Killing sibilance distortion - VPI & Jubilee

Hello Goatwuss,
I'm glad that you 've come to that conclusion. As with what we corresponded through email, if we have carefully set up the combo (put together with educated guess of which might mate well with what) and it doesn't work after readjusting all the known parameters (VTA, VTF, Anti-skating, Azimuth..etc), time to move on and try different combo. I used to think that with more upscale cartridges, they HAVE TO track and sound much better than the cheaper ones (given that they all are possible good match for the arm). Boy ..was I wrong and the AT33PTG I recommended is a living proof, at least in the tracking part.
If this combo doesnt work out well, dont kill yourself over it with nano adjustment..the issue just wont go away. Try different cartridges or arms. It's all synergy.

Best,
Hoa.

By the way, I dont think you are too sensitive with distorted sibilance. It's unacceptable and it annoys the heck out of me too.

Hi Doug:

I agree with the overall theme of your post, but regarding the technical details of the "escape of energies at various frequencies from the generator as mechanical energy, rather than being converting into electrical signals", please allow me to clarify and expand.

Most cartridges are capable of converting the movements of the coils into electrical energy - it isn't an "either/or" choice between electrical or mechanical energy.

What actually happens is that while the mechanical energy from the stylus is fully able to drive the coils to generate electrical energy, the mechanical energy doesn't stop there, and keeps going deeper into the cartridge structure. The dampers behind the coils are designed to linearize mechanical resonances of the cantilever/core/coils so that the conversion of mechanical into electrical energy doesn't have any significant frequency-domain errors, but they are not powerful enough to completely burn off the mechanical energy that remains after the electrical conversion process has completed. I typically refer to this as "depleted energy", in the sense of depleted uranium (the stuff has finished its job, but what's left over is still strong enough to create plenty of problems).

The net result is the equivalent of a mechanical echo chamber inside the cartridge - where previous mechanical energy can reflect back and alter how the electrical generation of new signals.

The greater the number of mechanical interfaces in a cartridge, the more likely it is that complex internal reflections will occur, and the more complex those reflections they are, the more it is likely that they will sound not like echos or harmonic distortion, which is acceptable to the ear. but inharmonic or subharmonic distortion, which isn't. Many cartridges that I have looked at contain multiple such interfaces, such as between center yoke and rear yoke, between rear yoke and cartridge body, and sometimes there will even be an inner body and an outer body.

Designing the entire cartridge structure that follows after the coils and dampers as a stiff mechanical diode is a good way to minimize reflections and stop the coils from being corrupted by echo distortion, but since it doesn't alter the total amount of mechanical energy (only redistributes it away from the cartridge), the problem gets transferred to the tonearm. And depending on how well the tonearm is designed, dumping as much mechanical energy as possible into the tonearm (which is what the cartridge wants for optimal performance) may cause various sections of the tonearm to ring, with audible consequences. Pioneer published some articles on the issue of tonearm vibration handling in the 1980s, and came up with a solution that they called a Dynamic Resonance Adapter (DRA).

Whether the tonearm uses DRA technology or other techniques like laminated construction, energy-absorbent stuffing in the armtube, rigid materials that exhibit high internal loss factor et al, the tonearm headshell, armtube and bearing structures should be designed with substantial vibration-handling abilities in mind.

cheers and hth, jonathan carr

Jonathon,

Thanks for the clarifications and interior details. Very helpful in understanding why it's so difficult to tame problems like the OP's sibilance distortions. The Olympos, Titan and Helikon don't have this problem (on any arm I've heard them on), so we know the problem is solvable. The OP's experiment with an inexpensive MM having a fine stylus proves that's part of a (complex) solution. The fact that it sounds a bit dull and slow in other respects merely demonstates one way an inexpensive MM is not an Olympos, Titan or Helikon!

A minor clarification or two (nothing you don't know, better than I):

Most cartridges are capable of converting the movements of the coils into electrical energy - it isn't an "either/or" choice between electrical or mechanical energy.

1. All cartridges are capable of converting (some) movements of the coils into electrical energy - otherwise we wouldn't use them! ;-)

2. It actually is an either/or choice between electrical or mechanical energy. The energy created by any given stylus deflection cannot be lost. It can only be converted to other forms of energy, or not. Phono cartridges aren't capable of converting that mechanical energy to (say) chemical or nuclear energy, so it's pretty much a zero-sum game between electrical and mechanical (and heat, which from a molecular perspective might still be considered mechanical energy).

You know all that, so if I misunderstood that sentence please feel free to slap me awake.

Hi Doug & JC,
I follow this interaction of your ---- and I like to mention what might be know to you and is in some way mentioned.

Take the SAME cart, say a Lyra Dorian and fit it in a REGA 300 arm or say Pro-Ject 9c (carbon tube), switch off the phono pre and listen to what the arm does. You can hear it from meters! away how this mechanical energy is buzzing up these arms.

I put it in my SME V arm (on SME 10 'table), and --- you hear nothing! unless you put your ear VERY close to the tone arm.

It must be ALSO the *resonance* of the arm, right through the spectrum that creates this effect since the energy from the cart would not be able (in my opinion) to produce this effect.

Your comments are most welcome,
Axel

Is it possible that your cart is just at its limit during certain passages? I futzed with a Dynavector 20XL (on a VPI Scoutmaster), for a couple of years, (including using the Mint), and it still had tracking problems. While not actually jumping out of the groove, there were certain Lp's--especially passages with high, clanking piano, solo flute/horn, brass--which acquired a "papery" and "thin" sound. I have since purchased a Dynavector XX2 mk2 and even after hastily aligning it with VPI's own jig, I've not been able to make it so much as hiccup. It retains a purity of sound, transparency, roundness of tone, and semblance of air right down to the last inch of groove. I'm profoundly satisfied. I hasten to add the the Dyna 20 XL was a wonderful cart in its own right on about 95% of my collection.