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.
NO, I did not only ask for evidence and not more bla, bla like your bla, bla in your last post. Btw, I know for sure the effects of damping in HF and over the FR. This is not the issue and stop to go " around and around " that only saids you are a lier as I posted till shows here that evidence ( like PM or Palmer. ) with no bla, bla.
And please the " victim " role is not for you , forgeret. If you have nothing to show then why posted again: incredible ! !
I’m not attacking him only asking for true proof/evidence of that "
limit trace " that he spreads every where with out shows the evidence as
foundation for.
Just to be clear, yes, Raul, you attack me at every opportunity. This is well known by many others on this forum.
With regards to your need for proof- I recommend that you study the effects of damping on high frequencies. It is clear from your posts that at this time you have not done so.
I’m not attacking him only asking for true proof/evidence of that " limit trace " that he spreads every where with out shows the evidence as foundation for.
@lewm : ""
I am running them at 47K ohms routinely now. I find the sonics to be more open and airy that way, and I feel no impulse to move back to the more typical 100R value. """ "
" them........routinely now.No impulse to move back...."
and now you said: one cartridge by accident.No problem.
No, you have a big problem. Not me. Wanna go back and forth on this? I cannot imagine why you think I hit on you simply by pointing out a possible mechanism for one effect of loading on an MC cartridge. I was trying to make a neutral contribution to this discussion, but I realize it may have seemed to you that I was taking Ralph's side against your attack. I really wasn't. Thanks for the correction on the recommended loading for the Lyra cartridges per the Lyra website, but is it not the case that Jonathan Carr has suggested 47K ohms for LOMCs, in this forum? If I'm wrong there too, I would like to know about it. In any case, I am far from "recommending" a 47K load. As you may recall, I discovered that I liked 47K for one of my LOMCs by accident, because I forgot to adjust the load at the phono input one evening before playing music. So I reported my surprising result here. Unlike yourself, I do not try to tell other people what they should do. And the cartridge was not riding in either of the two tonearms that I own and you hate, on the evening when I made the observation that there is some merit to 47K loading in my system. And why does THAT make you so furious?
I am probably crazy for jumping into this conversation, but boldly going in; there is a lot conversation with a lot of experience on this subject, but from a engineering perspective, actual analysis can be pretty light, and the accuracy of vendor data often a best guess.
For the mechanical resonance issue, this article that you can download is a good detailed explanation: "On The Mechanics of Tone Arms" Dick Pierce Professional Audio Development, Jan-05. But, it also begs the question - how does each vendor measure and report mechanical compliances. Recently I was reviewing test data for some cartridges, and a noted vendor reported a cartridge compliance of 16, but when tested, it measured 23; that can be a big difference. And, depending on your particular setup, the tonearm compliance can be different from the vendor data. If, you are 9-10Hz calculated, then you have a pretty good margin for error. But, if you are at the margins, maybe not; so a test record to verify is recommended. Unfortunately, electrical can be a bit more complicated.
For the electrical resonance/loading issue, this article on TNT http://www.tnt-audio.com/sorgenti/load_the_magnets_e.html; does a closed loop electrical analysis, but then shows by testing that the actual measured results do not follow the simple electrical closed loop model. However, this article "NEW FACTORS IN PHONOGRAPH PREAMPLIFIER DESIGN" TOMLINSON HOLMAN, 1975, clearly addresses multiple pre-amp design factors that can effect the overall cartridge-preamp performance; so the skill of the pre-amp designer and the pre-amp has a lot bearing. Add to this, that the vendor reported cartridge data may not be correct. When I was reviewing test data for some cartridges, a noted vendor reports a cartridge output voltage of 5.5mV, but it measured 10mV; that is a big difference.
In summary, and somewhat amusingly, here we are in the 21st century, all full of metrics and big-data, and we are still trying to predict with accuracy how an over half-century technology will perform. So, with the data we have, we take our best guess as to what will work. But, in the absence of actual integrated data - cartridge-tonearm-cable-preamp, which is surprisingly limited, we are still left just listening to the music; and making adjustments and decisions based on what sounds best. An imperfect system that with patience can produce near perfect sound, one of those "freakin" miracles :).
