Cartridge loading


Presently I am using a ZU/Denon DL103 mc cartridge with ZU Audio's highest tolerances.  I had this cartridge mounted on my VPI Prime and after going through all the various loading combinations, I settled on 200 ohms.  I was always satisfied with my choice of setting.  I no longer have the Prime and now use the Technics SL1200G turntable.  After having the same cartridge mounted and aligned by the dealer, I inserted it into my system and enjoyed the sound immensely, never touching the 200 ohm setting.

Yesterday I was listening to vinyl most of the day and for some reason I found the sound to be better than ever, mostly in the treble area.  The highs had shimmer when needed and I had played the same records many times before on the Prime and they never sounded as good as they did yesterday.  Just for the heck of it, I checked the cartridge loading and found it was now set at 1000 ohms.  As I said, when I put the Technics into the system, I never bothered changing the loading which was at 200 ohms as it was the same cartridge, just a different turntable.

I believe I know what happened, when I last used the tone controls on my McIntosh preamp, (you have to shuffle through a menu) I must have inadvertently put the cartridge loading at 1000 ohms.  It truly sounds fantastic, better than I ever thought possible.  The Bass is still very deep and taut, midrange is the same but the treble, oh my, so much better.  Now the million dollar question is why should it now sound better at 1000 ohms, when it sounded great before at 200 ohms?  Can the tonearm on the Technics have an effect on cartridge loading?  I always thought it was all dependent on the preamp, amp and speakers.  What am I missing here?  I am very curious to know.  The specs for my cartridge say greater than 50 ohms for loading.

Thanks
83d96326 9a8a 4eca b738 6dc28f39ebbcstereo5
Tonearm setup has a lot to do with it too.  VTA, VTF.  Once you re-dial those in you may end up back at 200 ohms.  Lots of variables involved.

The cartridge was dialed in from the dealer and checked when brought home. Nothing was changed.
You're not loading it as much as you were. Loading damps and reduces air and detail. You know the way you can turn a bicycle upsidedown and turn the pedals as fast as you can and it really flies? Now try it with the brakes applied at various levels. Notice how it's more controlled when peddling against the braking? That's damping. 
Most of my MC cartridges are better with loading much higher than 100 Ohm, normally 1000 Ohm, 10 000 Ohm or even 47 000 Ohm is better. But do not expect that you will stay forever with a chosen loading, it depends on the mood. 

This arm is not optimal for your low compliance Denon cartridge, simply learn about tonearm/cartridge resonance. Your cartridge must be used with super heavy tonearm as the compliance of Denon is extremely low! 

Make sure to use the heaviest possible headshell and add subweight on the back of your tonearm to increase the mass of the arm as much as possible.  
Dear @stereo5  : I agree with those two gentlemans, you need to test it at 200 ohms again and try to fine tunning the cartridge/tonearm set up at that loading.

In the other side your Technics tonearm is spot on with that cartridge due that its compliance is over 10cu, don't worry in this regards.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
Cartridge loading is for the benefit of the phono section, not the cartridge!

It prevents the inductance of the cartridge and the capacitance of the tone arm interconnect cable from creating a resonant circuit, by detuning it. The resonant circuit can produce noise (often RFI) that is considerably more powerful than the cartridge signal itself!


The problem is that the loading resistor also causes the cartridge to do more work- it has to drive that load. The energy to do that comes from the stylus in the groove driving the magnetic generator in the cartridge, so the cantilever will get stiffer and less able to trace high frequencies.

So less loading will open up the highs in some cases. The problem is if the circuit resonance appears, it acts as RFI injected into the input of the phono section. If the phono section is sensitive to RFI it won't sound right- hence the need for loading. OTOH if the phono circuit designer understood this problem, then no loading at all is needed since the phono section will have no problem with the RFI. A side benefit of a proper phono preamp design is you will also experience less ticks and pops, as these can be caused by stability problems in the phono preamp!


At any rate always go with the least loading (highest resistor value) you can such that the system has correct tonal balance. 
Now try 47K and work downward from that value until you’re happiest.
@lewm ........My cartridge loading choices for Mc are: 25, 50, 100, 200, 400 & 1000 ohms.

@chakster ........the cartridge is in a milled aluminum body which is very heavy and absolutely no need for the extra weight. The set up of cartridge is perfect, why would I set it up again to load at 200 ohms? If it is set up properly, it should not matter as loading has nothing to do with correct cartridge alignment. The dealer (Adirondack Audio) put a lot of time setting up the cartridge and also used an oscilloscope in the process. When I got home, I rechecked the proper weight which was still spot on.

I am very happy at 1K ohms, I was just kind of wondering why.
Dynamic compliance of your DENON DL-103 cartridge is 5cu @ 100Hz , convert it to 10Hz and it will be 8.5 cu - this is extremely low compliance if you don’t know. Look at the specs of your Denon to check it if you don’t believe me. To convert 100Hz to 10Hz you need to multiply on 1.7, so this is why the compliance is 8.5 cu @10Hz.

The do yourself a favor and measure tonearm/cartridge resonance with a Test Record to make sure about resonance frequency.

Any cartridge with such a low compliance require tonearm with over 30g effective mass, Technics tonearm effective mass is about 11-13g as far as i know.

