Cartridge Loading- Low output M/C

Wyn, I am glad that JCarr finally mentioned the fact that most LOMCs I know about have a much lower nominal inductance than the 0.5mH, on which you based your first set of calculations, and thank you for re-calculating your results based on more realistic values of inductance.  I also want to thank you, Al, JCarr, Ralph, and others for this civil and erudite discussion.  Such educational interchanges are all too rare on audiophile websites.  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.  I am sure my results have most to do with the nature of my particular phono stage, my downstream components, and my two ears,

Yes, it has been quite interesting and informative for neophytes like myself.
By the way, I constructed a model for the cartridge back EMF using Lenz's law and incorporated it into my simulations.
For those who are interested, the simplest version of the law is V(t)= -LdI/dt.
In this case the parameters can be measured (the LC100A meter from Ebay is a great way to do it) and the back EMF acts to oppose the voltage developed in the coil. The fractional change (attenuation) in the signal voltage is easy to calculate as it approx. equal to -L*2*pi*frequency of interest/Rload. So, it's inversely proportional to the load R and proportional to the frequency.
For example, for a 11.8uH cartridge, with a 100 ohm load the error at 20kHz is c. 1.5%.
The model measures the current through the coil and adds a correction of the form -k*s to the source voltage.
The effect can be seen both on the frequency response and on the transient response of the Phono preamp that I'm simulating.
Is anyone interested in this, or the simulation results?

Hi Wyn,

Yes, that is of interest. And I agree with your math, of course, while having two comments:

First, I’m not sure that "back EMF" would be the best terminology to apply to what you are calculating, or the best way of considering it (see the next paragraph for my perspective on that). As you no doubt realize, that term is commonly used in the context of speakers, where a signal is applied by an external source, and back EMF is generated by the speaker as motion of a driver coil in its surrounding magnetic field continues beyond what is called for by the signal. In this case, of course, it is motion of the cartridge’s coil which generates the signal, as opposed to coil motion that occurs in response to an applied signal.

Second, I believe that what your calculation reflects is simply the high frequency rolloff which occurs as a result of the interaction of cartridge inductance and load resistance, putting aside the effects of capacitance. In your example, 2 x pi x f x L (i.e., inductive reactance) would become equal to the 100 ohm load impedance at a frequency of about 1.35 MHz, resulting in a 3 db bandwidth equal to that amount. So the error you are calculating, if indeed it can be considered to be an error, would seem to be insignificant at audible frequencies.

Regards,
-- Al

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.
In any case, yes, the error is small for the Madake, and the effect on the 1kHz square wave versus an ideal RIAA is miniscule. I'm currently running sims with varying load Rs to see what significant effects I see. My initial look suggests that 100 ohms has a faster rise time than 47K, for example- but it's early days.
By the way, higher inductance carts will need proportionally higher load Rs to achieve the same level of non-interaction.

The recording process (particularly analog) imposes restrictions in the frequency response- limiting the HF and LF responses. These restrictions are not set in any standard and are usually due to limitations in the equipment used (Tape recorder and lathe frequency responses and dynamic ranges for examples). Good recording engineers try to minimize the effects, but they still exist.

Hello Wyn, when I saw this comment, because I run a small LP mastering operation, I thought you might like to know that the bandwidth of most LP mastering systems can go pretty high (and down to about 5Hz). Our Westerex system is bandwidth limited by a filter on the mastering amplifiers at 42KHz. This is mostly done to prevent damage to the cutter head from errant signals at the input, since the RIAA preemphasis causes a wee bit of extra gain at that frequency!  As far as dynamic range is concerned, the limitation of LP dynamic range is on the playback side, not record (although many LPs are compressed, this is mostly due to the fact that if no compression is to be used, the mastering engineer will have to spend a bit more time with the project, so compression is there to save money, not because the LP format can't do it). The cutter head can easily cut grooves that no modern arm/cartridge combination could track; the mastering engineer's task is to make sure that the cutter head does not exceed those playback limits!
Just to be clear about the effects of RFI on a preamp, the designer's concern is not so much about RFI from external sources like a radio station (although that certainly is a concern) but the RFI generated by the cartridge and interconnect cable combination (and also the input capacitance of the preamp itself). If immune to the latter, it will also be immune to the former.

Thanks, that's useful information. I have a good, old, friend that's a hi-fi reviewer in the UK and also is part of the team that produces the "Chasing the Dragon" series of recordings. We have arguments about this all the time as he feels so sure that his A810 with NE5532 opamps galore in the playback path is so superior to LPs and he often cites the limitations described to him by the mastering engineers. 
I assume that the 42kHz cut off isn't a single pole- and I also assume that it uses some kind of relatively benign analog filter like a butterworth or gaussian.
I too have a tape deck- an Otari MX50 that also uses opamps galore- some better than NE5532s, some worse, that sounds, to my ears equally good but slightly different to his A810 and which measures imperceptibly different to his except infinitesimally worse W&F and lower distortion.

I have a long history of listening to tape playback- starting from the time when I was with Decca at their production plant in Malden England, and to my ears a well recorded, well mastered and pressed LP can be just as good.

Dear @lewm : Something is " wrong " ( maybe I. ) or not clear somewhere because in my system loaded at 100 ohms a LOMC cartridges ( almost any. ) quality level performance is truly fantastic and yes wide open, precise and clear at the top end frequency range. Tonal balance is superb and you never can say " sounds a little dull ". Dynamics are great too, transientes, rythm and everything.

