A question of loading...


I have just replaced my aging tube preamp with a new model. When I was using my older model with tube phono stage, I would run my Lyra Kleos and other MC cartridges with a load of 750 ohms. So, I assumed that with my new tube phono stage, which also utilizes a transformer in the phono stage and is also built into my new preamp, that the same cartridge loading would apply. I listened to the Kleos for about a week with this loading, and frankly, while it was fine, I wasn’t bowled over. Tonight I decided to experiment, so the first thing I did was to run the cartridge straight in, with no loading plugs. WOW, the increase in overall musicality and soundstage width was eye opening! Lesson learned is that not all gear is going to react the same when it comes to cartridge loading, particularly if there is a transformer involved and even if you are using the same cartridge from one phono stage to the next! An eye opener, anyone else experience something like this?
128x128daveyf

Showing 13 responses by rauliruegas

Dear @fsonicsmith  : At least I'm not a lier. Thank's for your post.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
Dear @daveyf  @fsonicsmith  and friends:  Why I don't took in count before:

in the thread where J.Carr shared his white papers ( load impedance/capacitance/inductance. ) and where he posted 6-7 times and in the Agon 2018 thread I mentioned J.Carr not even did mention about that cartridge mistracking behavior but he no where in any thread and certainly not in the WBT one J:Carr never mentioned not even near about that " increment of clicks and pops " ! ! !   GO figure  ""

That " clicks and pops " is a big and false tale/lie/disinformation/fraud or just name it as you want it.

Additional to that does not exist all over the internet any white papers about both subjects. DOES NOT EXIST NOTHING AT ALL ! ! !  No measures of any kind about even that in the two other threads and in this one some of us asked for and he just as always: dead silence because has nothing in hand that can prove it. Period and I mean it.

It's incredible to been discussing seriously both subjects and no one exist ! ! ! 

Next info is what J.Carr posted about the consequences that we can read in his white papers:


""  As most phono stages are designed are right now, the input resistor needs to serve two functions. The sonically dominating function is to make sure that the resonant ultrasonic spike isn't so large that it affects the behaviour of the phono stage. The sonically lesser function is to load the cartridge. I would like to see these two functions separated so that we can start discussing cartridge loading in terms of what it does for the cartridge, rather than as a phono stage band-aid in disguise.

How heavily contaminated (or not) your audio system's environment is by conducted and airborne noise in the frequency-peaking bands will also play a role.


 if some electronic component in your house is producing RF, this could preclude you from using higher resistive values for loading.  """



Now I can really laugh of that biggest audio " tale/lie " in the all audio history and now I understand why JC don't supported that man and his " tale ". Pity for say the least.


Regards and enjoy the MUSIC NOT DISTORTIONS,
R.




Dear @daveyf  : Yes, any cartridge can't track the LP grooves in precise way but not for the loading but because all imperfections that the analog alternative has. Pivoted tonearms does not helps but increment the tracking problems and the LT too.

There are several threads where we discussed all what is happening down there at the stylus tip during playing and it's " terrible " for say the least.

MC are almost immune to impedance loading. Problem is not there, but yes a cartridge always performs with mistracking but if we can detect the mistracking in the cartridge play behavior then something is wrong in the overall set up or the cartridge tracking abilities are poor. Again, loading is out of that mistracking.

Even with all the analog alternative imperfections I know we have a lot of fun with or at least we are accustom to.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
Instead 12cu we need 9cu. Frequency pass from 10hz to 9hz that's not enough for the cartridge been affected in its tracking abilities and the tonearm/cartridge behavior is not altered.

Other curious things that happened with you in those threads in 2018 is that in both threads JC participated and in both threads he not supported with a post the conversation you said took place in Munich when talked about that low load impedance consequences. Weird.

Curious too that JC even that he participated in the Agon 2018 he posted nothing when wyn posted FALSE about tracking.

Such is life.

I think is enough. If we learn something through this thread good and if not maybe helps to confirm what we already knew. All we win and no body defeated.

