Dear friends : For some of you that read for the first time the Wyn posts here next I paste what he posted several years ago in other cartridge loading thread:
"" No, I did not design the AD797. That was Scott Wurcer- a colleague at ADI and, incidentally, for whatever it’s worth, also an ADI design fellow. However, I know the design quite well.
He and I were colleagues in the opamp group in the 80s. He focused on high performance relatively low frequency opamps such as the AD712 and then the AD797, amongst others.
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. ""
and here somerthing that he forgot to mention and that comes in that " old " thread that shows that that " myth " of tracking problems due to cartridge loading changes is a lie and nothing more:
""" 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. """
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Dear @wynpalmer4 : Thank's to came to post here because y pasted what you posted several years ago in the subject that the " stifness in cantrilever " could have effects on HF tracking in the cartridge due to loading.
Here imhifiman and me made direct tests in our own systems with the same cartridges and after made changes in cartridge loading we detected no single difference exactly as you posted years ago about your Madake.
By coincidence and after all your evidence after all those years the same person, as in this thread, followed posting what he can't prove in any way.
Regards and enjoy the MUSIC NOT DISTORTIONS,
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atmasp, thank's but no.
Holmz, now I seen the ? in your statement. So, you are guessing again due that you do not make the tests yet. Nothing wrong with that because it's the way you are, like to " guess " as in your tonearm thread.
I hope that the test LP you bougth will receive soon. The tests on tracking and resonances will stop your " guessing ". Again, nothing wrong with that.
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@holmz : Sorry my ignorance. Could you explain in specific what do you mean with:
" the RIAA sort of works in our favour as the stylus does not have to move as far with the curve.."
Thank's in advance,
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Dear @imhififan : Thank's again for your advise. The answer to the main subjects in this and other threads ( elsewhere ) where just in front of me and never seen it,. Go figure ! Nothing like those first hand tests
Good ! !
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Dear @imhififan : " Although theoretically loading..... and 100Ω loading made the cartridge work 470 times harder than 47kΩ loading. ..............., I think the effect on the cantilever stiffness is insignificant. Therefore the test result show no difference. "
Rigth and was proved in other thread:
" 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 . 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. "
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@holmz : As @imhififan I did my tests in specific for resonance and tracking against load changes. Btw, thank's for your answer .
Differences in sound with load changes depends of the active high gain phono stage characteristics and your brain perception about. LOMC cartridges are " non " sensitive to load impedance changes.
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Dear @holmz : Did you follow the @imhififan advise? , this is his advise:
" Perform a simple test with Hi-Fi News test record will give us the answer.."
Tests for resonance and tracking changing load impedance.
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Dear @imhififan : Due that was your advise: " Perform a simple test with Hi-Fi News test record will give us the answer.."
Did you the resonance and tracking tests?
Thank's in advance.
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@holmz : That's a highligth of the Swiss CH 95K+ phono stage.
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@holmz : " I happy you have a wizard,...."
Again, you readed it in a wrong way because you or me can't find out any " wizard " in my whole system.
What's happening with you and with what you read here and every where?
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Dear @imhififan : I followed your advise and my curiosity and made some tests with 4 different cartridges mounted in two identical tonearms in the same whole room/system. Cartridges were: Denon 103, Sumiko Talisman ( B ), vdH Colibri and Ortofon A95 and I used 3 different of my test recording LPs where I runned for resonance and tracking . All cartridge/tonearm alignment set up as accurate as I can and take care of recording/stylus tip clean. I used too the after market AT vacuum hold down item as Discwasher gun demagnetizer. I did it with and with out using the damping silicon tray in the tonearms:
results in all cases were with out differences because thwe load impedance changes.
I used too 5-6 LP demanding tracks of nor mal MUSIC recordings one a Sheffield direct to two track recording where by a fault in my sample ( I think is a fault but not totally sure. ) in one track several of cartridges have a mistraking in that high frequency grooves. Here the mistracking in the 103 was what normally is no matters of load impedance and the others where the mistracking is really near to non-perceptible stays that way.