If your aluminum body made by Zu does not require a sub weight then it’s not heavy enough to increase tonearm mass twice as much!

Actually using an SPU on Technics tonearm is a perversion just like using Denon 103 on this arm. It’s like making a truck out of sport car. But the SPU models at least have an Elliptical or Replicant-100 stylus tip while your Denon 103 is a CONICAL (worst profile ever in the history, dirt cheap and full of distortion while playing).

Technics tonearm is a killer with high or mid compliance MM/MI or MC, but with the low compliance cartridges you’re close to the extreme.

I love Zu Audio speakers, but i don’t understand why you bought their Zu Denon for your tonearm ? Better cartridges with the most advanced stylus profiles and cantilevers are even cheaper than Zu Denon which is $750 as far as i know ? Maybe with harsh horn speakers a rolled-off Denon sound will help, but in a normal system it doesn’t (imo).

You can experiment with different loading for sure to find what you like, but you can change your cartridge to something perfectly match for your arm, it must be a mid compliance cartridge (not extremely low compliance like your Denon 103 / 8.5cu at 10Hz or 5cu at 100Hz).


@chakster ...........I bought the cartridge from Audiofeil ( sold via Audiogon) and was assured it was a good match for the VPI Scout that I bought it for. It was still pretty much brand new when I had it mounted on the Technics. In 2020, I plan to get the Dynavector DV 2X L cartridge as I owned the older model before and loved the sound. Do you think Audiofiel gave me a bum  steer?
@stereo5 47K is the standard for phono cartridge loading. 
I am very happy at 1K ohms, I was just kind of wondering why.

I explained why in my prior post. With a higher impedance load on the cartridge, the cantilever is more able to trace high frequencies.

What @atmasphere writes is very much what is causing your change in sound character. Loading at the phono stage and not at the cartridge is what you should be looking for. Also what phono cable are you using and do you know its capacitance? A very low cap cable should be what you use along with a higher resistive setting at the phono stage (like 1000 ohms) then you allow the cantilever to move freely in the groove, rather than a low resistive setting might stiffen the cantilever and make the cart work more.
If I load my Delos at 100 ohms the sound is closed, restrictive and bland, I load at 475 ohms and the sound becomes very dynamic and very high resolution.
I am using the VPI phono cable.
The Zu Denon is very much a "salt to taste" kind of cartridge when it comes to loading.  When I used one it could indeed sound quite different when using 100/200/300/500/1000 ohms.  And Zu will tell you there is no wrong answer here, just use what sounds best to you.
There is an interesting article in IAR #5 by Peter Moncrief titled "Audio Fallacies Exposed  Low Impedance Loads for MC Cartridges" about loading and he proposes that loading down a cartridge helps it keep better contact with the grove. 

Moncrief attacks the general held belief that 'loading a MC cartridge damps a HF ringing and the "dull sound" from too great of a load is simply an overdamped response'  He then goes on to show swept frequency responses of MC cartridges under varying loads showing minimal change in the frequency response.   

He then goes on to point out that loading down a cartridge has a sincere effect on the side bands created from 400hz + 4Khz intermod test track.  He shows plots of different load situations and it can clearly be seen that the more the MC cartridge is loaded the more the side bands that are created are reduced.  Being the Skeptic that I am I repeated his tests and confirmed his results.

dave
The Zu Denon is very much a "salt to taste" kind of cartridge when it comes to loading. When I used one it could indeed sound quite different when using 100/200/300/500/1000 ohms. And Zu will tell you there is no wrong answer here, just use what sounds best to you
Again: loading has no effect on the sound of a **low output** cartridge- it has everything to do with the stability of the phono preamp.

@intactaudio While I agree generally with Peter in this regard, I am suspect of the idea that loading causes the cartridge to track better in all cases. I have seen this where the cartridge was otherwise incompatible with a tone arm; a good example is a Grado in a Graham 2.0. The loading prevents the 'Grado dance' that can otherwise occur especially in lead-in grooves. However that is all about tone arm compatibility, and as I mentioned earlier, when you load the cartridge it stiffens the cantilever. So you will get different results in different tone arms! Peter wasn't being entirely scientific in this regard as his data was limited to one tone arm/cartridge combination.

I did repeat the experiment with a completely different setup and my results paralleled Moncrief's.   I would expect different absolute results with different tonearm / cartridge combos.  I did see a pattern of behavior that was consistent with both low and high compliance cartridges.

I do believe that the effect of the load is showing up as an adjustment of the compliance and would expect this to be a dynamic behavior.  

dave
I run my Benz Wood SL "unloaded" at 47K on my Pass XP15.  It sounds the most open, with airier highs, but admittedly I'd be hard pressed to tell the difference between 47K and 1000 ohms, maybe even 500 ohms.  Seems the Pass XP15 just isn't that sensitive to loading.  I suppose that's a good thing.  My brother has a Project Phono Box and the loading dial might as well be a treble knob!
Again: loading has no effect on the sound of a **low output** cartridge- it has everything to do with the stability of the phono preamp.
I don't understand this comment... a Manley Steelhead is unstable?  The Steelhead lets you switch loading on the fly and the tonal differences were easily audible.
I run my Benz Wood SL "unloaded" at 47K on my Pass XP15. It sounds the most open, with airier highs, but admittedly I'd be hard pressed to tell the difference between 47K and 1000 ohms, maybe even 500 ohms. Seems the Pass XP15 just isn't that sensitive to loading.
You are correct- when I've pointed this stuff out on other threads, Pass Labs phono section owners respond as you have.
I don't understand this comment... a Manley Steelhead is unstable? The Steelhead lets you switch loading on the fly and the tonal differences were easily audible.