On my post to which you responded (today at 1:18 pm), I was typing on my iphone, on which I am prone to errors. Perhaps the grammar of my sentence confused you, and I was unable to edit it because Dave (Intactaudio) posted before I could make a change. So, my sentence, "But you have absolutely no grounds to say that a 47K load on a LOMC cartridge sounds best to me in my system in my house with my equipment", should have been re-written to say that you have no grounds to doubt my observation that 47K sounds best, in my house, in my system, with my cartridge. (I think at the time I was using either my Koetsu Urushi or my ZYX Universe.) I certainly did not mean to deny the fact that I did make that observation. Yes, that is what I have found with one of those two cartridges. As of today, I would say that loads above 1000 ohms, up to 47K ohms, sound about the same, but below 1K sounds less "real", more closed in. I’ve never checked the actual frequency response. Nor did I ever claim that high frequencies were actually attenuated with loads below 1K ohms. I am reporting a subjective judgement of what I hear on music. So keep your shirt on.
By the way, I should add that when it suits you, you are quite willing to accept J Carr as a guru. Yet JCarr is one of many of the cognoscenti who also suggest 47K as a load for LOMCs, especially the Lyra cartridges he designs. So now, what’s your problem?
Dear @lewm : """ But you have absolutely no grounds to say that a 47K load on a LOMC cartridge sounds best to me in my system in my house with my equipment. """
Really? , well you have a short time memory even of what you post. Here is what you posted about, your words not mines:
""" But I have lately found that even LOMC cartridges sound their best when the cartridge is essentially un-loaded, at 47K ohms. The treble is more "open" and airy. Dynamics are also improved vs more traditional values of load resistance. """
and you followed:
""" I only recently experimented with reducing the load on my LOMC cartridges, which is to say I am running them at 47K ohms routinely now. I find the sonics to be more open and airy that way, and I feel no impulse to move back to the more typical 100R value. """
In the other side, yes I know that there is no reason for you can have a matter/worry that lost of credibility. Who cares about?, certainly not me ( not shock for me in any way. ) and obviously not you but after those posts by your self finally I can understand why you almost " die " for the FR/Dinavector ( terrible/horrible. ) tonearms and is because you love those kind of distortions. Good for you. In my case I like different kind of distortions.
Raul, it may shock you to learn that my credibility with you or lack thereof is not a matter that concerns me a great deal. We disagree on many many things, and you know that. But you have absolutely no grounds to say that a 47K load on a LOMC cartridge sounds best to me in my system in my house with my equipment. Your system is almost a direct antithesis of mine to begin with, and you have never been in my house. Here it is not even a matter of disagreement. I seek understanding, and I am getting some understanding by reading the posts of Palmer, Ralph, and Dave Slagle. Perhaps I could thank you for being provocative, so I can learn from those other persons. The only thing I can be said to have contributed to this discussion is the concept that there must be a back EMF generated at the coil of a cartridge, just like the back EMF that is generated at the coil of an electromagnetic loudspeaker. There seems to be general agreement that that is the case. After that, I am all ears and I do not pretend to be a source of knowledge. Yes, Ralph is my friend, and so is Dave. That has nothing to do with anything.
Useless with you. Keep talking with no true evidence of that " limit cartridge trace/tracking " due to loading changes. Only your bla, bla that at least for me is not enough because I have very low understand to with out evidence.
@lewm did you know how much " force " do you need to apply/need/ at the base of the cantilever to really impedes at the stylus tip position its free movements, a tiny movement? no? then what are you talking about? yes? please let us know?. and please no bla, bla like your friend but true evidence. Btw, do you know the " power forces/inertia " generated at the stylus tip when ridding the grooves at 33/45 rpm and what " force " is need it to " limit the trace " of the stylus tip to track when appliyed that force/loading at the other end of the cantilever?