Other track was the last third part of the Telarc 1812 where not only has a toruose low bass grooves for any cartridge but at the same time tortuose high frequency with the Carrillon/tambourin/triangle. Here the load changes shows no difference on tracking/resonance and in all the LPs " clicks/pops " were non-existents due to load changes.
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@holmz : " So we are on two different targets..."
Again, for whatever reasons you just don't read in the rigth way the posts in thios and other threads because I was not who posted:
"" Your target for mechanical resonance is between 7-12Hz. The mechanical resonance is a product of the mass of the cartridge in the arm vs the compliance of the cantilever of the cartridge. Changing the load from 47K to 100 Ohms can easily get you outside of this target window- and that can cause tracking problems.. " "
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Dear @fundsgon @holmz : " also been an exercise in personal credibility..." , Really? because again your " trusti man " is way wrong, not the calculator that’s similar to the one in VE.
The Lyra Kleos is a great match for the SME V as I posted with a true resonance frequency at 9hz. Better than that impossible.
The other calculation is wrong because the Lyra compliance spec is at 100hz not at 10hz that’s what all calculators run. Japanese cartridge compliance specs normally comes measured at 100hz instead 10hz and at 10hz the Kleos has a compliance around 17-18cu not 12cu.
Any rookie knows that, even me. Obviously both of you have to follow learning, as today.
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Do it with this example:
tonearms SME 5 Cartridge: Lyra Kleos resonance frequency: 9hz.
So you can go from 47k to 100 oms and 70 pf of capacitance
Now, show that that load change puts out of the ideal range. Easy for you, just show it.
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atmasphere @holmz : " " Your target for mechanical resonance is between 7-12Hz. The mechanical resonance is a product of the mass of the cartridge in the arm vs the compliance of the cantilever of the cartridge. Changing the load from 47K to 100 Ohms can easily get you outside of this target window- and that can cause tracking problems.. " "
Where out side in specific: 5hz? 15hz? 6hz? . All you have to do is show it.
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@atmasphere :You can choose the cartridge with the electrical characteristics you want and the tonearm you like with a premise: that the resonance frequency in between be: 9hz-10hz. Then tell us from which loading impedance you have to go to stay out of the ideal range of: 7hz to 12hz.
Again, don't try to distract in any way and go straigth about. Show what only you know. Easy question.
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@cleeds : " I'm not here to win an argument or provide scientific proof.."
Obviously you can't win and certainly you can't provide scientific proof either due that " I've yet to find any fault with..."
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Where ? and don’t try to distract with other kind of information or other question: JUST SHOWS THOSE NUMBERS AND LOMC CARTRIDGE MODELS WITH TONEARMS where appears that its resonance frequency is 9hz-10hz and when you change the loading " can easily get you outside of this target window ( ideal resonance frequency range. ) " of 7hz-12hz.
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Dear @imhififan : Rigth now you can look the Telarc test LPs ( Omnidisc. ) and the Ortofon in ebay. The one Ortofon to go is that where you read: !" direct cut ".
Other nice characteristic of both is that comes with live recorded MUSIC and this sole fact makes both desirable items.
Other LP that we can use not only for tests but to enjoy music are the Opus label series.
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J.Carr: " Regarding loading of low-impedance MC cartridges, in general I recommend trying to reduce any capacitances present between cartridge and phono stage input to as little as possible. Use the lowest-capacitance phono cable that seems decent, turn off any additional capacitance in the input stage of the phono amplifier etc.
The reduced capacitance should make it possible for you use a wider range of loading impedances without having the sound go bright, peaky or thin-bodied. Conversely, any excess capacitance between cartridge and phono stage input will almost certainly force you into choosing lower loading impedances to save your ears. "
Why JC? because he is a true expert in any cartridge design and a co-designer of one of one of the great ( all time ) active high gain phono stages.
With out diminish here any one he has a way higher whole knowledge levels on the thread issues that any one of us. He is the " SOURCE " of true.