All those’s contrary of what many of you that are loading at 47kohms posted in this thread and I know for sure no one of you are deaf but neither I.

I have to say that I’m very sensitive to both frequency extremes that’s where belongs my main self home system/room educational foundations to my main target that’s truer to the recording been live MUSIC the top reference.

I listened many many audio system/room other than mine through audio dealers and mainly in audiophile places where normally ( even with 300K+ dollars systems. ) those both frequency ranges are a little " out " from what I’m learned must be.

Yes, as always I can be wrong but some of the audiophiles at their places and after make some " changes " in their systems agreed with my take.

Of course and as I posted my system has no single problem with cliks or pops.

Many of us are accustomed or like more " high frequency "/frequency deviations ( that I normally name it:distortions. ) that I can’t listen in in live acoustic events.

Obviously that almost each one of use have diferent home system/room targets .

Anyway, very enligthing discussion.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

There is a tremendous amount of info here, both super technical as well as the basics. If you do one thing, that is click on the link JCarr posted from 4yrs ago on Whatsbestforum, it gets you well into cartridge loading topic by an expert.
I read that article 3yrs ago and that opened my eyes to LOMC loading, and what is happening from stylus thru phono stage to power amp...and why.

It is very true, we must use our ears and chose what sounds best for us, even in the Lyra instruction booklet it gives you the mathematical process but then also states, or determine by listening.

The one thing for sure is that I will never own a phono stage that only gives me a couple loading options as well as no gain settings (more gain is not the answer).
And yes I do want to enjoy the music, more than anything, but I want that at the highest level of resolution and dynamics I can afford or adjust for.

Cheers,

Well, if the simulations are to be believed the results are quite interesting, if hardly entirely unexpected.
I'm simulating an opamp based phono stage with near perfect 20-20kHz RIAA compliance, with both active FB and passive RIAA implementations. The feedback design has the extra HF pole.
 If you load the cartridge with 47k the input rings at the resonant frequency of the input network (>4MHz) when you hit the RIAA preemphasis network with a 2KHz square wave and it lasts for 10s of us. 
When the load is reduced to 1k the ringing is damped and it ends in a few us. 
Into 100 ohms the response is well damped with a small over shoot and after 1us it tracks the input perfectly. At 400 ohms there is just a small amount of ringing.
Adding 0.1uF to the 100ohm load noticeably slows the edge of the feedback RIAA preamp output square wave compared to 85pF. Increasing the R to 400 ohms, and keeping the 85pF shows the slight ringing on the output response but doesn't have a reduced rise time, increasing the R to 47k shows significant near-oscillation at the output of the preamp.
The passive design shows none of these pathologies with the change in load R, and always has a significantly slower and essentially constant, risetime, so clearly the RIAA de-emphasis producing opamps are reacting to the HF signal.
So, perhaps the answer to the loading question is, no matter how unlikely it seems- it depends on the architecture of your phono amplifer!

Great info, Wyn; thanks! And thanks also to Catcher10 for his inputs.

So, perhaps the answer to the loading question is, no matter how unlikely it seems- it depends on the architecture of your phono amplifier!

This is exactly what Ralph (Atmasphere) has said in more than a few prior threads here, as well as in this one, that optimal loading is primarily dependent on the design of the phono stage.

BTW, the Herron phono stage I own, which as I previously mentioned I (and also some other members here) run with essentially no resistive load whatsoever (just the input resistance of a FET stage, which is nearly infinite) uses passive RIAA equalization. As do the phono stages that are built into Ralph’s preamps.

Thanks again. Best regards,
-- Al

We have arguments about this all the time as he feels so sure that his A810 with NE5532 opamps galore in the playback path is so superior to LPs and he often cites the limitations described to him by the mastering engineers.
I assume that the 42kHz cut off isn’t a single pole- and I also assume that it uses some kind of relatively benign analog filter like a butterworth or gaussian.

Actually the 42KHz is just handled by a single choke in series with the cutter head!

So, perhaps the answer to the loading question is, no matter how unlikely it seems- it depends on the architecture of your phono amplifer!

+1

I’ve always preferred passive EQ as it seems to result in a more stable preamp. I’ve maintained that a lot of ticks and pops heard in many phono sections are actually the phono section misbehaving (due to oscillation) and not actually audible ticks and pops on the LP surface; your modeling *seems* to confirm that (please correct me if I am misinterpreting your data). To that end, I’ve often recommended that one look into the matter of cartridge loading; if the preamp does not seem to need the input load and is alright with the resulting (RF) peak, then a pretty important side benefit will be less ticks and pops.

In non-opamp circuits, the presence of stopping resistors at all input nodes of the active devices in the circuit seems to play a role (many Japanese phono equalizers from the 60s-80s had no stopping resistors at all; not surprisingly they seem to exhibit more ticks and pops). So I don’t think that feedback is the destabilizing factor as I know of phono equalizers that are well behaved (no need of loading, no ticks and pops) that employ feedback EQ. I too feel that topology plays a huge role!

catcher10 (and other experts here)
In absolute terms, does a Phono pre with multiple gain/loading options only sound it's absolute best at 1 permutation of settings?
I ask because I once read a ARC Ref 2 Phono review and it was said that it sounded better at the lower gain setting. Then in my pre (an older ARC Ref) the loading involves soldering resistors onto some taps. To my ears this always sounds more veiled than without the resistors with the 5 carts of different recommended loadings that I have owned.