If the loading is affecting the sound like that its a good bet that the phono section is sensitive to the resonant peak' RFI as I mentioned earlier. Now I should point out that MM cartridges do behave differently- if you have one of those then loading is critical IME moreso that LOMC. This is partially because MM cartridges do ring at audio frequencies if not critically damped. LOMC cartridges don't ring anywhere near audio frequencies- if you 'ring' them with a square wave the input and output waveforms look the same.


There are IMO/IME four parameters that have to do with phono preamp design:
1) enough gain with low enough noise2) accurate EQ3) resistance to RFI4) good internal stability
It is the last two on the list where many phono sections have problems. If you find for example that you get lots of ticks and pops even with new vinyl, this is a sign that the preamp has troubles with these last two parameters. Needing to have a low resistance load on the cartridge is another (keeping in mind that we are talking about LOMC); if the phono section is set up right 47K as a load will be found to work just fine, assuming that normal low capacitance phono cables are in use.

Seems like  most everyone else seems to hear differences with load changes.  Maybe by building a phono pre so quiet or with certain tubes, etc... kills the music from coming totally through.  

Dave brings up a interesting point and another variable which may explain why most people hear differences between loading.  You also notice he did not make make blanket statement about do this and your  home free!!!

I only thing I know for certain is there are so many things we do not know about energy.  And the only real way to know if you are reproducing something that sounds like Real music is to listen, change, listen, change, listen etc...!!!

I realize this is not building forum so you are at the mercy of manufacturer and the ad copy.  And being able to experiment with infinite amount of different resistors and capacitors to load your cartridge just right, is not in the cards, for most people.

Enjoy the ride
Tom
After meticulous Tonearm set up I have always just used the manufacturer's recommendation. Switching around on an ARC phono amp I can not make out any difference in sound quality.
Ralph, how does cartridge impedance affect all of this? I assume on a good phono amp not at all. If a higher load increases the motor's stiffness why wouldn't a cartridge track better at lower loads?
I forgot. How would this affect the resonance of the cartridge in a particular tonearm. It sound like lowering the load might lower the resonance frequency?
@atmasphere

Is there a measurement on Stereophile or whatever that will show if a phono stage has resistance to RFI and/or good internal stability?

Otherwise the only way to know is to compare the sound of a LOMC at say 300 ohms vs 47k, right?
Ralph, how does cartridge impedance affect all of this? I assume on a good phono amp not at all. If a higher load increases the motor's stiffness why wouldn't a cartridge track better at lower loads?
When one **increases** the load, the actual load resistance is lower. If there is less load, the resistance is higher.  That should answer your second question as well.
Is there a measurement on Stereophile or whatever that will show if a phono stage has resistance to RFI and/or good internal stability?

Otherwise the only way to know is to compare the sound of a LOMC at say 300 ohms vs 47k, right?
I've not seen Stereophile do any such measurements- which IMO suggests that whomever is doing the testing isn't paying attention to this parameter. So yes, trying the two different loading values is about the only way you can do it.


BTW, here is an excellent tutorial on this topic:http://www.hagtech.com/loading.html

This tutorial is seeing everything from the cartridge point of view and ignores how the phono section responds. But the resonant peak I've mentioned is obvious. Cartridge manufacturers often suggest a value for loading, but that is usually a general value and this calculator reveals why: the tone arm interconnect cable is playing a role (as well as the input capacitance of the phono section) and this value is an unknown. So the loading value often seen in the literature for a cartridge is really only a suggestion.


What I am maintaining is that if the preamp is properly designed, the resonant peak will be of no consequence to the phono section. Its pretty obvious that a peak like that if driven into excitation (which it often is by the cartridge itself) has the ability to overload the input of a phono section unless that phono section takes this issue into account.


Again, the presence of RFI or ultrasonic energy at the input of an active circuit can affect the way it sounds. As I mentioned earlier it can also affect the compliance of the cantilever of the cartridge. Jonathan Carr (of Lyra fame) and I had a conversation on this topic at Munich a few years ago- it was after a thread on this topic on which we were both active as on the What's Best Forum. He pointed out to me this issue of compliance- prior to that I'd not really thought it thru. Its a really good point because into 47k the cartridge might be doing X amount of work, but into 100 ohms it will be doing 470X **more** work, and that energy has to come from somewhere otherwise a new branch of physics is created :)

That of course will limit the ability of the cartridge to trace higher frequencies. But cartridge compliance is not measured with such low resistance loads, so when looking at the specs to see if a particular cartridge is going to work in a particular tone arm this issue can throw off the setup!




I agree that the load effecting the compliance is a plausible explanation for part of what is happening with loading but when it comes to "work" and tracing high frequencies the water becomes a bit more muddled.   It seems that moncrief pretty clearly illustrates and I have confirmed that loading a cartridge reduces the sidebands created from a 400hz + 4Khz test track.  This suggests to me that the stylus must be tracing the groove better if a more accurate representation of the original is seen.  Now you mention  with respect to a cartridge doing more "work"

That of course will limit the ability of the cartridge to trace higher frequencies.