R.
In 2018 thread where wyn posted and before the first wyn post you posted not one but twice:

""" When you load at a very low value (like less than 100 ohms) its possible to reduce the cartridge output and also decrease high frequency tracking abilities. ( Btw, wyn runs his mandake at 60 ohms and performs fabolous. Obviously no tracking issues. )


"" the cartridge is asked to perform more work as it has to drive the lower resistance. This makes the cartridge cantilever stiffer and less able to track higher frequencies. This is why the resistor can act as a tone control. ""


Curious that in that thread that after the first wyn post there you left alone almarg ( who was supporting you. ) and you did not post nothing again about that cartridge tracking issues not even when wyn posted was FALSE because he measured.

In the other side and in the Etna/Kuzma resonance frequency it needs 3 compliance unit to change its frequency resonance and instead of 12cu we need 10cu. Again how much current is need it to happens that?

R.
atmasphere :  ""   If what you say (that loading the cartridge has no effect on the stiffness of the cantilever),... ""

that's not what I'm saying even if I did not explain it in the rigth way.

What I'm saying is what i posted:


"2   stiffness to the cartridge cantilever enough to mistracking. ""

the key in that statement is: " enough ", this is what I'm saying and in his technical words Wyn too.

Two years ago here and in the other forum I told you the same: how much current has to pass through to stiffness the cantilever enough to the cartridge mistracking?

In those oboth forums I told you that for the mistracking could happens the cartridge compliance has to change a lot of compliance units and here in the Etna/Kuzma real example you need to pass from 12cu to 7cu to be out of the ideal resonance frequency range but that does not means for sure that will be a mistracking down there.

The issue is that mistracking not that cantilever stiffness. It's you who need to prove with measures that can gives the rigth answer to that question I made it two years ago and that you never answer.

R.
Dear @daveyf  : As many of us I'm sure you know the Hagerman calculator  that's an old cartridge tool that explains several issues that J.Carr expanded and goes deeper than Hagerman.

As in the past threads here and in other forums everything is clear but the cartridge mistracking where Wyn measures and he was really emphatic:

"   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. "  "

All what JC developed was in order and learning white papers for any audiophile.

The  issue that's false is that  exist mistracking when more current running through the cartridge.

Any one of us can do/run a tests  with our today set up making load impedance changes ( and everything the same not touching any other parameter. ) and I'm totally sure that no one will dtect or find out a mistracking due to any of those individual load impedance changes.  

The test is not looking if the sound is better or not but if exist a mistracking or not. Obviously listening an LP tracks where we already know the today cartridge has no tracking issues.
Perhaps the only characteristic that we can detect could be that with 100 ohms or lower the SPL will goes a little lower or other characteristics not related with mistracking that is what we are looking for.

R.


"" 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 that did it. )

Pick-up your measures and come back to talk with Wyn. Btw, 2 years ago you had the opportunity to post in that thread but you did not do it.

You posted several times there ( two years ago. ) but when wyn posted what you are reading here you just " dead silence ", not even JC posted to refute Wyn measures and he posted at least one time in that same thread. That attitude from you speaks by it self more than thousands of words.

" that there were any white papers. But FWIW they aren’t needed;..."

well Wyn thinks different and he proved. You, as almost always just: bla, bla, bla, with out facts, exactly as two years ago. Measures is a fact .

Anoher anecdotal: at A.Porter place he was running his low impedance MC cartrige around 400-500 and when I listened to it ( I/O phono stage. ) I told him that something was wrong with and I suggested to change the load impedance to 100 ohms and the cartridge quality performance " shines as never before " ( this was the AP words. ) and yes : nigth and day change for the better.

Btw:  ""  The 'more dynamic the sound' bit is false though.  "

Don't claim/tell to me but to Ortofon and do the same with M.Huber at FM Acoustics. Not to me.


R.



Dear @fsonicsmith  : In 2018 J.Carr 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.

He he did not shared the information in this forum but in other different to Agon and I took from there highligths of what he posted about:

""  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. Was other gentleman in that forum who posted that he talked with JC and he understand him that kind of statement.

In the other side JC never said he had white papers of that cantilever stifness as a consequence of the cartridge loading, not even gave any single example with any of his cartridges or other ones where he measured that issue, so no measures about by him and certainly not for any one in this thread.

Now, by coincidence in that same year here in Agon the MC loading was the main subject in a thread ( exist other threads with the same subject. ) and the discussion was more or less that here in this thread but in that thread participated an Agon new comer with several posts, named Wyn and these are what he posted on him self for we can know about:



"""  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.

