
I haven't heard a goldfinger but have only seen glowing reports. Definitely a cartridge out of my budget range. It was designed specifically for the clearaudio linear arms, I wonder if there is anything in its design that gives it an advantage over other cartridges when used in a linear arm.
Niffy
I see what you are seeing. the Hanger part is glued to the carrier so the total weight includes that, as you can't separated them out.
Goldfinger is really leaps and bounds above other top cartridges I have tried.
Not sure if it has any advantage on linear or not, I know people using it successfully on both linear and pivot systems.
Do you suggest me to install cartridge on a heavier arm or to just focus on this project?
Hi Stefano,
I don't think changing to the heavier wand will tell you much that's useful. It might be a good idea to add mass to the slider in increments to see how this effects the performance of your cartridge. This could prove useful in determining the ideal mass for your airbearing project.
If my estimate of the total moving mass of your arm is correct at about 110-120g then you are probably already approaching the upper limit of the goldilocks zone for your cartridge. If adding mass to the slider decreases sound quality then I wouldn't build your project any heavier than the terminator. If on the other hand adding mass improves sound then keep adding mass until it doesn't.
Niffy
I don't think changing to the heavier wand will tell you much that's useful. It might be a good idea to add mass to the slider in increments to see how this effects the performance of your cartridge. This could prove useful in determining the ideal mass for your airbearing project.
If my estimate of the total moving mass of your arm is correct at about 110-120g then you are probably already approaching the upper limit of the goldilocks zone for your cartridge. If adding mass to the slider decreases sound quality then I wouldn't build your project any heavier than the terminator. If on the other hand adding mass improves sound then keep adding mass until it doesn't.
Niffy
I will think about what you mentioned. Bottom line I would like to see the resonance frequency to be within the measurable ranges.
I will try to play with weight on the slider, although I wonder what is the difference of adding weight to the slider as opposed to the armwand. I feel adding it to the armwand will affect directly the vertical resonance than adding it to the slider.
I will try few solutions.
I will try to play with weight on the slider, although I wonder what is the difference of adding weight to the slider as opposed to the armwand. I feel adding it to the armwand will affect directly the vertical resonance than adding it to the slider.
I will try few solutions.
Personally, I don't worry about the Terminator's lateral resonance frequency. It will be around 4-5 Hz. However, its vertical resonance frequency may be problematic. Its arm has two additional pivots so its vertical resonance frequency is based upon its headshell, arm wand, and counterweight. The L-shape slide is not a part of its vertical effective mass. Its vertical resonance frequency can be very high. The vertical resonance frequency test in Hifi News Test LP has up-limit 15 Hz. If the arm doesn't reflect its resonance frequency while you are playing this track. Its resonance frequency will be higher than 15 Hz. If so, it is a design problem.
Another way to test resonance frequency is to use Track 3 Pink noise vertical, in The Ultimate Analogue Test LP. Please see the attachment. Play the track and record it in Adobe Audition. Then, open frequency analysis window. You will see the resonance frequency.
Jim
Another way to test resonance frequency is to use Track 3 Pink noise vertical, in The Ultimate Analogue Test LP. Please see the attachment. Play the track and record it in Adobe Audition. Then, open frequency analysis window. You will see the resonance frequency.
Jim
Attachments
If you add weight to the arm wand you will be affecting both the vertical and lateral performance of the arm. You won't know whether any changes in sound is due to changes in one, the other or both. By adding weight to the slider you only affect the lateral performance so you will know that any changes are only due to changing lateral mass (and possibly the pressure in the air gap).
When making changes it is always a good idea to only make one change at a time.
The ideal lateral frequency will be a balance between reducing lateral errors due to eccentricity (by making the arm lighter) and reducing the amount the cartridge body moves at audible frequencies (by making the arm heavier). As I previously mentioned I aimed for 4.5hz with my arm. 4.5hz for your cartridge should be around 83g. As your cartridge is very heavy at 16g this would only leave 67g for everything else. By dropping to 4hz your total mass budget increases to 105g (89g without cartridge). I don't think you would want to go lower than 3.5hz but this would increase your mass budget to 138g (122g without cartridge). The added design flexibility, increased rigidity and reduced cartridge movement the greater mass budget gives could easily outweigh any shortcomings.
Niffy
When making changes it is always a good idea to only make one change at a time.
The ideal lateral frequency will be a balance between reducing lateral errors due to eccentricity (by making the arm lighter) and reducing the amount the cartridge body moves at audible frequencies (by making the arm heavier). As I previously mentioned I aimed for 4.5hz with my arm. 4.5hz for your cartridge should be around 83g. As your cartridge is very heavy at 16g this would only leave 67g for everything else. By dropping to 4hz your total mass budget increases to 105g (89g without cartridge). I don't think you would want to go lower than 3.5hz but this would increase your mass budget to 138g (122g without cartridge). The added design flexibility, increased rigidity and reduced cartridge movement the greater mass budget gives could easily outweigh any shortcomings.
Niffy
Yes that was clear. I am going to weight the slider tonight and post. When playing vinyls I can notice a left and right motion due to eccentricity of the disc itself, I am assuming this to be normal.
I am concerned however the vertical mass in this case is too light and pushes the resonance too high.
The linear air bearing will have damping path like super has implemented and Kuzma has followe it shortly after, which should take care of eccentricity issues hopefully.
That is a very good idea. I will play pink noise and feed t in to my spectrum analyzer to see where the resonance lays on.
I can only assume that to be the vertical resonance frequency.
I don’t have at the moment the ultimate analog lp test but I had presented it and should have shipped and arrive to me along with another couple of test records from Clearaudio early next week.
In alternative I can also install the Clearaudio Titanium V2 which is lower compliance and lower weight I assume and see what changes. I never installed it since I have the goldfinger so it’s still sealed in box.
I am itching to see if I can see any resonance using that.
Just curiosity, has anybody bothered measuring the L and R ch output of their cartridge and if so is it possible that the my are like 0.5dB difference?
I measured that on the GFS as I can only hear one ch being slightly predominant and I have verified phono which is within 0.02dB whole line stage even less but found the cartridge to have a 0.5dB.
I wonder if my cart is flawed and if so if I have to send it back to Clearaudio or if azimuth is really off but it is installed fairly vertical or maybe it’s normal to have these tolerance.