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These only 2 of your examples about that 47k input impedance:
SP6
50K ohms, all inputs. (Magnetic phono may have any value from 10 ohms to 100K ohms substituted. Also has provision to add input capacitance for matching certain magnetic cartridges.)
PV12
- Frequency Response: 2Hz to 100kHz
- Distortion: 0.25%
- Gain: 49dB (mm), 16.5dB (line)
- Input Sensitivity:
- Signal to Noise Ratio: 78dB (mm)
" In the PV12 with phono stage, this input provides the amplification and equalization required by moving magnet and high output moving coil cartridges. " This information came by CJ directly, not mine.
One of them not even handled LOMC cartridges that’s the real issue.
Useless that you insist about. No one active high gain phono stage came or comes by default with fixed 47k input impedance, no one. I posted here around 8-9 today phono stages ranging in price from 3K to 95K that’s is not only enough evidence but a true evidence and not as your CJ or SP6 and the like.
In the other side you did not gave us the answer to what you posted before:
" can easily get you outside of this target window ( ideal resonance frequency range. ) "
where are those cartridges that with today decent medium mass tonearms shows what you said coming from 100 ohms to 47k or the other way around. We need to see/read those numbers out of the ideal frequency range due to loading. Where ? and don’t try to distract with other kind of information or other question: JUST SHOWS THOSE NUMBERS AND LOMC CARTRIDGE MODELS WITH TONEARMS.
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Dear friends @holmz : Here and in other threads I told you that you read but sometimes you did not because those equations ( not all the development but help you. ) are twice posted in this thread.
Look something interesting:
" 1-
To claim that the loading affects the measurable frequency response of the cartridge is bogus. However, if inappropriate loading bathes the phono stage in copius amounts of high-frequency noise, it may start to distort (unless the designer implemented various techniques to make sure that this won’t happen), and the result will likely be intermodulation distortion. IMD products can go low enough to fall within the audible band (even when the stimuli are ultrasonic), and IMD nearly always is not harmonically related to the signal, making it particularly grating to the ear. ""
That came from J.Carr and next what was posted by other expert gentleman around EMF and tracking that involves IM too:
" 2-
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 . 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. "
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Dear @cleeds : " I've yet to find any fault..." , good because all statements are only " anecdotes " or imagination that proves nothing.
Take a look:
" The industry spec is 47K for all cartridges. " where is the " official " announcement about, say by the AES that coul confirm it? where?
" less able to trace high frequencies. " again: where are the white papers that can confirm it.
holmz asked:
" Wouldn’t loading it down to 250 ohms from say 47k make it softer as the back EMF os gone that “would have been” stalling the motor? "
his answer was: " EMF?. No...." the same answer on other 2 subject treads different forums where was proved that it's EMF:
"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. "
and in this thread you can find out the equations used. In this and the other threads your " man " "just " dead silence " against that EMF analysis the engeenering did it, not a single comment.
This is the 4 time he posted this " tale " or in the best sense a non proved anectdote:
" He ( J,Carr ) and I met and spoke about this topic at a Munich audio show 6 years ago; " so WHAT??????
" I have maintained is that the additional stiffness may decrease the ability of the cartridge to trace high frequencies, "" again, where are the white papers that shows and proves that that is happening? where?
Then he posted other tale: " the Grado Gold MI bad tracker anecdote " that proves nothing.
" Empirically speaking its easy to deduce that the load is affecting the ability of the stylus to trace the groove, which is why we see distortion as essentially the stylus is mistracking. " again: where are white papers that shows exactly that and not mere " imagination "?
" Your target for mechanical resonance is between 7-12Hz. The mechanical resonance is a product of the mass of the cartridge in the arm vs the compliance of the cantilever of the cartridge. Changing the load from 47K to 100 Ohms can easily get you outside of this target window- and that can cause tracking problems.. "
That is ridiculous and with no facts or diagrams/equations that shows exactly that. I That " can easily get you outside of this target window ( ideal resonance frequency range. ) " is not proved here or in any other subject threads. Again: only IMAGINATION.