For the five time in this thread: Palmer is the only gentleman that did it his technical job where he found out no single evidence of that " limit trace " by the cartyridge loading. Is the only gentleman that posted true evidence but obviously as your friend you don't beleive him with out reason by your part.
Btw, you participated in that " party " of your friend and you was dancing with emotion when posted that you preffer listen to your MC cartridges at 47K ! ! From that same time/moment your credibility with me in that specific regards goes down/falls.
Dear @atmasphere : please don't change the words. You posted several times:
"" will limit the ability of the cartridge to trace higher frequencies .."""
where are the evidence of that " limit to trace ".
Damping effect is one thing and trace/tracking isssue in the cartridge is a way different subject.
I thinkthat now we are talking of different issues. Palmer proved to you and all that there is not that such " limit trace/tracking " in the cartridge abilities and in that thread no one including you had nothing on hand ( evidence. ) to refute the Palmer true facts:
""
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 . ""
and in your last post in this thread now you are changing and talking only that : "
"
damping limits high frequencies ..." when for years you said " trace " ( including in this thread.
Btw for those gentlemans that don't know or forgot whom is Palmer here what he posted about in that thread when some one asked for:
"""
may not be a renowned Audio Designer, but I am a somewhat renowned IC designer with credits that include cell phone transceivers and high performance opamps.
I focused on high performance high speed amps like the AD843, 845 (at one point an audio darling), 846 (also a transimpedance design with some very interesting design aspects that I gave an ISSCC paper on) etc. etc. mostly using a complementary bipolar process that I helped develop that I believe was also used in the AD797. I also did things like designing the FET based AD736/737 RMS-DC converter and others. I moved on to more RF, disk drive read/write, GSM, CDMA etc. transceivers, signal processing, PLL and DSP designs .."""
He was a leader team at Analog Devices and like all the engeenering gentlemans that works as a leaders in those kind of companies ( in the past National and today B&B/Texas Instrument and the like. ) Palmer has not only a top electronics/electrical knowledge levels and skills and tools where belongs his opinion foundations. Extreme high credentials.
He worked too in UK in Decca in the recording overall production and then retired and as free-lance is an advisor of manufacturers and through specific internet forums and individual persons that needs his services.
Where exist that evidence true evidence about because I don't see the foundations for your several years statements.
I see that you don't. But if I tell you that the sky is often blue, do I need to provide evidence, such as what 'blue' looks like? This is a similar problem; one based in engineering inherently understands that damping limits high frequencies.
"" will limit the ability of the cartridge to trace higher frequencies .."""
""
to simply say that by causing the cartridge to drive a lower impedance it will of course be less able to trace higher frequencies. ""
You said: "
it will of course ..". Where exist that evidence true evidence about because I don't see the foundations for your several years statements.
@intactaudio already posted evidence coming from IAR with evidence that tell us a way different " thigs " that what you support.
My post where you said I lost the " road " ( or something like that. ) was only an example where if we have a room/system with high resolution and low distortions levels we can be aware of what damping in the tonearms can do or can't does.
Damping makes at least two things: " cleans " the frequency range extremes that permit that we listen more MUSIC and less colorations/distortions/resonances with out losting recorded information. I could think you own that kind of room/system and enough first hand experiences with nera field listening of live MUSIC so your ears tell you for sure what I'm saying and if not then you are in trouble.
So damping it's not a " bad " move but a very welcomed parameter/characteristioc for a way better MUSIC enjoyment, to stay nearer to the recording and nearer to live MUSIC.