I think the above is in relation to the idea posed that a lightly loaded cartridge will trace high frequencies better than a heavily loaded one because it is doing less work.  This seems at odds with the intermod findings WRT loading and I wouldn't be surprised if there is a point where a cartridge will become so loaded down that it does indeed mistrack high frequencies.  What I am interested in is the underlying explanation why a cartridge doing more work will necessarily have this "limited ability to trace higher frequencies"

dave


I bought the cartridge from Audiofeil ( sold via Audiogon) and was assured it was a good match for the VPI Scout that I bought it for. It was still pretty much brand new when I had it mounted on the Technics. In 2020, I plan to get the Dynavector DV 2X L cartridge as I owned the older model before and loved the sound. Do you think Audiofiel gave me a bum steer?

Since they gave you recommendations for VPI i am not sure what it correct or not, because i never owned a VPI with hteir tonearm. But i still own Technics tonearms and Technics turntables and for this arm Denon DL-103 is not optimal at all (like any low compliance cartridges). For example Dynavector KARAT23rs or KARAT17D2 are perfect for Technics tonearm because the compliance is much higher! 

In my experience dealers not always understand everything regarding tonearm/cartridge resonance and even about cartridge compliance. I remember how difficult for me was to get any valid information from ZYX dealers, they could not answer my questions regarding tonearm/cartridge matching, so i learned some stuff myself over the years. 

My advice for you is to try some of the very best MM cartridges on Technics turntable, you will be surprised how good an MM cartridge can be in comparison with more expensive and practically inconvenient (because of the retip) LOMC. if you need help with MM just ask me. 


What I am interested in is the underlying explanation why a cartridge doing more work will necessarily have this "limited ability to trace higher frequencies"
It will be stiffer, less compliant.
Great tutorial atmasphere! Everyone should check this out. There are several calculators for various factors including step up transformers.
You just plug in your values and hit the calculate button. My own rule of thumb has always been to follow the manufacturer's recommendation.


Dear @atmasphere  and friends: ""  and as I mentioned earlier, when you load the cartridge it stiffens the cantilever. ..""

""   It will be stiffer, less compliant.   """

both statement from you failed for something very simple: no explanation about, no explanation why that: less/limited ability to trace high frequencies by the cartridge.

This is not the first time you posted the same and never suppotr those statements when other gentlemans somewhere supports what they said as PM confirmed by @intactaudio  and certainly are my experiences too:

"""   He then goes on to show swept frequency responses of MC cartridges under varying loads showing minimal change in the frequency response.  

He then goes on to point out that loading down a cartridge has a sincere effect on the side bands created from 400hz + 4Khz intermod test track. He shows plots of different load situations and it can clearly be seen that the more the MC cartridge is loaded the more the side bands that are created are reduced. Being the Skeptic that I am I repeated his tests and confirmed his results.  """ 


Same gentleman intactaudio posted to you:  

"""   What I am interested in is the underlying explanation why a cartridge doing more work will necessarily have this "limited ability to trace higher frequencies"

and till now you decided not give an answer.


But other gentleman posted to you:


"""  It sound like lowering the load might lower the resonance frequency?  """


and again you did not give an answer.



In other thread where you and me participated a gentleman with a way very high technical knowledge levels that me and maybe than you posted  as an answer for your touted statements:

"""   why any of the purported effects of heavy resistive loading you state could be definitively true- certainly not on tracking which is demonstrably false based on IM tests on tracking performance that I have incidentally performed as a function of load."""

that engineer proved with technical math simulations/studies that what you " touted " is not exactly true and in that thread you did not gave an answer to his post.


It's impossible that the loading cartridge can really change the self cartridge tracking habilities. 
For that can happen practically you have to " stop " in some level ( high level. ) the movements of the ride stylus tip groove modulations where those groove modulations movements are generated for tremendous/very high forces down there between the stylus tip and the grooves.

Maybe in a cartridge with 15cu on compliance this must goes to at least half that compliance for that could happen and maybe not even with that lower compliance..


I think that at least the other gentlemans deserve that you give them the answers and obviously to me and all the gentlemans that posted in this thread.


I hope that this time you don't stay " dead silence " about like in other threads.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
Cartridge loading discussions were endless, are endless and will be endless...
To make it short, to dampen a cartridge means, you reduce their headroom, 
47kΩ is 'open', you can hear the cart purest, the way it was made, when 
your System is not up to the task to handle that (and most can't), you can 
dampen it down (some say it has to be done based on high frequency 
distortions but that is wrong). With one of the better Phono Stages you can hear 
it easily when you step down from 47kΩ it always becomes more slow 
and dull (but honestly a lot of Systems need that, the wonder word is: 
Compensation, with Cables you can do the same)
To design a Phonostage which is silent, not sensitive to hum or other 
influences, probably with higher gain (62dB and more) AND finally has to sound 
like music and not dead and lifeless (most do) ---> this is VERY difficult to do , 
the Designer really needs knowledge about that chapter. In the last 15 years I 
only heard 3 Phonostages which were able to solve that
- Klyne Phono 7
- Atma-Sphere
- J. Curl Vendetta
All the other countless designers will find endless reasons why their units run 
best with 100Ω or 125Ω or 165,37Ω or 358.5Ω -:) but at 
the end of the day, they can't do it better. It is the way it is.
Marketing can replace knowledge [and does of course and when it is repeated 
countless times, it becomes ---> A Fact :-)]
Years ago a lot of cartridge manufacturers wrote in their datas: recommended 
loading 47kOhm (Benz for example)....with the result, that the customers 
tortured their dealers that their Phonostages were not able to run with 
47kΩ (or they sounded simply awful with this setting, Levinson, XONO and 
so on), and they didn't buy the cartridge. 
No deal is the worst deal for a 'Dealer'
Now we have in the manuals: Recommended loading 100Ω -47kΩ 
The problem is solved now
That's High End :-)
Syntax,