Another " anecdote "/tale that rpoves nothinG:
" won't overload the input of the phono and you'll get less ticks and pops. I had this graphically demonstrated to me when an employee complained of a noisy LP he had bought. His LP played fine on the shop system so he brought in his preamp and there were the ticks and pops, sounding for all the world as if they were on the LP surface. "
So, " I've yet to find any fault.." ? wow ! ! I had the impresion that you was or have higher audio knowledge levels. Well all we learn something every day.
At " least " J.Carr shows his white papers diagrams that are self explained.
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I don’t care of you about, useless and futile. My last posts to imhifi.. makes no reference to you .
Bye, bye ! !
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@imhififan @fundsgon friends: As I said not only the Shure or Telarc test records are really good but other as Ortofon are great as the CBS Laboratories series and the Stereo Review and we have not forget the B/K and Vanguard.
I own in mint condition/almost new around 15-20 vintage test record.
The Ortofon are special because there is no analog recorder in the recording process due that are D2D and the Telarc neither because is a digital recording test LPs. We can find out almost any test we can make not only tracking or resonance issues.
I bougth all through ebay and the overall recording proccess of any of those old test LPs even for today " standards " are second to none.
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Dear @imhififan : We can run several kinds of tests but the real, important and critical issue for any audiophile ( not a fully technical oriented person. ) is if load impedance in a LOMC cartridge changes its frequency response and J.Carr proved it does not and this fact is what we need to know:
- Kleos electrical model (9uH, 5.4ohm, 8pF)
- Lyra Phono Pipe Very Low Capacitance tonearm-to-phonostage cable 120cm actual measurements (0.75uH, 0.325ohm, 32pF)
What these tell me (among other things) is that, all else being equal, changing just the interconnecting cable (each of which has a different capacitance characteristic), changes the optimal resistive load; and if you can afford to bring up that peak in the MHz to something <10dB then you can bring up resistive loading to about 500-1K ohms even with a highly-capacitive cable; and finally, you are not really affecting the audible high frequencies with any resistive load shown. "
He followed:
" To claim that the loading affects the measurable frequency response of the cartridge is bogus. However, if inappropriate loading bathes the phono stage in copius amounts of high-frequency noise, it may start to distort (unless the designer implemented various techniques to make sure that this won’t happen), and the result will likely be intermodulation distortion. IMD products can go low enough to fall within the audible band (even when the stimuli are ultrasonic), and IMD nearly always is not harmonically related to the signal, making it particularly grating to the ear. ""
All those was confirmed in the same old thread by an expert engineering of Analog Devices Co. when he stated with 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. 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 . 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. "
The other issue is if 47k is the standard load for a LOMC cartridge and the evidence showed in " all " active high gain phono stages proved that 47k is not the standard load impedance for LOMC cartridges and along those evidence/facts are the coments of the manufacturers/designers of those phono stages as J.Curl , M.Huber, J.Carr and others. As a fact if exist an standard load for LOMC cartridges this is not 47k but 100 ohms ( some say between 100 ohms-500 ohms. ) but as designers/reviewers/audiophiles know and say the LOMC loading is up to each audio system and owner MUSIC priorities.
Those both issues are already quite clear.
Now, if you want to " see " if load could change cartridge tracking abilities then use the Shure ERA V test record. I understand that you own an active high gain phono stage, this means with no SUT. There are other cartridge tracking test records as Telarc that’s very good. To make this kind of test through a test record you must be sure that the cartridge/tonearm overall alignment/set up is accurated and that the test record and the stylus tip are clean and optimal condition and the run the test and make the load changes you want it.
For me everything is already clear: load impedance does not affects cartridge frequency response and 47k is not the standard for LOMC loading. The test could be only for " fun ". Just do it.