The idea of driving a cartridge directly into the virtual ground of an amp either just using the amp input impedance (such as a grounded base transistor) or via a resistor is hardly a new one. Some of the earliest solid state phono stages did exactly that, including one that I sold in the UK in the 1970s. I also used a transimpedance op amp that I designed (the AD846) in that mode- using the device as a current conveyor and operating it both closed and open loop as the extraordinarily high impedance "compensation node" could be loaded by a resistor to provide a fixed, and low, transimpedance for the stage.
I can't say that either approach seemed to be particularly successful ""

He is now retired and living in England and he worked too in the recording industry.
Wyn as any other engeneering at ADI or TX is a engeneering handbook walking.

So, in that thread the issue arrived as here to that cartridge stifness mechanical phenomenom caused by that hard loading issue and after several posts he posted this:


""  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.
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.  

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.
Constructing an electrical model for the Madake was fraught with concern as using my own meters to measure the capacitance and inductance was anxiety producing.
Then when I plugged the parameters into the simulation and compared against my measured output I realized that the actual response had precious little to do with the electrical characteristics and everything to do with the mechanical resonances.
And so, the journey began..."""


No one in that thread including atmasphere refuted him. How can any one refute facts/measured information, no way.

Other than FM Acoustics in that different forum where JC posted in the same thread we can read what ORTOFON said about:


"  And here's an interesting comment from Ortofon to me (in a private discussion with them) - it clearly goes against what Jonathan and I have said:

[FONT=&amp]Playing with the input impedance means also playing with the sound character. The influence of the load impedance on the differences in sound is caused by the change of the crosstalk levels and the amplitude raise at the resonance frequency. The lower the load impedance, the higher the current and the more dynamic the sound.[/FONT]   """


Only as an example. If we take the Lyra Etna mated with the Kuzma 4 point tonearm the cartridge cantilever 12cu ( compliance ) has to go to 7cu to stays out of the resonance frequency range. No sense that that loadibng electrical current can stiffness in that way to change from 12cu to 7cu for the possibility of some mistracking that can or can't really occur.

My first hand experiences says that with my phonolinepreamp and in the past with the Classé Audio DR-7 loading at 100 ohms and never happens a mistracking because that kind of loading maybe just the SPL goes a little lower and nothing more.


Regards and enjoy the MUSIC NOT DISTORTIONS,
R.





Dear @daveyf  : There is no single advantage, today SS phono stages just can't be overloaded in normal condition: comes with very good headroom. That " problem " was a " problem " of the past/several years ago. Everything change SS manufacturers move on because they learn too, they are not sticked in the past as atmasphere.

In the other side in his last post @fsonicsmith is just rigth and if we read the page 3 and 4 in the FM Acoustics link data sheet M.Huber point out easy and important information about.

Atmasphere is sticked with his very old opinion and in several threads here or in WBT was defeated but is his privilege to be sticked there: just does not moves. Who cares? .

Yes, in other audio subjects he is a very good resource as @fsonicsmith  says.

R.
Dear @fsonicsmith  : I know what I posted perfectly, no problem with.

I took what you posted only as an example of what M.Huber states in his site but I know that you not download the information about that's pertinent to that 50K/Manley combination.

Read again what I posted to Davey and you will know you are wrong on your statement.

R.
Dear @daveyf : This is a " little " diferent point of view of M.Huber designer and owner of FM Acoustics about MC loading:

https://www.fmacoustics.com/products/phono-linearizers/fm-223/

just download the data sheet information at the end of the page.

His unit is a unique design.

According that that loading of the Etna Lamda at 50K says the design problem that Manley unit has as any other phono stage design where the owners needs that kind of loading values to achieve a decent sound reproduction.

In my system unit that just does not happens and that’s why I never need to use that kind of loading figure. I tested it and that's why I said that.

R.
Dear @solypsa : I think closed a few years ago. Excellent electronics designs.


http://www.klyne.com/pages/system7.html


this was its phone:

Klyne Audio ArtsOlympia, WA 98501(360) 273-8477


and here you can read the cartridge loading through Klyne  unit:

https://www.techtrader.ch/auction/2016/03/Klyne-7-PX_B-3.5.3-manual.pdf


Regards and enjoy the MUSIC NOT DISTORTIONS,
R.