No, you are interpreting what I say about the simulations quite right.
It definitely seems that if you want to terminate the cartridge in a high impedance- and it hardly matters whether it's 47kohm or 1Gohm, you'd better be using a passive RIAA stage, or possibly an inverting RIAA stage- I haven't checked that out yet. 
The non-inverting active RIAA can be 50-90dB worse than the passive design in the several MHz regions where the resonances and RFI reside if the extra pole is not included,  and 20-60dB if it is included. Loading the cartridge with 100 ohms gives you most of the difference back, but the passive is still c. 20dB better.
The non-inverting active, however, has superior square wave response than the passive- due to having higher frequency correct amplitude harmonic content- under low load R conditions- but who knows if that matters.
I wonder if this correlates against the reports from various reviewers concerning their preferred load impedances.
Back to the cutter- could you possibly please tell me a few more pieces of information- like the inductance you use and the C/R of the head input?

Dear @almarg and friends: This came for the very first post by Wyn:


""  the bottom line is- you’ll never get it perfect. You can either listen and decide what you like......... A couple of other things, the RIAA deemphasis of your amp comes into play, and it’s not unusual for that to be off c. 0.5dB or so over some frequency range, and most amps have restricted frequency responses to reduce the infrasonic and ultrasonic signals.
Also, your room/speaker response is probably poor with errors at least as large as any from the above sources, so unless you’ve characterized and corrected that then listening is probably your best bet. """


and then from the others posts these hiligths:

""" I'm a believer in fixing the problem where it exists and not by adding an additional parameter to an already over-constrained problem. """


"""  Unfortunately accentuated dynamics and resolution all too often mean a really nasty peak at the HF. In my experience......... testing the RIAA response can be a real eye opener.
Most of the differences in response that occur due to changes in load are in the 10k-20kHz range. """

"""  Again, listening is best, but be careful not to delude yourself.
Audiophiles (myself included) tend to get seduced by what are essentially deviations from what the real listening experience provides- such as excessive detail, ability to resolve supposed room artifacts etc. etc.
These effects, in my substantial experience of live performances, just do not exist in a live listening environment,..."""


"""   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 etched image that many "high resolution" MC cartridges produce.   """


"""  increasing the R to 47k shows significant near-oscillation at the output of the preamp.
The passive design shows none of these pathologies with the change in load R, and always has a significantly slower and essentially constant, risetime,......................................................................................................................... perhaps the answer to the loading question is, no matter how unlikely it seems- it depends on the architecture of your phono   """


Everything he posted is full of lessons for me and maybe for some other readers.

Is important for me read those highligths that gives a more " affordable " information for all and important to note his " perhaps " in last higligth.


This thread made that I remembered one time in one of my trips to USA when in an audiophile place whom owned a top system/room audio system ( 150K-200K $$$. ) I attended and when we were listening his system I noted something was wrong with the tonal balance of his LOMC cartridge .
His system in those times ( between other items ) had: Walker TT, Dali top of the line speakers, tube monobloks amps, first rate cables everywhere, very good room treatment many audiophile tweaks and a four chasis all tube phono stage ( no SUT. ).

Mi first question to him was the value of the load he was using where I ask him to lower to at least 100 ohms and he did it ( he was loading it at way higher R. ) and ligths come out " and he noted at once as I did it." 
Everything changed for the better. Over the time my experiences with my and other systems attest the same behavior ( tubes and SS electronics. ).

Al, I posted to you that the capacitance issue is almost useless when exist several other critical subjects we have to fix in our systems before that.
As Wyn posted: "  so unless you’ve characterized and corrected that then listening is probably your best bet. """ followed by:
""" 
fixing the problem where it exists and not by adding an additional parameter to an already over-constrained problem """

Analog is full of " problems " and " problems " of more vital importance that the capacitance issue and are on those " main problems " where we have to work before other " new " parameter.

If I remember years ago (but I'm not sure if he was. ) I read probably in the long MM thread a JC post telling that for capacitance could has an audible effect with LOMC cartridges the amount of capacitance must be truly high. This was the second time that I read it ( first time somewhere in the net. ) . As I said not totally sure if was JC but was in Agon. I really never bother about as I don't bother yet.

As @krelldog and @catcher10: " 
There is a tremendous amount of info here, both super technical as well as the basics """.


R.

One other thing, setting the input resistance >>100 ohms can have unfortunate effects on the input stage amp if the bandwidth is high. For example, with a AD797 opamp the gain bandwidth product is 110MHz, so for a c. 2.5MHz electrical cartridge resonance  the amp still has a gain of 44, so if the input stage has a high gain the total gain at resonance can be 35+32dB=67dB, or a gain of about 2k, so if, for example, there's a transient click which generates a 1mv rms output at resonance the input amp can produce 2v rms output.
This may not be an issue, but it would seem to me that when using a high resistive load an input amp with either a very high overload margin or a deliberately limited bandwidth (<<2.5MHz) would be essential. Once again, preamp architecture seems to be the deciding factor.

This may not be an issue, but it would seem to me that when using a high resistive load an input amp with either a very high overload margin or a deliberately limited bandwidth (<<2.5MHz) would be essential. Once again, preamp architecture seems to be the deciding factor.

It is an issue, as far as I can tell. Overload margin is really important otherwise ticks and pops abound.

When you cut a lacquer, if the stylus angle and temperature are set right, the silent groove is so quiet that the playback electronics are the noise floor. The test LP you get back from the pressing plant comes with a form that the producer has to sign- so the test LP gets a listen to insure an absence of ticks and pops. So it follows that most LPs should be nice and quiet, and in practice if the phono preamp is up on its game, they will be.
I don't have the values you requested, but the coil at the output of the cutter amps isn't very large. The inductance of the head varies depending on the voice coil used and we've used both. The older version use a series resistance, while the newer ones are higher impedance (about 10 ohms) and don't employ the resistor. I suspect this could be handled in a better way, as well, the cutter amps were designed in the late 1960s- they are pretty primitive!