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@fundsgon :
I think that all forum participants has a responsability and is not spread false information with no real evidence. That responsability comes by the fact that Agoners forums have different knowledge levels gentlemans and everyday comes rookies looking for advise looking for help so the higher knowledge level participants in the forums have all a higher responsability about that's exactly that: give help and good proved advises.
Don't you think?
That " man " as other always " cry " with the forum moderators. They have no other " exit ".
In any forum and everytime I read that spreading lie I will post about. It's each one responsability and please don't tell me that call something " black " that's " white " because this is a lie and I'm not a lier.
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@imhififan : I think that all forum participants has a responsability and is not spread false information with no real evidence. That responsability comes by the fact that Agoners forums have different knowledge levels gentlemans and everyday comes rookies looking for advise looking for help so the higher knowledge level participants in the forums have all a higher responsability about that's exactly that: give help and good proved advises.
Don't you think?
That " man " as other always " cry " with the forum moderators. They have no other " exit ".
In any forum and everytime I read that spreading lie I will post about. It's each one responsability and please don't tell me that call something " black " that's " white " because this is a lie and I'm not a lier.
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Dear @fundsgon : Maybe the " grado gold " be really good in other regards but certainly not in this one.
Now give me a help for this @cleeds too: there is a man that in the last 5-6 years was spreading false information about the same issue and it's not only false but a lie. The spreading information was and is not only in Agon but on other internet audio forums. Spread the information with no real foundation and as here I gave and give examples that said almost all phono stage active high gain phono stages are designed with way different characteristic about.
JC3 phono stage designed but famous J.Curl and reviewed by MF:
"the loading for moving-coil cartridges is limited to 100 ohms or 47k ohms, with 47k ohms also for the moving-magnet input. Curl believes that the vast majority of MC cartridges are suited for 100 ohm loading, and I concur. If you don't like that, leave it wide open at 47k, which I believe is almost never correct. "
CH Swiss 4 chasis phono stage ( around 95K dollars ). It comes with what CH named the Wizard. Please read:
"
In illustration using a very low output cartridge vs a very high output cartridge connected to the Current Input vs Voltage Input on the P1
My Sonic Lab Ultra Eminent BC: 0.6Ω output 0.29mV
Voltage Input: At 0.29 mV, the Wizard determined the optimal gain level at +70 dB of gain. This setting has audible hiss coming from the speakers at 30% volume without any record playing. On careful listening, the gain level was sufficient. Optimal loading was determined to be 180Ω by the Wizard.
Current Input: At 0.6 Ω, the Wizard determined the optimal gain level to be I/V + 20 dB, but based on listening test I preferred a much lower setting of I/V + 5 dB.
According to Ohm's Law where I = V/R, Current = 0.29 / 0.6 = 483 Micro Amps, a very sufficient level of gain based on the low impedance of the cartridge.
Clearaudio Goldfinger Statement (GFS): 50Ω output 0.9mV
Voltage Input: At 0.9mV, the Wizard determined the optimal gain level to be 70dB of gain on the Voltage input. On listening test, I preferred +60 dB of gain, a much lower setting. Optimal loading was determined to be 330Ω by the Wizard.
Current Input: At 50Ω, the cartridge required IV+ 20 dB of gain.
According to Ohm's Law where I = V/R, Current = 0.9/50 = 18 micro amps, the GFS's high input impedance resulted in a very low level of gain regardless of the Goldfinger's output of 0.9mV, which is relatively high for an MC cartridge.
The P1 "Wizard"
As with all voltage amplification circuits, proper impedance loading is crucial to the resultant frequency response of the audio signal. The P1 provides a selection of five hundred resistance values from 20Ω all the way to 100kΩ in logarithmic increments; you'll have steps of 1 ohm in the 20 Ohms range and the gaps between the values are increasing as you go upwards. The steps around 24k Ohms or above, are at 500 ohm increments. While most manufacturers will tell you to "go with your ear" while choosing the right loading, CH has developed an approach based on scientific measurements. The P1 is built in with an ingenious two part "Wizard" which will determine the optimal settings for GAIN and MC loading resistance automatically.