you mention cartridges sound purest into 47K and dull into larger loads and if your phono stage isn't up to it you are in trouble.  

Mocrief suggests (and then supports with data) that the "dull" sound reported from loading a cartridge is simply the removal of high frequency distortions mistakenly perceived as detail.  He goes on to suggest that many accept added information not in the original to compensate for deficiencies elsewhere in the system.

These are two very different takes on the same topic and currently Moncrief's viewpoint is somewhat more plausible to me.  
Marketing can replace knowledge [and does of course and when it is repeated 
countless times, it becomes ---> A Fact :-)]

I 100% agree with the above.  Facts are objective, repeatable, and provable.  Attaching facts to a purely subjective experience can only sullen their beauty.  

dave

Syntax and intactaudio. There are a few other factors involve that help to explain these interactions. Your views are forgetting to take these factors into account. All this is explained nicely here  http://www.hagtech.com/loading.html. Depending on the inductive and capacitive loads there may be an advantage in higher load/damping which means lower resistance. This is shown very nicely at this site. There are certainly instances where running a low resistance (high damping) will roll off the frequency response prematurely but too high a resistance (low damping) can create huge high frequency resonance peaks that will overload a phono amp. Just running any MC cartridge at 47K is asking for it.  
Another issue. Brighter and louder are frequently mistaken as better sound. All this has been exhaustively demonstrated. If I boost volume on an identical source 1 db. People will mistakenly think it has better sound. Same for high frequencies. If I boost them a few db people will think it sounds better. People who are use to listening to a system that has the high end jacked will think a more naturally balanced system sounds dull and lifeless. Very few of us know exactly what our systems are doing. They have not run an impulse test and graphed it out. Even fewer of us have the ability to modify the frequency response of our systems in a controlled fashion to know what any given frequency response change maneuver will result in. This results in a classic case of the blind leading the blind. It's fine to have preferences but saying they are more right than someone else's preferences is inappropriate and quite possibly dead wrong.  
Dear @mijostyn : Almost always 100 ohms works really good even with phono stages with a low headroom ( but today designs comes with high headroom, no problem at all. ) PM is rigth and exist two " problems " as PM said at 100 ohms is not really dull but the sound sounds what is in the recording adding the less. That " open " sound reported for gentlemans loading at 47K like that kind of sprk and openess that are only added distortions for that cartridge loading value.

I always supported that kind of statement for many many years ( posted several times in this forum and with out know anything of PM comments. ). intactaudio is rigth about : ""   to compensate for deficiencies elsewhere in the system."""

The other issue is a bad phono stage design or a " terrible " TT/cartridge/tonearm set up or selection in between with wrong matchs.

@intactaudio  of course syntax's sytem is in trouble and that trouble comes from the phono stage design.

Btw, this is what we can read in the loading link you posted again:

""" 

As mentioned earlier, the peaking is best damped by lowering the load resistance. This is why MC cartridge manufacturers often request loading of about 100 ohms. The next plot shows the 5mH 10 ohm cartridge loaded with 200pF and a variable resistance. Note the 4.7k loading provides very effective damping while maintaining a bandwidth of over 100kHz. Too much damping with the 470 ohm load pulls the response down too quickly. Most MC cartridges have less inductance than this example (chosen to highlight the issue), and so the typical loading value of 100 ohms is usually quite reasonable. """


and something important is that the inverse RIAA eq. was not take in count for the calculations and the site disclosed it.


As syntax said loadin and MC always be an often asking subject because loading function as a " tone control " but the culprit or comes for a bad PH stage design or from each one of us ears and our knowledge levels about how the live MUSIC sounds and of course our preferences on what we like to hear.


Btw, I don't know you or intactaudio but I'm still waiting for the @atmasphere  precise answer/numbers on that high frequency lower cartridge tracking because the loading issue along that stiffen cantilever for it. I'm sure he will comes for.


Regards and enjoy the MUSIC NOT DISTORTIONS,

R.




Mijostyn,

The Hagerman site gives loading examples for what appear to be a typical MM cartridge where the resonances being damped are just outside the audio band.  This discussion has been about MC cartridges where the resonance in question is typically above 1 megahertz which is a very different situation.  The typical MC cartridge has around 1/1000th the inductance of an MM so enter 0.005 into the mH field of the calculator to see what we are discussing.  