Well, the preamp design that I've been referencing has an unweighted 20-20kHz S/N ratio of 66dB at 1v rms output, 0.25mv rms input. Assuming the 0.25mv output from the cartridge is at 5cm/sec, and the max velocity before miss-tracking is 20cm/sec the effective dynamic range of the preamp is 78dB, unweighted. 
I don't have any LPs which do not noticeably increase the noise floor once the stylus is dropped, but that could mean that the LP dynamic range could still be >70dB weighted. For the passive design the gain is split c. 200x for each of the two gain stages- which produces c. 50mv rms at the output of the first stage and c.1v rms at the final output due to the attenuation through the passive equalization network. 
The amplifier GBW product provides the necessary roll off to prevent overload and the output noise is imperceptibly different between the passive and active designs. The active design measures slightly better as far as harmonic distortion is concerned, but were talking about the difference between 0.001% @ 1kHz, 1v rms,versus 0.001% @ 10kHz, 1v rms as at lower frequencies noise dominates and I can't measure it with my primitive test equipment.
If I add a 42kHz cutter -3db point, then not surprisingly, the 20kHz response is down by c. 1dB.
I'm using the opamp preamp for three reasons- I can simulate it quite well, it sounds, actually, pretty good, and it's easy to make changes in topology to examine various aspects of the design to investigate various things- such as the mystery of loading.

Dear @wynpalmer4 and friends: Other that your very clear higligths I posted other gentleman posted in this thread:

"  If your set up sounds "wrong" with more modest loading, such as 100 ohms, something might be wrong elsewhere..."""

I don't know why all those " huge " inistence on the capacitance LOMC subject maybe because one of them is a seller .

Now, you are a gentleman that already use around " 100 ohms as loading the LOMC cartridge and in the Madake 60 ohms with great results.

I experienced always in the same way however a " live " evaluation tests are in order and as always I just did it because it's the best way to learn something new or confirm our believes.

I have my own fully proccess to make audio items evaluations in my system through listening sessions.  My tests evaluation was changing only one parameter that's the cartridge load impedance going from my usual 100 ohms to 47kohms and 100kohms. Fortunatelly I have that proved proccess ( tested in my system and many other diffrenet systems. ) and a truly high resolution and precise system. Well this is what I found out against 100 ohms:

I found out no more transparency or openess in the system presentation in those HF range but what I heard is lower " definition " of the fundamental and developed harmonics even in some of the tracks of that test proccess part of the detalied HF with 100 ohms not only was veiled but just disappeared. The transient and decay time changed in a way that makes everything more " ethereal " than with live music definition.
The overall presentation at 47/100k has a penalty not only in the HF range but even at the lower ranges maybe because the " contrast " in between goes smaller but I can't be sure why.

Taking those Wyn highlighs and  the larryi ( now I remember whom posted the highligth at the begin of this post. ) I agree with both of you and what larryi said is true " something wrong " in the system.

Seems to me that some of you that prefer 47K with out intention to do it what in reality are doing is " compensating " some " faults "  somewhere in the audio system links of that complex system chain and could be problems in more than one of those system links.

My take is that before we make changes on LOMC cartridge loading and especially from 100 ohms to 47K we have to be totally sure that at every single system link we have no " problems " but if you are unaware of that then you have to make a proved testing evaluation using a proccess that permit a " true " evaluation. Obviously that we can't be absolutely sure of the proccess validity but we have to be nearer to that " true ".

Is more frecuent/often that we make changes where we don't need to do it but anyway we did it and think that were for the better when in reallity are only hidden system " errors " somewhere.

Of course that for those evaluations we have to be honest with our self and not biased on purpose or because we are accustom to this or that characteristic in the sounds and obviously that we have to be sure that we know how sounds each instrument in a near field live event.

Btw, I made my tests as always: at normal seating position and at near field position. As a part of my proccess tests headphones are inside but normally I don't use it because I'm truly engaged with the system but this time I used and confirms what I said. I always prefer the near field test than the headphones because I'm not accustom to.
Btw, I tested through too using an additional full stage with my AU-1000 SUT with similar results that in the active high gain phonolinepreamp.

Now, sounds bad at 47K? no it did not but when you are accustom to the top quality level I'm the you can listen the difference at once not 3 hours latter, it's immediatly.


Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

To me I have always viewed with LOMC "100 ohms gets you a nice sound and 47K ohms gets you a very open nice sound". Then everything in between, but all this has many depending factors that are outlined in several posts @wynpalmer4 as its so true that most of the differences in sound we hear is due to the differences in phono stage design, topology. I think most if not all distortion we hear from increasing value of phono stage input R load is intermodulation created by the phono stage, not the cartridge. I think this varies also due to the circumstances, how sensitive the phono stage is to RF energy and such and don't forget about how the whole cable/wire chain affects too (cartridge wiring, tonearm wiring and phono cable to amp) maybe HF sensitivity of the phono stage.

I think it is clear, that all phono stages react differently based on topology and what the designer did, just too many variables to have the "correct setting", I think you just want a phono stage that will be stable within a given range and maybe the designer can advise if there is such a range they were thinking of.