The P1 comes with a test LP designed to work with the P1's internal distortion analyzer.
How reliable is the Wizard? I compared the results generated by the P1 versus the results from my own proprietary test LP and analog setup software currently under development. We arrived at the exact loading choice with a difference of only 10-20 ohms. Assuming we are relying on each other as the reliable benchmark, the results are close enough to be called scientifically verifiable! "
Swiss made too and expensive Dartzeel 18NS. MC load impedance up to 300ohms:
The phonolinepreamp in my room/system comes by default with 100 ohms. Levinson, Krell and the like have the same kind of load impedance characteristic.
We audiophiles have a lot of evidence about the LOMC cartridge loading.
So, all those very well regarded designers are wrong?
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Dear @fundsgon : So you agree that 47k is standard for LOMC since appeared as is in the MM/MI cartridges ?
If yes then please re-read my last post. For whatever reasons that's what happens. I'm speaking of phono stages mnufacturers not LOMC manufacturers.
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"
When LOMC cartridges appeared at the same time the LOMC manufacturers designed/manufacture too SUT because there was not active high gain phono stages. So, all phono stages came with 47k where the SUT must be connected.
Latter on appeared the active high gain phono stages to drive LOMC in exclusive way with no facilities to handle MM/MI cartridges, even those LOMC phono stages cames ( even some today ) with impedance load different values choices coming from 100 ohms to 1k ( more or less. ) where no one came with the option to choose 47k. "
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Dear friends and @judsauce : " You provided frequency response as a function of loading. "
Well , those charts that I posted ( and I deleted latter. ) was the main part of the J.Carr white papers and the foundation for his statement:
" To claim that the loading affects the measurable frequency response of the cartridge is bogus. "
With LOMC cartridges the changes in the sound " color " that happens when we change impedance loading comes and is developed by the phono stage it self not by the LOMC cartridge . As I said any one of us can change the loading impedance according what we like or is near our targets on each one room/system.
Hagermann made a calculator to know the frequency resonance of the cartridge coming from the MM cartridges and in his white papers when he speaks of LOMC cartridges he said: " that’s why normally 100 ohms is the manufacturer advise " ( something like that. ).
In the other side the main issue for we audiophiles is if impedance loading in a LOMC cartridge affects frequency cartridge response and the answer is: NO, it does not affects the cartridge frequency response.
The " golden boy " said everywhere/all audio forums to load LOMC cartridges at 47k and in one thread he posted that’s because is the standard value not in specific to MM/MI cartridges but for LOMC too ! ! ? ? ? Go figure !
In that thread an audiophile posted " 47K is the standard for MM. Not for MC. " and the " golden boy " gave and posted this answer:
" Actually 47K is the standard input impedance for all ....., MM or LOMC. "
Obviously is wrong.
When LOMC cartridges appeared at the same time the LOMC manufacturers designed/manufacture too SUT because there was not active high gain phono stages. So, all phono stages came with 47k where the SUT must be connected.
Latter on appeared the active high gain phono stages to drive LOMC in exclusive way with no facilities to handle MM/MI cartridges, even those LOMC phono stages cames ( even some today ) with impedance load different values choices coming from 100 ohms to 1k ( more or less. ) where no one came with the option to choose 47k. All these are facts not imagination as the " golden " boy ".
Problem with what he posted about is that the normal audiophile has low knowledge levels and tend to believe all those lies.
holmz the compliance issue developed by changes in load impedance already was answered in this thread. Obviously not important for a normal audiophile because does not affects neither the LOMC cartridge frequency response
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You let it go, to lazzy to read.
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@whistleraudio aka @holmz : I already made the " food " but you want that I " eat it " for you., no way.
You need to make your job.
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JC: " Tonearm cable inductance is typically dwarfed by the inductance of the cartridge signal coils (Lyra PhonoPipe cable inductance 0.75uH, Lyra Kleos coil inductance 9uH), so it makes no sense to reduce the cable inductance if the price to be paid is greater capacitance (which is usually what happens).
