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 9 responses by fsonicsmith

As I posted elsewhere recently, with my Lyra Etna Lamda and Manley Steelhead, unloading to 25 does produce a very euphonic lively sound with more "space" in all directions. But I can hear distortion-the type of distortion one hears when there is too much 2nd harmonic. It is very pleasant but you know it is not right. It is the audio equivalent of a carnival mirror. Too much loading and the sound becomes lifeless. 100K killed the sound. You have to strike a balance. For my Etna, it is 50K. But there are so many variables-VTA, cantilever-suspension break-in, the preamp, the tonearm cabling. I use Reed 3P arms with the cryo treated Firewire that runs straight from clips to RCA's. 
I do rue your gas, Raul. 
There is nothing in Daveyf's posts to indicate he is using an Etna Lambda or a Manley phono stage. You seem to be confusing me with him. Second, there is nothing in your link that even remotely addresses the issue. Are you inebriated when you post sir? It would explain much.
//S// Fsonicsmith Eating Raul. 
For my Etna, it is 50k" -  50 kohms is unloading, its higher than the standard 47k.
You are showing your ignorance Dover. 47K is not standard for a MC and not standard with the Etna Lambda, which I am listening to as I type this. 47K is the standard for MM. Not for MC. We vinyl junkies, for better or worse, refer to lower capacitance as unloading even though you are technically correct. Why is this? Because as you lower loading values, the cantilever is subject to less damping. At the end of the day it is damping and not technical numbers that counts. Someone who knows his stuff wrote this;
The loading that the owner adds is a resistor in parallel to the signal path. That means that the higher the value of that resistor, the LOWER the amount of loading. Higher loading (lower value of the resistor) tends to damp high frequency peaks. With modern cartridges, the peak is usually well into the ultrasonic range, so loading is not needed as much as was the case in the past to correct for peaks. Jonathan Carr, the designer and builder of Lyra cartridges is among those who believe that additional loading is not needed to damp such peaks and it takes away some of the extension and open and airy sound on top. However, even though the peak is outside of the normal hearing range, it can be high enough in amplitude to overload some phono stages. He believes that loading is more important for preventing such overloading than in taming the frequency response of cartridges. I tend to agree with this. I happen to have a phono stage that does not overload and I like to run my MC cartridges (Lyra Titan and Transfiguration Orpheus L) wide open.

Sometimes, loading helps to suppress RF interference. A friend had a Hovland preamp that was passing a lot of hashy noise. It turned out that the factory default loading was 100k (essentially no loading). When we increased loading, the noise went away.

There is absolutely no harm in utilizing any particular amount of loading so one can experiment. I tend to find that higher levels of loading, say any value lower than 100 ohms, makes the sound warmer, more bass prevalent and shut down on top. Also, the lower the resistor value, the lower the total output so that volume level will go down. As a very rough rule, with most cartridges, a load of about 125 to 150 works perfectly well, and no much difference is heard if a higher value resistor (lower loading) than that is used.


You are showing your ignorance Dover. 47K is not standard for a MC and not standard with the Etna Lambda, which I am listening to as I type this. 47K is the standard for MM. Not for MC.
Actually 47K is the standard input impedance for all phono sections, MM or LOMC.


LOMC cartridges often seem to need lower impedances, but this is really for the benefit of the phono preamp, not the cartridge, due to the reasons Jonathan Carr has talked about, mentioned earlier on this thread.


I've been telling people this for years. If your phono section does not have troubles with the RFI caused by most LOMC cartridges (and the capacitance of the tonearm cable) then 47K will sound just fine.