I hate when a reviewer does not advise what settings they are using when reviewing a phono stage, because this could dictate the sound character they are hearing and whether they give a favorable review or not....I actually believe most are not listening to a phono stage that has been properly setup. Not all LOMC carts sound best at 100 ohms......Variety is the spice of life!!

Cheers

While rules of thumb often get hit with a hammer, I’ll offer two that work for me:

1. Start loading at 25 x DCR (or internal resistance, 5 ohms for the Bronze), then raise or lower (usually lower) to taste.
2. Always listen to almarg.
Best,Bill

Dear @catcher10: "  Not all LOMC carts sound best at 100 ohms......", as you said depends on phono stage but as a fact depends on the whole system/room.

Normally at 100 ohms has to sound good. Now if we want the penultimate loading for a specific cartridge this is almost imposible. 

During my tests I tested 3 cartridges and all performs in the way I posted with 47k.
As a fact and at least in my system I'm not bother any more for that " wrong " 47K loading with LOMC ones. But that's me.

R.

@rauliruegas 
Well, if you have done all the listening tests and have settled at 47K ohms within your system then carry on. At the end of the day its about what your ears tell you and quite possibly your room.

What I think most of us are saying is, depending on your phono stage will depend on what you settle on if you have adjust-ability, don't settle with 100 ohms just because it is close to 10x the internal, which is what you read over and over.

Figure out your cable capacitance and then get with your cart mfg and find out how they built the cart and what suggestions they have on loading. Start there.......then adjust till your ears are satisfied. My route was to use the mathematical process based on how Lyra designed the Delos. Sure I played with loading quite a lot, but the math version clearly gave me the highest level of resolution and dynamics.

Cheers,

Bill (Wrm57), thank you kindly :-)

Best regards,
-- Al 

Dear @catcher10: Usually my first take is to follow the manufacturer advise, at the end he is the designer and was him who voiced the cartridge but it's here precisely at the cartridge voicing where belongs the " problems " and I said problems because I don't find other word to explain it.

It's obvious that other of what math tells to the designer he makes the voicing with a very specific system/room that normally we just have not any reference/names of the audio items in his system so we all have a heavy " handycap " to " load " over our shoulders.

Each one of our systems/rooms are different too and those maths are not taking in count all the system/rooms variables as does not takes in count the more problematic of all variables that are we audiophiles, you and me with different sound/music knowledge  levels and with different system/room targets for those sound and MUSIC.

To deal with so many variables is almost impossible to fix it manipulating one parameter as the load impedance or capacitance or both of them..

Through my audio life I learned from several audiophiles, item designers and even reviewers or audio true roockies. 
If we always are willing to learn we can do it coming those " lessons " from any one and everywhere and we learn when we achieve a new knowledge or when we confirm what we already know or when we learn what not to do and why.

I'm a follower of what I learned and what I tested about and I have a " simple " rule to put my errors/omisions at minimum and is thatv through some years now I try that at each single link in my system/room chain everykind of distortions/deviations/noises/resonances, or the name you can give, stays at minimum to be truer to the recorded on those LP grooves. I know that my targets about are not easy to acomplish and I'm still working on but this " simple rule " tells me that if everything is " fine " in the system/room my taste or any one taste is not critical or really important because trhough that system/room  what you listen always will like you because staying truer to the recording you can stay not so far aways from the reference that's live music.

I'm not biased with my taste, I'm biased with the MUSIC and I know how instruments performs in near field that is how the recording microphones are at the recording sessions.
I don't have control over what's in the recordings but I can have some control through the playing overall proccess and that 47K loading for LOMC ones is out of question for me specially after tested.

I think that overall subject with we audiophiles is that the AHEE teached us to trust in what we LIKE when several times what we like is just wrong but it's what we like, we are biased that way.

I owned at least 3 VDH Colibri and in all those cartridges the manufacturer advise with out matters its output level the loading figure was 50ohms-500ohms. I listened with different loading settings inside that range and always finished at 100 ohms and I can tell you that at 500 ohms the cartridge in my system is just unlistenable , just imagine at 47K: out of question.

I think that we can't hide our ears sensitivite losting or system/room " problems " behind that 47K loading impedance.

Again, first than doing that we have to make an exhaustive check up on each link of our system/room chain and why not: that a professional makes us a ears cleaning every 3-4 months and stay away from very high SPL for more than 2-3 minutes and of course attend at least one day a week to listen live music.

No, I don't buy that 47K/capacitance issue because no one of his proponents prove me that is the way to go and because my tests confirms is a wrong road to go. At least for now. Maybe, I need to learn or not something I'm missing here or not.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

Dear @catcher10: I for got:

""" I have my own fully proccess to make audio items evaluations in my system through listening sessions. """

Through my self " designed " evaluation proccess I don’t listen to the " woods/forest " because we just can be losted inside it.

Years ago I choosed very carefully the specific LP tracks ( different LPs. ) to use in that overall proccess and at each track 1-3 minutes that gives me/shows me specific characteristics of sounds ( mainly at both frequency range extremes that’s where music belongs in a home system/room. )

Always use same tracks for the same specific characteristics. In this way the proccess is repeatable and through the time with absolute control on it. I even know exactly the tone of a click in the track when exist on it.

One of the advantages to stay away from the " woods/forest " is that first I can’t be losted second that I test at an specific branch in an specific tree insided the forest and third is that with out doubt I know for sure what to look for for the evaluation validity/certainty. There is no " land " to mistakes no matter what.


I have to say that for me was and is a very useful tool that I can use with any system/room and always determine what is happening down there.