When authoring the documentation for our post-2009 cartridges, I went up as high as 600pF cable capacitance (to cover audiophiles who may keep their turntable in a separate room / closet). The official loading recommendations for the Delos, Kleos, Atlas, and Etna reflect this wide range of cable capacitances, and the inclusion of highly capacitive cables for special circumstances is why you may see loading values as low as 95 ohms suggested in our literature.
R.
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Dear friends: Stupidity exist over the world and certainly in this thread too.
" We use a Grado Gold " :
That’s a high compliance MI cartridge with a high frequency limit at around 55khz. Here a professional review pasted highligths of the Grado Gold:
""
The Grado Gold sits at the top of the Grado ‘colour’ cartridges. In this sense, the Grado Gold cartridge epitomises the sound that Grado is renowned for: a warm, full sound that tends to match especially well with vocal, jazz, classical and other forms of music that have rich arrangements. The Grado Gold is a ‘pick of the bunch’ version of the Grado Silver – one that is judged to be made with excellent quality and care.
The Grado Gold cartrige has a very warm, dark sounding midrange that results in your vinyl sounding like vinyl .....................................................This cartridge can be a little susceptible to hum. The Grado Gold cartridge review suggests that this is due to the design of the cantilever. When playing music the hum is not audible, but it will detract from some of the frequencies and result in less detail throughout those frequencies. ........................................................................................................................................... The Grado Gold is not the most spectacular tracker. Especially sudden changes such as sudden loud chords or grand detailed crescendos might result in some tracking errors. ..................""""
The sample reviewed was loaded at 47k as usually with this kind of Grado designs.
So, that election of cartridge trying to prove the HF mistraking can be no more poor or stupid for that load changes purpose:
" Its got no worries playing a 30KHz tone, but if we start loading the cartridge we can see the output level drop (with some distortion/noise apparently added),..........
Empirically speaking its easy to deduce that the load is affecting the ability of the stylus to trace the groove, which is why we see distortion as essentially the stylus is mistracking. ""
Really? the whole statements posted are false because the Grado Gold, with out loading changes, shows mistraking ! ! ! Go figure ! ? ! ?
Laughing for say the least, you make my day. Go a head ! !, be my guest. Tremendous post for every one can learns but you.
R.
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@noromance : " 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 issue. "
With no tracking issues, that Wayne measured and JC wihte papers shows, bandwindth/frequency response is not affected.
The OP, you or any one else can load their cartridges witrh the impedance that in each one system " sounds " the best with out worried on that electrical/mechanical load issue that no knows system can " detect " and even direct measures can’t. So why distress about? makes no sense .
Btw, @whistleraudio posted: " we need a real physicist here. " and is rigth: he need it.
R.
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Again: " To claim that the loading affects the measurable frequency response of the cartridge is bogus. "
He not named " bandwindht ".
You said: " less able to trace high frequencies. " any cartridge that's " less able " to trace HF change the frequencies where is less able to pick up the grooves information. But the issue is that you can't prove it with true facts/measures.
You follow with your tale at Munich but in at least 3 different threads in different internet forums where you, JC and I participated about and where you posted your same " tale " he never confirmed that agree in that " less able to track HF ".
With out facts and confirmation for me all that is a lie and false as Wayne proved.
R.
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@holmz : Be straight and tell me what exactly you want to tell me with:
" a spell check on Raul I think. "
R.
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@holmz : " He never posted that loading to hard a cartridge will cause stiffness to the cartridge cantilever enough to mistracking. "
I was who posted that only to clarify that J.Carr never support those false statements by atmasphere. Tha’s all.
" to which answered " with false statements. Good for you if that is what you was looking for.
I paste all those information coming for true experts for we audiophiles can learn and don’t believe in what " some one " is spreading every where with out facts.
Unfortunatelly we are part of these corrupted AHEE. Such is life but people have the rigth to learn out of that AHEE.
Btw, who is: whistleraudio that you show in your last post.