I for one would love to see documentation of the ability of a cartridge to generate a 1MHz signal to excite this resonance.

dave
I think it’s analogous to “back EMF” that affects the interface between amplifier and electromagnetic speakers. The movement of the coil on the cantilever that is excited by the groove is not perfectly damped. Any spurious motion thus created would generate a voltage. The load resistor affects the degree to which the spurious motion of cantilever is damped out. Why is it hard to imagine that the damping force makes the cantilever also do more work?
But I’m just guessing pending an opinion fro Ralph or Dave.
I just read this review and thought of Ralph's comments:

http://www.10audio.com/aurorasound_VIDA_Prima.htm

Just being curious, I unloaded the Madake by switching the loading to 47k Ohms. WOW! The upper frequencies opened up and became noticeably clearer and with finer resolution. Update to my advice above, start your tests for the optimum loading setting with the MM (47k) settings.

The VIDA Prima and Pass XP-25 share an important attribute: they both sound best when the Miyajima cartridge is loaded at 47k Ohms. This suggests circuits that are designed to manage a MC cartridges’ tendency to sound better loaded, a weakness we refer to as “ringing”. Some of this artifact could be an issue with the phono preamplifier. The VIDA Prima does not seem to have any tendency to exacerbate ringing.

Dear @lewm : """ is not perfectly damped... "" almost nothing in audio is perfect. Where do you read what you posted not only that but about that sporious motion that stiffens the cantilever?

Everything in a cartridge quality performance is important in its design and building quality but the cartridge suspension is CRITICAL and you can ask Ortofon about and you will know what they have to say in that issue.

The problem is that for years atmasphere posted here and in other net sites the same with out shows any single foundation ( numbers/charts, white papers, etc. ) that can attest that the cartridge lost high frequency tracking abilities ( " it can also affect the compliance of the cantilever of the cartridge. " """ will limit the ability of the cartridge to trace higher frequencies .."""   These are statements he posted.) and till we have true facts about by his side what he said on the subject is just false and with no true sense of that lost high frequency tracking ability by the cartridge. Maybe makes sense to you, not to me.

R.


"[Lowering the R_load]... of course will limit the ability of the cartridge to trace higher frequencies. "
I fail to see it either, unless the below reasoning is wrong. I think of a simple cart model as a damped harmonic oscillator, excited by an external force of freq. f (the movement of the diamond induced by tracing the groove with a tone of freq. f). Loading the coils creates a current flow in them, which results in a damping force, opposing the movement of the coils in the magnetic field of the pole pieces. This is just a well known electromagnetic breaking force, proportional to the velocity of the movement (in turn proportional to the frequency) and inversely proportional to the R. It is just plainly ~f/R, like any other linear damping force. It adds to the total damping force, acting on the cantilever (the rest comes e.g. for the mechanical damping in the suspension). Lowering the R, just lowers the output across the entire spectrum but the nature of the output (its functional dependence on f) does not change at all. No additional damping of higher frequencies beyond the normal behavior of a damped oscillator. Just the damping coefficient increases.

I’m much more intrigued by @intactaudio dave’s observations of lowering the IMD. Have you tried plotting the IMD vs. R dependence?
Cheers


i have a Kiseki Purpleheart mounted on an SME 312S feeding a Pass XP 17. I don’t know the capacitance of the included tonearm cable, though I may try to find that out. I’m pretty sure that when I did the tonearm/cartridge resonance calculation, the value was in range, something like 10cu. I had been playing around with all manner of load settings, mainly in the range of 100 to 452 ohms, and had settled for the most part on 452, though I sensed something was off, not a lack of high frequencies per se but a sense of harshness. When I increased the loading value to 1000 ohms, the sound became smoother and had better spectral balance. FWIW, 1000 ohms is in the 800 to 1000 ohm range recommended adamantly in Bob Levi’s Purpleheart review, as opposed to the Kiseki recommenced 400 ohms. His equipment is different than mine however. Still, it sounds like stereo5 made the same conclusion as me with a totally different setup. I don’t want to generalize here, but it’s tempting to think that these lower load recommendations are not optimal in many situations.
I’m much more intrigued by @intactaudio dave’s observations of lowering the IMD. Have you tried plotting the IMD vs. R dependence?

not yet.  coming up with a concept for a test methodology to do this is not an easy task and then bringing that concept to fruition is equally as difficult.  Collecting the information in a meaningful way is one thing and presenting it is an easy to understand fashion another.  Moncrief shows the results fo both a JVC cart and an EMT and simply showing graphs give a quick visual result of the pattern but having a better understanding of that pattern would be nice.  

I'm thinking that the source tone is a 4K + 400hz signal and normalizing the 4K fundamental for various loads and plotting the following frequencies (7200, 7600, 8000, 8400, 8800) against load should be informative.

dave




I for one would love to see documentation of the ability of a cartridge to generate a 1MHz signal to excite this resonance.
Quite simply it does not need to! Audio energy can cause the excitation. A resonant circuit can be driven into excitation with a single pulse; it should be no surprise that on-going audio signals can do this as well.
Dear @atmasphere and friends: "" and as I mentioned earlier, when you load the cartridge it stiffens the cantilever. ..""