An additional side benefit will be less ticks and pops, since the phono preamp will generate ticks and pops if the input section is overloaded by the RFI at its input. It is for this reason that tubes have a distinct advantage over solid state, as its easier to designed a phono section using tubes that is hard to overload.
Ralph, as I have said many times you are a great asset and resource to this Board but when it comes to phono stage topics many including myself simply feel you are somehow losing the forest for the trees, to put it politely. First, Jonathan Carr never says anything remotely similar about optimum loading for his cartridges. I am looking at Jonathan Carr's loading chart that came with my Etna as I type this and depending upon the gain setting and the total capacitance of the tonearm wire in interaction with the phono stage and the recommended loading ranges between 104 and 340 ohms for 0dB gain and between 284 and 887 in the highest gain column of +6dB. 
But that is Jonathan Carr who sees things (rightly so) from the perspective of the cartridge manufacturer. Now lets talk about phono stage producers. They don't espouse charts, they talk about listening. Each phono stage manufacturer knows the attributes of their designs. My Manley Steelhead with built in step-up transformers is not going to behave the way a Sutherland 20-20 (just for example) will. 
To say that 47K is the standard or de facto or even starting-point loading for a LOMC is ludicrous. 
Actually 47K is the standard input impedance for all phono sections, MM or LOMC.
Perhaps Ralph is referring to "industry standards" which are like the  biological artifacts of teets on boars and tailbones on humans. Or better yet, like the silly 1996 standard set by the industry for headphone amps to have 120 ohm output impedance. The audio industry has a long sordid history of setting standards that made little sense other than being convenient at the time and then slavishly and stupidly following them for years until someone brave and brash yelled for truth. People like Charley Hansen for example. How I (and most all of us) miss Charley. 
@lewm 
Not angry at all-in fact Lewm-you are among a handful of regulars on this Board that I rely upon on all analog matters and respect as having greater grasp of technical issues than I do. 
I previously acknowledged to Dover that he was correct and that I had misspoke as to loading. 
As you know, the max load if you use one of the MC inputs on the Steelhead is 400 ohms, and it offers choices going down from there to 25 ohms minimum. I assume that is what you did in that case. The Lyra website says the Etna Lambda has 4.2 ohms internal impedance, so 25 ohms would be a bit on the low side for phono input resistance and your description of the aural effect makes a lot of sense in that context.  
Yes, I meant that 25 ohms on the Steelhead with the Etna (and my VdH Crimson before it) sounded loose and sloppy, 50 ohms sounds ok on the Etna and sounded best with my VdH Crimson, and 100 sounds best with the Etna Lambda in terms of sounding tight and controlled without all the life being sucked out of the music, which occurs at all higher levels. The lower settings are euphonic but distorted. And yes, I use the two MC inputs only and not the MM. And I knew and agree that my use of the term "internal step ups" was sloppy and loose too (pun) as Manley refers to them as both in the owners manual (though I may be wrong and maybe they use the term "autoformer" exclusively) but as you stated, without seeing a schematic, even an informed person like you would find it difficult to explain what is going on and why. 

Ralph-thank you for your very polite and informative response. I apologize for my strong words directed at you. 
I still maintain-righty or wrongly-that two things are at play with loading. One can argue that they are interrelated. One is preventing ringing/overload and another is changing the magnetically induced behavior of the cantilever. 
My own misstatements about higher loading values being the same as higher loading is a common one and a common source of confusion. I think that the confusion stems from loading being nothing more than a resistor placed between the signal wires-left and right-and ground. A high value resistor such as 47K means less loading because the circuit is left relatively open. The cartridge/cantilever sees no electro-magnetic mechanical "constraint" because the resistor is to ground. Conversely, a low resistor value comes close to a short circuit/complete connection between signal and ground causing the cantilever to become electromechanically constrained. 
Ralph and others talk about the cartridge/cantilever having "to do more work" at higher loading. Ralph explains;
Of course if you use the loading resistor option, you are asking the cartridge to do more work. If you're using 100 ohms as a loading resistor, that's a couple of orders of magnitude more work than if the cartridge is driving 47K. This results in the cantilever being stiffer- the same as what happens with a raw woofer if you short it out (they are both based on the same principle of operation). This is not a matter of debate, if you feel the desire to do so, take it up with Mr. Ohm. Ohm's Law cannot be defeated and isn't open to interpretation. If there is more current flowing, it has to come from somewhere and that somewhere is the motion of the stylus in the groove. So the fact that the cantilever gets stiffer is not controversial. Anyone versed in the art knows this- Jonathan Carr and I discussed this issue at the Munich Show a few years ago.
I will freely confess that I thought the loose and flabby sound I heard with the 25 and 50 ohm settings on my Steelhead was the result of a LESS STIFF cantilever and not a too-stiff cantilever as Ralph explains above. It does make sense-once one understands the higher resistor value being to ground-that the lower resistor value approaches a short circuit and that the cantilever becomes stiffer and less damped, not less stiff and more damped. Damping is the absorption/dissipation of energy. You all know that. Why a less damped cantilever results in loose, flabby sound and a highly damped cantilever results in lifeless sound is still a tough concept for me to get my head around. I think I know what Ralph means when he speaks of the cartridge and cantilever having "to do more work" with higher loading by using his raw woofer analogy and imagining having to create an electric signal by applying more mechanical force-not less-pushing on a close to a short-circuited and electromagnetically stiffened woofer cone to generate a given amount of electrical output but still-this does little to explain why a less damped (stiffer) cantilever sounds livelier and why a highly damped (loose) cantilever sounds lifeless. 
With Ken’s new 47 step volume control, luckily there is plenty of control and there should be no issue running up a few steps.
47 steps in attenuators seems to be another inexplicable industry standard.
Raul-you are quite the enigma. Sometimes it seems that you are arguing about things that you falsely perceive the rest of us are arguing about-but aren't-and at other times you seem to misunderstand the entire topic. We can be talking about the weather and you start talking about the meaning of life. You probably will misunderstand my analogy too. This might get hilarious. 
Even your signature line is grammatically flawed. It should be "Enjoy the music and not distortion". You are missing a critical word "and" and you have erroneously applied the plural to the word "distortion". And this is before I get to the fact that your premise that music can be recreated without distortion is fundamentally flawed and your apparent belief that some people only enjoy the [inherent] distortion to the exclusion of the attendant music is also absolutely flawed. 
I am willing to bet you would be a great guy to have a beer with in person but your online persona is so clouded by your poor grasp of English that things go sideways fast.