Anyway in your last statement seems to me that in some way we are in agreement on that issue. Good.
R.
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Dear @judsauce : Start with Benz advise at the end is the cartridge manufacturer and knows all around cartridge/tonearm/phono stage to achieve the best of each cartridge. So you can start with 470 ohms and test it with LP tracks that you know very well what should be its quality performance levels.
MF loaded his Cadenza Black in your phono stage review at 100 ohms and even at 47 ohm and he did not mentioned any single quality level bad performance because that cartridge loading.
Btw, @holmz , next I pasted what J.Carr ( Lyra cartridge designer ) posted about cartridge loading:
"" To claim that the loading affects the measurable frequency response of the cartridge is bogus. However, if inappropriate loading bathes the phono stage in copius amounts of high-frequency noise, it may start to distort (unless the designer implemented various techniques to make sure that this won't happen), and the result will likely be intermodulation distortion. ""
"" If the phono stage does not have high overload margin at ultrasonic frequencies, or not-so-favorable linearity at ultrasonic frequencies, the ultrasonic spike resulting from high-value resistive loads (the spike can be in excess of 30dB at 5-7MHz if the phono stage input termination is 10kohm or higher) can easily result in ringing and intermodulation distortion which will obscure real information.
But if the designer does give his phono stage high overload margin and good linearity at ultrasonic frequencies, the phono stage will treat the ultrasonic spike as simply another signal, and no intermodulation distortion products will be generated that could otherwise be low enough in frequency for the ear to hear. ""
He never posted that loading to hard a cartridge will cause stiffness to the cartridge cantilever enough to mistracking.
What I pasted is a JC conclusion with foundation in his white papers coming from 2018 where made a in deep analysis, modeling/simulations, with white papers including charts of the behavior of loading an LOMC cartridges with different impedance values along different capacitance values too.
Other gentleman that in the past works for Analog Devices been group leader there and where he made/designed several AD items proved in real time what JC said and that does not exist cartridge frequency response anomalies in any way:
"" 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 did not design the AD797. That was Scott Wurcer- a colleague at ADI ( Analog Devices competitor to TX/B&B ). and, incidentally, for whatever it's worth, also an ADI design fellow. However, I know the design quite well.
He and I were colleagues in the opamp group in the 80s. He focused on high performance relatively low frequency opamps such as the AD712 and then the AD797, amongst others.
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. Then he continue:
"" is why any of the purported effects of heavy resistive loading you state could be definitively true-
certainly NOT on TRACKING which is demonstrably FALSE based on IM tests on tracking performance that I have incidentally performed as a function of load.
( He measured and is the only gentleman I know he did it. )
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 issue.
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 etched image that many "high resolution" MC cartridges produce.
By the way, I constructed a model for the cartridge back EMF using Lenz's law and incorporated it into my simulations.
One of the "joys" of being an IC designer is the compulsion to measure/model everything! However, once the skills are developed it's relatively easy to do as long as someone else has done the hard work of producing suitable models to use. "
All those by this gentleman and J.Carr are facts, something proved not coming from theory or a book.
So, the next statements are totally false and a falacy:
" it will make the cantilever stiffer and less able to trace high frequencies. It can and does affect the interaction between the arm and cartridge (effective mass and mechanical resonance). "
@holmz , not only were proved the statements are totally false but who posted the statements never posted anywhere where he is sharing that false information any tests/measurements/facts to prove it and always only dead silence and not only that but it's just a little of common sense to know that information is false:
first effective mass is not affected and the existence of mechanical resonance for that false " stiffer " cantilever just can't happens at a level where can has a measured effects. Look, if we take a tonearm with 12gr. on EM and a cartridge with say 18cu on compliance and 10 grs. of weigth the tonearm resonance frequency is: 8hz.. Now, you have to change the cartridge compliance from 18cu to 15-14cu ( stiffer ) to change the resonance frequency to 9hz but that does not affects high frequencies.
It will be an stupidity by my self to follow post arguments against something false when exist real test/measurements that already proved are false..
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
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