Btw, Allaerts is another example of what I posted and @amg56 is rigth. I own the MC2 Finish Gold and J.Allaerts is extremely precise not only in the specific loading but VTF too where in both the range to move is a minimum one.
Btw, was my Allaerts cartridge the sample used to the review in Stereophile, I borrowed to MF because the manufacturer " never " has cartridges for that, is always over-sold.

R.

@rauliruegas 
Maybe I misunderstood your previous message about you loading at 47K ohms.....all is good.
And yes room acoustics and many other issues we cannot really control come into play.

I have not had my ears cleaned by a professional in many year, I don't remember the last time this happened, should look into that :)

Cheers

I am using a humble Musical Surroundings Phonomena II. My daily driver is a Hana SL mounted on a Sumiko Premier MMT with continuous wiring to the RCAs; ergo shorter or lower capacitance cable is not an easy option. The integrated is a Primare I32 and for cartridge set-up I usually use Stax SRX MK 3 headphones, so only the I32's pre-amp is in the loop.

The internal impedance of the Hana is 30 Ohms. The Phonomena has a capacitive loading switch which I set to 200 pF, the lower option. Between 475 and 100,000 ohms I must confess that the differences I think I hear in the music are so small they may be imagined. Is this to be expected or should I run immediately to a good Otolarygologist?
What I do hear is that the hiss and ticks between tracks are less at 50 and 100 kOhms.  

@2channel8 The PII is a great phono stage, with huge adjustability. Performs well above price point. I have one in another system.....
The Hana is a .5mV output, what gain are you set at? Hana suggests >400 ohms loading, what are you at and do you know the capacitance of your phono cable?
If you are running gain at more than 56-57dB...that might be why you don't notice any differences. Too much gain can kill dynamics and resolution......

Between 475 and 100,000 ohms I must confess that the differences I think I hear in the music are so small they may be imagined. Is this to be expected or should I run immediately to a good Otolarygologist?

About 30 years ago I worked on developing a box that would allow a person to know what the right loading value for a LOMC cartridge actually was. To this end, I had to pass squarewaves through the cartridge, as the proper loading would be that which prevented 'ringing' a harmonic distortion caused by the fact that the cartridge is an inductor.
To my surprise, I discovered that any LOMC could pass a 20KHz squarewave regardless of loading. The only thing that changed was if the loading value was reduced too much, the output went down.
That was when I realized something else was afoot with loading. Its not the cartridge, its the preamp that is reacting, as described elsewhere in this thread (the loading box concept was thus abandoned).

Some takeaways (all previously covered):
1) If your phono section requires loading to sound right, it is due to an overload margin problem, inherent instability of the circuit, or both.
2) If the circuit is unstable, you will experience more ticks and pops that sound like the LP has a noisy surface.
3) the loading will decrease the compliance of the cartridge, which in turn will reduce its high frequency response. How much is hard to say, but some people (myself included) have heard loading act like a tone control, and this may be part of the reason why, since under normal circumstances, the RF peak that results is usually well outside the audio band unless a MM cartridge is used or the tone arm cable has crazy high capacitance. 

"""   (all previously covered) """

So we have here an " instant  repetition " of those take aways that at the end are really usless because every one already owns what they own.

Maybe, another " instant repetition " is in order for really slower brains ( stupid. ). Go a head.

@cather10 Thanks for the encouragement. I like the PII very much and think I will live with it at least until I upgrade my tonearm. I had been running the Hana at 475 Ohms and 56 dB until I read this thread this morning. Then I put on the cans and did some listening and am going to try 100K Ohms for a while and see what it's like to live with that. Now here's where I show my lack of expertise. I haven't been able to measure my phono cable's capacitance. My multimeter just reads 0.0 F, even though it has a uF range. Neither have I been able to track down the capacitance per foot of the Cardas 4x24 connecting the arm to the PII. 

@atmasphere , I am not sure of the implications of your statements as they regard my set-up, unless it's that the PII has a stable circuit. I hope.
Thanks for all the sharing!  

^^ Sounds like it to me :)

@2channel8 well if you have been running at 475 ohms then I can only assume you have a low cap cable. If you had a high cap cable I have a feeling you would hear the difference.
You should find out though, email the cable mfg and ask them. Let us know what 100K ohms does for you.....I have never tried that high of a setting on my Nova II

Well, IC designers would generally consider an amplifier circuit that has a section with a 35dB resonance to be pathological- that is, basically a problem waiting to happen- unless, of course, the goal really is to produce an oscillator, or at least a marginally stable system. All it takes is a small amount of unwanted feedback due to parasitics - resistance in the ground, inductive coupling or capacitive- anything could do it- from a point where there’s enough gain and phase shift back to the resonance and all sorts of nasty things can happen. So, even though we can model all of these effects to a degree that the non-practitioner would consider to be near magical (yes, we can do EM simulations for complete circuits that are much more complex than an opamp, and capacitive/parasitic resistance runs are entirely routine) we generally choose, just for good practice, to eliminate any such effects as a matter of priority. Just try getting something like that through a design review.
Seemingly, the practice in audio design is somewhat different.

In this thread phono cable capacitance has been mentioned as a factor to consider when determining the the MC cartridge loading. 
This is from the Morrow Audio website:

"Magnetic cartridges are the only cartridges that might be affected by cable capacitance. With moving coil cartridges, cable capacitance is not a concern."

Is the above a true statement?

I am using their PH4 phono cable, the capacitance is 392pf per meter. 
Turntable is a SL-1200G > Hana SL > PS Audio GCPH with Underwood Mods.     