"" It will be stiffer, less compliant. """

both statement from you failed for something very simple: no explanation about, no explanation why that: less/limited ability to trace high frequencies by the cartridge.
I would have thought that the reason for the reduced compliance (stiffer cantilever) would have been obvious! A cartridge is a simple magnetic motor/generator, just like a dynamic microphone or loudspeaker, in that a coil has an audio signal transduced into it by a magnetic means- either by moving the magnet with relation to the coil (MM) or moving the coil in relation to the magnet (LOMC). It is easy to demonstrate this principle with a woofer of a loudspeaker with the grill removed (dynamic speakers operate on the moving coil principle of course). With nothing connected to the loudspeaker, simply depress the woofer cone and see how easy it is to move. Now short out the speaker terminals and do it again. You’ll find that the woofer has become much stiffer! This is exactly what happens with a cartridge as the modus operandi is identical.


As I mentioned earlier, if this were not to happen, a new branch of physics would thus come into existence :) because it would violate Kirchhoff’s Laws. The operating principle is similar to how motors and generators work so you can study them as well. In short, its impossible for a cartridge to drive a lower resistance load and *not* have a stiffer cantilever!
This is just a well known electromagnetic breaking force, proportional to the velocity of the movement (in turn proportional to the frequency) and inversely proportional to the R. It is just plainly ~f/R, like any other linear damping force. It adds to the total damping force, acting on the cantilever (the rest comes e.g. for the mechanical damping in the suspension). Lowering the R, just lowers the output across the entire spectrum but the nature of the output (its functional dependence on f) does not change at all. No additional damping of higher frequencies beyond the normal behavior of a damped oscillator. Just the damping coefficient increases.
I think you might be over-thinking this.

You got most of this right, right up until your conclusion. Think about a generator, one with no load and one with a load, which will be harder to turn? By your logic above (if I’m reading it right) somehow the loaded generator is easier to turn, which certainly isn’t going to happen. I think where you’re getting into trouble is the idea that the output goes down with reduced R load, which it does. The problem is: a certain amount of energy is used to make the stylus move. Where does that energy go? It is of course applied to the input load of the preamp in the form of a voltage. Now if you decrease the voltage by reducing the R load value, where is that same energy going? The Law of energy conservation says it has to go somewhere! It does not just ’vanish’. It is dissipated in the load and also by the cartridge coils themselves, both in the form of heat. But I think you will find if you do some measurements that the output does not go down as fast as it appears you are thinking. This is because the stock 47K load is easy to drive and the output of the cartridge will stay pretty constant until the load is decreased to some point below 10x the impedance of the cartridge; IOW probably less than 100 ohms.


Hey Ralph,

this is where we got last time we had this discussion.
Quite simply it does not need to! Audio energy can cause the excitation. A resonant circuit can be driven into excitation with a single pulse; it should be no surprise that on-going audio signals can do this as well.

I would like to see some documented proof of this or point me to a way to measure it. I have no doubt that an unstable phono will have problems with spurious HF info but I do not see the cartridge ever generating anything in the megahertz realm to excite this.

I do not see anyone debating that a loaded MC cartridge will stiffen its suspension, what I think is up for debate here is that this stiffening of the suspension will lower the cartridges ability to accurately trace high frequency info.

The 800 pound primate hiding in the corner here is the trend for some to insist that a cartridge is inherently a current generator and should feed a current amplifier for optimal performance.  This necessitates the cartridge driving a near dead short which by your reasoning would have a sever impact on the HF tracking ability.

dave


I have no doubt that an unstable phono will have problems with spurious HF info but I do not see the cartridge ever generating anything in the megahertz realm to excite this.

I do not see anyone debating that a loaded MC cartridge will stiffen its suspension,
The cartridge will not generate MHz output. But think about it this way- if that resonance is out there and it never goes into excitation, this conversation would be moot. But obviously it does and here we are.
Raul has been challenging me on the stiffer cantilever thing. So I think we have to get past that first.
You can certainly run a cartridge into a near dead short. Its output will lower of course. But now that you point this out, the reaction by the cantilever would seem to be a downside. What is needed right about now is some sort of measurement, perhaps a sweep tone from 20 to 35KHz so we can play a cartridge back and see how the loading affects it. 35KHz is probably overkill but should be well within any modern LOMC cartridge and phono section. Its been on the record side for decades if my Westerex 3D is any indication. But to my knowledge other than conversation with others in the industry and my own research on the matter (I attempted to design a loading box that would sort out the correct loading for any cartridge about 20 years ago) I've not seen any actual measurements. Its for dead sure that stiffening the cantilever will have adverse effects in some situations, but in some cases it could help. One example of that is a Grado cartridge on a Graham 2.0 unipiviot. Normally the mismatch between the two results in something called the 'Grado dance'. But I've seen that with loading this dance is eliminated.
I think you might be over-thinking this.
@atmasphere  I doubt it, I'm quite ok with physics and I apply it to the situation.
You got most of this right, right up until your conclusion. Think about a generator, one with no load and one with a load, which will be harder to turn? By your logic above (if I’m reading it right) somehow the loaded generator is easier to turn, which certainly isn’t going to happen.