In that thread that I mentioned you participated, Palmer posted:
"""
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. While mechanical impact does occur as a result of electrical load- there is some back emf necessarily generated by the signal current that affects the mechanical motion, but a quick back of the envelope calculation using Lenz's law and the 10uH cartridge suggests a 2 orders of magnitude difference between the generated signal and the back EMF for a 100 ohm load at 20kHz- certainly not enough to cause tracking issues I would think. As for the rest, well, take the Madake for instance- the resistive load that people (reviewers) claim is best literally varies by nearly four orders of magnitude! I load mine with 60 ohms (as do many users) and I find that the resolution and dynamics is excellent while maintaining a natural timbre, tonal balance and micro/macro dynamics while not creating the unnatural e """
Some one in that thread questioned about was not EMF and Palmer gave this answer:
" Yes, it really is back EMF- it's calculated using Lentz's law and is a consequence of Faraday's Law of Induction and it occurs as a result of the change in current through the coil- that's where the frequency dependent term comes from (the derivative). The term is subtracted from the voltage generated by the cartridge and in that way it acts to reduce the output voltage and hence the current, so there's a degree of negative feedback. I chose to use the full inductance rather than the MC inductance alone as a way to add a bit of correction for the physical displacement of the stylus/cantilever/coil that occurs as a result of the generated force. I did it that way as I don't believe that true reciprocity occurs and I have no idea what the losses are. The "gain" can be scaled to increase the mechanical feedback- for example the value of multiplier for the s term in the feedback could be increased to Icart*1.5 for example. What I actually calculate is FBvoltage= k.Lcart*Icart*s, where K is the scale factor mentioned above (a default of 1), s=jw as usual, Lcart is the extended inductance and Icart is the actual cartridge current in the coil which I measure using a very small R as sucky LTspice doesn't include the right components to let me do it easily. """
Raul, with due respect, I don’t think you took the time to understand what I wrote about damping. Since then, Ralph, Dave, and a third person have pretty much corroborated my idea, although all 3 explained it at a more sophisticated level. Thanks to them.
no one never reported that a loading change or a 100 ohms load in a LOMC cartridge produce that tracking/trace HF problem ! !
To be clear, I have maintained and as we've seen on this thread, any damping will result in less HF response. Any LOMC cartridge these days has bandwidth far in excess of 20KHz; I can reproduce 35KHz sine waves I cut on my Westerex/Scully cutter and lathe system with a Grado Gold which is a MM cartridge which inherently has less bandwidth that LOMC. Since my cutter is bandwidth limited to 42KHz to prevent excess power from damaging it (this due to the pre-emphasis curve which boosts high frequencies at 6dB/octave) I've not been able to cut higher frequencies to see how high LOMC cartridges can really go, but I am certain that they can easily go past 60KHz.
I have not maintained as Raul claims that there will be a 'tracking/trace problem'; in fact I've been very careful about my use of English (not Raul's first language) to simply say that by causing the cartridge to drive a lower impedance it will of course be less able to trace higher frequencies. I've not said what those frequencies are. And I've also maintained that this is an area that warrants further study.
Raul has created a Strawman argument (and being a logical fallacy, therefore a false argument) that I've been saying that loading the cartridge leads to mistracking. I've not said that at any time; its my assumption that Raul's use of English not as his native language has led him in this manner.
Dear @bydlo : He is changing as the thread goes on because the main subject is that he posted:
"" will limit the ability of the cartridge to trace higher frequencies .."""
" to trace " not attenuates and that " limit the cartridge abilities on HF range is what I’m questioning to him and asking for evidence true evidence ( for many years now. ) on it because in any internet audio forum no one and I mean it: no one never reported that a loading change or a 100 ohms load in a LOMC cartridge produce that tracking/trace HF problem ! ! I had not never with any cartridge in my systems in the last 30 years with different phono stages and different loads impedances.
No one is questioning the electromagnetic damping but does not exist that trace/tracking problem because of it.
I was not whom posted about trace/tracking issue but him and he continue spreading that inexistent behavior from several years now. Go figure.
Alas this article is not available online but if you go to the IAR website it states Issue #5 can be purchased. I got my copies off of Ebay when I was pointed to the topic.
I said in proper design it is obviously possible to reach a neutral balance and this is what we all do adjusting the load
I think most of us agree that adjusting the load of an MC cart does have some effect on the sound. It is the cause of what we are hearing is that is up for debate. As it stands now I think the quoted text above sums it up pretty nicely and I find it interesting that outside of Moncrief, historically I have yet to see mention of this.