"Magnetic cartridges are the only cartridges that might be affected by cable capacitance. With moving coil cartridges, cable capacitance is not a concern."

Is the above a true statement?

No. It is advantageous to keep the resonant frequency as high as possible.

Dear @catcher10 @2channel8: That Phonomena phono stage seems to me that is something special and especially that so low price. I never heard of it before but maybe is time to evaluate it. The owners and reviewers speaks excellent " things " about the item.

This is a highligth from an owner in reference to his cartridge loading:

"""  Ortofon Cadenza Blue (MC). I am using a Pro-Ject Audio 2Xperience SB turntable and Ortofon 6NX interconnects. The Phonomena also allows me plenty of flexibility in choosing gain and impedance loading. With the Cadenza Blue I am using a gain of 56 dB and an impedance of 59 ohms (I like the tight, defined bottom end). """

The Nova is even better, at least is what I read it. Very useful information for take care about.


R.

To get started with LOMCs I first bought a Schiit Mani, then upgraded to an Emotiva XPS-1 and now the Phonomena, so that is the extent of my experience with MC phono stages. I will say that in my opinion the MM section of my Nakamichi Receiver 2 beats them all with a Shure V15 RS.
An update on cable/phono stage capacitance: Musical Surroundings has a similar statement that MCs are not sensitive to capacitance in their owner's manual. To be sure, I have the dip switch set to the lowest setting. I've sent an inquiry to Cardas, so we'll se what they say, if anything. With a previous tonearm I used WireWorld Luna 7s. When I asked WW about the capacitance of the cable they said that they don't focus on capacitance; but engineer for the lowest inductance. I'm not sure if one can have a low inductance without a low capacitance. I'm just relating the story. The cables sound good.

2channel8 & Ericsch, it is true that the sonics of LOMCs themselves are essentially insensitive to reasonable amounts of load capacitance. However, note the statement by Lyra cartridge designer Jonathan Carr that I quoted early in this thread:

I should now debunk another myth regarding loading, which is that low-impedance MC cartridges are insensitive to capacitive loading. OK, the MC cartridges themselves aren’t particularly sensitive to capacitance, but the inductance of the cartridge coils will resonate with the distributed capacitance of the coils and the capacitance of the tonearm cable to create a high-frequency spike, and this spike certainly is sensitive to capacitance. In general, the less the capacitance the better. Having more capacitance (across the plus and minus cartridge outputs) will increase the magnitude of the high-frequency spike and lower its frequency, neither of which is good news for phono stage stability or phase response.

Generally speaking, the greater the capacitance across the plus and minus cartridge outputs, the heavier the resistive loading needs to be to control the resulting high-frequency spike. Conversely, less capacitance allows the resistive load on the cartridge to be reduced, which will benefit dynamic range, resolution and transient impact.

Also see the link Jonathan ("JCarr" at Audiogon) provided in his post in this thread dated 5-28-2018:

http://www.whatsbestforum.com/showthread.php?15077-Cartridge-Loading-A-Misnomer&p=258578&vie...

That is why Ralph (Atmasphere) stated above that "it is advantageous to keep the resonant frequency as high as possible."  It's all about the phono stage.

Regards,
-- Al

2channel8   6-1-2018
I haven't been able to measure my phono cable's capacitance. My multimeter just reads 0.0 F, even though it has a uF range. 

As a rough ballpark approximation, a typical phono cable may have a capacitance in the vicinity or 25 pF (picoFarads) per foot or so, corresponding to 125 pf for a five foot length.

125 pF is 0.000125 uF (microFarads), and 0.000000000125 F (Farads), so it would be understandable that your meter indicates 0.0 F.

Regards,
-- Al 

Specifically to phono cable from TT RCA box to phono stage.....Cable capacitance does matter with regard to LOMC cartridges. Lyra specifically suggests using a low cap cable, they do not recommend high cap cables. 
I also used a Morrow Audio PH6 Grand Reference phono cable for some time and when I finally asked Mike he said 390pF/mt and I was shocked! He said he never heard HF rolloff with his cables, I tend to agree but then I assume it is because you have to load at a lower setting, which is not good for the cantilever, you run the chance of stiffening the cantilever.

Once I switched to AQ Cougar at 40pF/mt and loaded my Delos to 475 ohms.That's when the higher dynamics and resolution came into play, it was a jaw dropping moment. The Delos performance rose many levels, really everything just got better.

On my Musical Surroundings Nova II I have the setting at 100pF (the new model settings are 100/200pF, the older were 200/300pF), Michael Yee changed it. In general I too hear no difference but have it set to lowest closest to my cable rating.

I tell everyone just find out all the specs you can, then go from there. You can't make the proper settings till you know all the info along the signal path. 

Cheers

Al, Thanks for bringing up the question of metering. I do own a Sencore LC meter that can measure down to the pF level. If I want to measure the capacitance of a cable, do I just place the Sencore probes on the hot and ground of the cable, with the other ends (hot and ground) unterminated? That seems right, but I am not sure.