Seems you did not understand what I wrote: lower R presents obviously more breaking force, opposing the stylus movement. This is the electromagnetic induction law in action: the current (flowing through R) creates the magnetic field that opposes the stylus movement. This force behaves like ~f/R.
I think where you’re getting into trouble is the idea that the output goes down with reduced R load, which it does. The problem is: a certain amount of energy is used to make the stylus move. Where does that energy go? It is of course applied to the input load of the preamp in the form of a voltage. Now if you decrease the voltage by reducing the R load value, where is that same energy going? The Law of energy conservation says it has to go somewhere! It does not just ’vanish’. It is dissipated in the load and also by the cartridge coils themselves, both in the form of heat.
Just to be precise, the energy is not presented in a form of a voltage because voltage alone cannot perform work. The energy is presented in a form of a heat, dissipated in the combined resistance of the circuit (R_load, the coil DCR, the cables etc), caused by the induced voltage applied to the resistance. This is ok. The question is so what? To speak of energy conservation, you have to look at all the forces acting on the stylus:
- the driving force, coming from the diamond tracking a rotating, modulated groove, say at freq. f; this force is the source of all the energy flows- the restoring force of the suspension- various damping forces, including the electromagnetic one ~f/R

In a simple case of a linear suspension, you can solve it (for the speed of the stylus as the signal is proportional to it) and you will see that the movement has two components:
1) the transient, exponentially decaying self oscillations of the stylus; the frequency is the usual cart-tonearm combo but decreased due to the electromagnetic damping; the decay time is inv. proportional to the damping so ~R in the EMF part
2) the steady state, the forced movement with the freq. f, dictated by the tracked groove;this is the signal we want; the amplitude of this movement will have an R dependence too

The only *qualitative* change in R can happen is in the 1st, spurious part. Lowering  the R changes the suspension character from underdamped to critically damped to overdamped. But this is not the signal we are trying to get! This is an artefact added to the real signal of freq. f.
Of course if the motor is so weak that the stylus tracing a HF track into low R will make it slow, we are in trouble but let's assume a healthy TT design.

But I think you will find if you do some measurements that the output does not go down as fast as it appears you are thinking. This is because the stock 47K load is easy to drive and the output of the cartridge will stay pretty constant until the load is decreased to some point below 10x the impedance of the cartridge; IOW probably less than 100 ohms.

I suspect you are trying to describe a behavior of the 1/R function. Yes, far from zero it flattens out so changes say 1k to 47k can be negligible, but the closer to zero the steeper the changes.

Summarizing, you seem to selectively use the bits of the whole picture of the stylus motion and draw conclusions from them, like the fact that lower R changes the compliance, but you completely neglect that there is a very strong driving force here coming from the rotating platter, and this is the force setting the stylus into the motion.

lower R presents obviously more breaking force, opposing the stylus movement. This is the electromagnetic induction law in action: the current (flowing through R) creates the magnetic field that opposes the stylus movement. This force behaves like ~f/R.
This is what I've been maintaining all along.
Just to be precise, the energy is not presented in a form of a voltage because voltage alone cannot perform work. The energy is presented in a form of a heat, dissipated in the combined resistance of the circuit (R_load, the coil DCR, the cables etc), caused by the induced voltage applied to the resistance. This is ok. The question is so what? To speak of energy conservation, you have to look at all the forces acting on the stylus:
- the driving force, coming from the diamond tracking a rotating, modulated groove, say at freq. f; this force is the source of all the energy flows- the restoring force of the suspension- various damping forces, including the electromagnetic one ~f/R
In a word, yup.
The only *qualitative* change in R can happen is in the 1st, spurious part. Lowering the R changes the suspension character from underdamped to critically damped to overdamped. But this is not the signal we are trying to get! This is an artefact added to the real signal of freq. f.
Of course if the motor is so weak that the stylus tracing a HF track into low R will make it slow, we are in trouble but let's assume a healthy TT design.

Since we have been in agreement all along on the first two bits, maybe its this last bit that is the stumbling block. I used to load MM cartridges to critical damping by simply ringing the cartridge/cable combination with a square wave and observing the resultant output and taming it with a loading resistor. MM cartridges have a lot more inductance so its easy for that inductance to ring. But attempts to do this with LOMC failed, simply because with any loading I could not detect anything other than a nice looking square output since the inductance is so low. So I am challenging the idea of critical damping of the mechanical aspect of the suspension, not because I don't think it can happen but more because I'd like to see the evidence. Its an interesting idea- I am assuming that the electrical damping used to do this is similar to a shock absorber in a car; with the right amount the stylus in better contact with the groove, just like a shock absorber keeps a wheel on the road.


My exposure to all this is through phono preamplifier design; about 35 years ago I discovered that the phono section itself can contribute to ticks and pops. I discovered this serendipitously but once I understood it was real it was then a matter of sorting out why.  And the answer (as I have mentioned earlier on this thread) has a lot to do with this ultrasonic/RF resonant tank circuit that I've been talking about. I've also noticed that while I can cut a 35KHz groove on my Scully lathe, depending on loading you can't always play it back, depending also on the cartridge.


So now I am curious- at what frequencies did you make your measurements?  At this point it appears that the taming of the resonant peak requires a different value as opposed to that which might tame the cantilever; the two aspects are caused by entirely different mechanisms. However, **any** resistance in parallel with a tank circuit will detune it; for most phono sections to be happy the detuning must be enough to kill the tank circuit altogether.
I too use 1000 ohms on my Ortofon.....experiment and find your own perfection.