@intactaudio As I said in proper design it is obviously possible to reach a neutral balance and this is what we all do adjusting the load. Is the article available online? In general, there are dozens of situations where a wise pre-loading linearizes a mechanical system. Think e.g. of a motor, where a pre-load helps to smoothen out coging
Ok, so if by tracking problems at HF you mean attenuated HF then I agree. But this behavior applies to any damping, also purely mechanical, not only to electromagnetic.
The first thing Moncrief does in his article is to do a frequency plot of the cartridge with the two different loads he did the IM sweeps of. This was to show that the frequency response did not appreciably change to rule out the "old wives' tale" of loading damping a rising response inherent to MC carts.
But damping of the mechanism (cantilever and suspension) is a different matter, and its pretty safe to conclude that if it is damped, high frequencies will be attenuated.
Ok, so if by tracking problems at HF you mean attenuated HF then I agree. But this behavior applies to any damping, also purely mechanical, not only to electromagnetic. The simplest damping is a force proportional to velocity of the cantilever movement. For periodic movements this means proportional to the frequency, so the damping force is increasing with the frequency of the played groove. Electromagnetic damping is just an example of this type of force. And this is what anyone who has ever played with loading hears - lower R = less HF, more pronounced LF. The question is so what if at the end you can reach a natural balance? If you cannot, sth is wrong or substandard.
But I’m not sure how important this is. If the cartridge is properly set up in the arm and the arm is able to track the cartridge correctly, **and** if the phono preamp is unresponsive to RFI and is also inherently stable, then IME the stock 47K load has yielded the best results. I do think its an interesting topic though and think it bears more research.
Again, I think this the last sentence is more of a personal preference than any rule. I do not see anything bad in designing a cart in a such a way that it relies on a certain load resistance to help mechanically damping the cantilever.
I listened to all them with and with out the damping mechanism and differences are not small.
Damping mechanism?? If you are talking about the damping trough on the arm, you have missed the point of the conversation between @bydlo and myself entirely.
But what I meant is the mechanical damping of the stylus, not electrical damping of the LC tank.
Yes. If you pass a squarewave through an inductor, the more inductance there is the more it will ring; If you then place a resistance in parallel with the inductor this will cause it to ring less. When the resistance is the right value, the resulting output signal will be the closest you can get to a square wave. This resistance value is the 'critical damping' value for the inductor.
But LOMC cartridges really don't ring at audio frequencies. Now we can conclude from this that the damping of the coil is irrelevant except for the tank circuit, and the latter is of no importance unless the phono preamp has troubles with RFI at its input. But damping of the mechanism (cantilever and suspension) is a different matter, and its pretty safe to conclude that if it is damped, high frequencies will be attenuated. There are plenty of examples of this.
But I'm not sure how important this is. If the cartridge is properly set up in the arm and the arm is able to track the cartridge correctly, **and** if the phono preamp is unresponsive to RFI and is also inherently stable, then IME the stock 47K load has yielded the best results. I do think its an interesting topic though and think it bears more research.
I read all your posts and after several years you
never posted true evidence/facts ... You can do it very simple: take 2-3
LP tracks and give us as examples of your posts ... bla, bla, bla, etc is not enough with out true foundation in your statements. Why
don't give us those LP examples? easy to do it ... that's why insist that you bring here those
facts. Please no more bla, bla but facts that we can corroborate it.
No one here is obligated to conduct any tests on your behalf. Please feel free to conduct your own tests, though, and share your results with the group.
Dear @atmasphere : Really? because I read all your posts and after several years you never posted true evidence/facts that can tell us that " cartridge limit trace of high frequency ".
You can do it very simple: take 2-3 LP tracks and give us as examples of your posts and in this case we can have first hand experiences about because till today in no single audio forum in the web no one and I repeat no never posted that kind of trouble.
With all respect: bla, bla, bla, etc is not enough with out true foundation in your statements.
Why don't give us those LP examples? easy to do it. Of course that we need to know the different loads you try it and with which of those loads " things happens ".
I think that many gentlemans as me already made it that kind of tests and that's why insist that you bring here those facts. Please no more bla, bla but facts that we can corroborate it.