I also think this might be a good place to summarize the points made by Ralph, Al, Wyn, etc.  First, no one is saying that there is only one correct load for a typical LOMC cartridge with very low internal resistance.  Second, I think Wyn has conceded that his first model for the behavior of such a cartridge when driving a phono stage was based on some usually false assumptions: (1) that such cartridges have coil inductance as high as 0.5mH, and (2) active RIAA correction in the phono circuit, which is atypical of most of the “best” phono stages capable of working well with such cartridges without a SUT.  Assuming inductance in the low micro Henry range and passive RIAA, we should keep associated capacitance as low as possible.  Under all these conditions, it is not inconceivable that a high resistive load, e.g., 47K ohms, might sound better than the more typical values of load resistance used by us audiophiles, e.g., 100R.  In my case, I can say that the difference between 100R load an 47K is not huge by any means, but once I had tried 47K for at least 2 or 3 of my LOMC cartridges, I’ve developed a preference for it.  What I hear is as predicted, highs seem more open and extended.

@catcher10, Why 475 Ohms? Why not 1000?
BTW, I have no report on 100K yet. Too much new digital music to listen to at the moment. 

Dear @catcher10: """  I tend to agree but then I assume it is because you have to load at a lower setting, which is not good for the cantilever, you run the chance of stiffening the cantilever. """

that was in reference to those Morrow cables. Now, I understand what that loading electrical can or could has some effect on the cartridge compliance and you said that exist a chance to.....

I think that to really stiffening the cantilever something really extraordinary has to happens.

How did you measure and what found out when changing from 500 ohms to 100omhs loading about that cantuilever stiffness that puts it on risk and how can we know when that could happens. Which the loading window limits to play inside in safe way. If any.? which is the role of the cartridge suspension dampers in all this load subject. How can be affected?

I ask that because not only my personal experiences in my system for years but what other audiophiles in their systems experienced when I was at their places. Different systems with different LOMC cartridges. They never reported anywhere a cantilever problem with their cartridges because a 100ohms load not me either.

How can I be aware of it?

Your anwers truly appreciated. Thank's in advance.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

cantilever problem/tracking habilities.

@2channel8 I use 475 ohms because of the cable cap rating and the suggested range by Lyra. Lyra suggests for a 50pF total capacitance loading range should be 510-270 ohms and for 100pF total capacitance range should be 390-200 ohms. My cable is 1.5m and total cap is 60pF, add a small amount for tonearm wiring so I reduced my starting number some. Upon listening sessions anything above 475 ohms seemed too open and bass was restricted, and by open we mean too much high end, not sound stage. Staging actually shrunk some.....
Yesterday I changed my loading to 100K ohms, just to see and listened to about 4 records. It sounded just fine but......I lost resolution and dynamics, as well as sound stage. Any surface noise seemed to be the same. It was like listening with my high cap cable loaded at 121 ohms, so 475 ohms is much closer to being correct from Lyra's mathematical suggestion. This is why my feeling is a phono stage with variable loading is key if you want the best sound possible. I have never tried 1000 ohms, it seems out of the range that Lyra suggests.

@rauliruegas I don't have test bench gear to make any measurements, if that is what you are asking for then I have to bow out, I can't tell you any specific measurements I am getting in my setup when loaded at 121 ohms, 475 ohms or 100K ohms.
JCarr also suggested that can happen if you load the phono stage too low, making the cartridge work harder. It's why he says the use of a lower cap cable allows you to load the phono stage higher resistance values.

If your cantilever does not move freely, I believe it will not ride in the groove easily, it will not read both walls easily and this is when you lose/reduce resolution and also staging draws in.
I only say this because my listening experience tells me this, in my case a 475 ohms loading gives me the highest resolution, dynamics and soundstaging possible as compared to 100-121 ohms and just recently 100K ohms. For my setup, cable, cartridge, tonearm 475 ohms is the optimal setting. Most of this due to how Lyra builds their cartridges, so for me it makes sense. This is why you need to try different settings and listen, but you should understand what is going on at 100 ohms vs 1000 ohms vs 100K ohms.

Cheers

Hanna only states a lower limit of 400 Ohms and Denon a lower limit of 100 Ohms for the DL-301 mkII. No upper limits given. Yesterday I listened to Garcia's Run for the Roses, I have a white label copy that I haven't played much so it's in great shape. I compared 2000 Ohms to 100 kOms. The bass actually sounded more profound with more of the pluck featured at 100k. But that's just one LP so far.

Dear @catcher10: Yesterday I made in deep tests again along the cantilever stiffnees issue.

Wyn posted in this cantilever regards: """ 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. """


"""
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 etched image that many "high resolution" MC cartridges produce.
From my tests I agree with him. If other gentlemans insist about that cantilever stiffness then could be just negligible and with no real significance. Cartridge tracking habilities are manteined regarding how we are loading it. """

That leaves all to PS units dependent and Wyn said: " perhaps ".

After the yesterday overall tests the behavior of my system/room confirms what I posted before: higher resolution/dynamics, etc, etc. at 100 ohms, way better than the 47k.

Btw, I loaded the Kleos at 100 ohms with true top quality performance and before that the Titan, Helikon or Evolve.


""" 
This is why you need to try different settings and listen, but you should understand what is going on at 100 ohms vs 1000 ohms vs 100K  """

the key word in your statement is: " understand ". Remember one of latest posts where I said and explain why we need to have a " bullet proof evaluation/test proccess? and forrest vs tree's branch?

I can tell you that I understand it and I hope every one can understand it too because it's really easy to be losted in the " forest " or in that often audiophile " mistake " : " I like it " .

Thank's for your answer.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

@rauliruegas I have zero issue with your post and hearing results. My point is try all settings you can and decide on what sounds best to you. All phono stages and cartridges perform differently, I am sure there are tons of people using Lyra carts that load at 100 ohms.....And if that works for them I cannot disagree.

My system does not sound like yours and my ears do not hear like yours.........
All good.....Cheers