But the inductance of a low output moving coil is so low
that resistive damping has little effect, as in a nutshell the inductor
does not ring at audio frequencies or anywhere near them
But what I meant is the mechanical damping of the stylus, not electrical damping of the LC tank.
You followed posting your opinion and some " answers " but as in the
fast you just followed failen to prove the MAIN SUBJECT under debate
that you stated in this thread:
""" will limit the ability of the cartridge to trace higher frequencies .."""
Actually I explained that in some depth. I recommend you go back and read my posts and those of intactaudio and bydlo again.
Dear @atmasphere : You followed posting your opinion and some " answers " but as in the fast you just followed failen to prove the MAIN SUBJECT under debate that you stated in this thread:
""" will limit the ability of the cartridge to trace higher frequencies .."""
You don’t have any teue facts/measurements that can prove your statement but Palmer in the other thread I mentioned and that you, Al and JC participated measured and told you that what you say is FALSE:
""" 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."""
Palmer 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 , I think because you have nothing on hand in that specific regards.
In the Hagermann link you posted you can read:
""" 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 """"
@bydlo posted:
"[Lowering the R_load]... of course will limit the ability of the cartridge to trace higher frequencies. " ( this is what you posted. ) and his answer:
I fail to see it either,
@intactaudio
""" 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. """
Try to stop go " around and around " and go out of that circle where you are " trapped " by your self and give a direct measured answer to the main subject debate: limit cartridge trace high frequency.
Regards and enjoy the MUSIC NOT DISTORTIONS, R.
PS: I'm not pushing you as you posted. Things are that I'm asking you this questions for a few years now with no answer at all, a precise answer with out " circles ".
Electromagnetic damping due to a low R is actually quite an attractive (at least on paper) way of damping.
I agree, it is. But the inductance of a low output moving coil is so low that resistive damping has little effect, as in a nutshell the inductor does not ring at audio frequencies or anywhere near them.
Dear @atmasphere please treat all my writings as a friendly argument in a search for the truth, so there is no need to apologize :)
If you have to use loading to achieve proper sound, it is a flag that
something could be amiss: Instability in the phono section, a mismatch
between arm and cartridge, that sort of thing.
I'd respectfully disagree. I'd say much depends on how the cart is designed. Electromagnetic damping due to a low R is actually quite an attractive (at least on paper) way of damping. Look at it from this perspective: linear just by the physics, no deterriortion, easy to implement and easy to control *by the user* with a great accuracy by changing R. Mechanical damping on the other hand, could be more challenging to implement with non-linerities, aging effects, no user control etc.
I don't say that achieving critical damping is doable or even desirable from the sonic perspective.
I got that from @intactaudio 's comment about sidebands. I apologize as I did conflate your comments and his. Critical damping of the cantilever is one of the very few explanations I can think of for the phenom he described.
I think here lies the answer - "depending on the cartridge". I can
imagine that for some cartridges, or better yet, some cartridge/tonearm
combinations, the extra damping from a low R, combined with other
factors may compromise the tracking. What I fail to see however is that
this should be some universal law.
Its not so much a universal law as it is something to be aware of. If you have to use loading to achieve proper sound, it is a flag that something could be amiss: Instability in the phono section, a mismatch between arm and cartridge, that sort of thing.
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.
I don't say that achieving critical damping is doable or even desirable from the sonic perspective.
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.
I think here lies the answer - "depending on the cartridge". I can imagine that for some cartridges, or better yet, some cartridge/tonearm combinations, the extra damping from a low R, combined with other factors may compromise the tracking. What I fail to see however is that this should be some universal law.
So now I am curious- at what frequencies did you make your measurements?
I did not do any measurements. I tune R_load by ear, usually preferring lower values, and have never experienced any HF mistracking.
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.
@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.
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.
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.
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.
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.
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.
"[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
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.
You must have a verified phone number and physical address in order to post in the Audiogon Forums. Please return to Audiogon.com and complete this step. If you have any questions please contact Support.
