My Investigations into materials selection for a Structure for a modern design Optical Read Cartridge has been taken elsewhere. Resulting in my successfully being given description that has been of great interest.
Given Description is wrote immediately after receiving, recorded to my very best recollection, which follows:
RIAA is present at the time of cutting a Master Disc.
A later process further into the Signal Travel through the signal path offers a RIAA correction, this is to be added to the signal for the further transfer through the Signal Path for gain to be added.
For a Cartridge that has Electromagnetic Inductance to convert kinetic energy to an electric impulse, there is recognised Linearity.
Linearity is resulting in a consistent outcome for the well documented and known equations that are regularly undertaken for multiple years.
Wire Type, Coil Windings for selected Wire and Magnet Strength are the Trilogy that enables a very accurate creation for what is to be the design.
Such accuracy for the design and the Linear constitutive relationship for the Magnetic Flux creates accurately predictable conditions.
This use of materials, and the limitations (tight control of the materials) for a design. Creates a condition that is able to be accurately predicted, and if it were not for another factor that works in conjunction would be Law.
The same accuracy for predictability creates the opportunity to predict the tight tolerance accuracy able to be produced for the downstream RIAA correction to be added.
Unpredictable/Inaccuracy is the only real variable to become an impediment to the prediction for the sent Signal to encounter RIAA correction.
It is also stated, there is also a Nonlinear function to be found in the Electromagnetic Inductance Cartridge design, but this is relating to distortion being produced and the unpredictable relationship between the B field and the Flux. The Precision of a Cartridges Assembly can substantially impact on the distortion that can be detected/measured, as changes to the positioning of critical parts impacts on the B Field / Flux relationship.
It is stated, one of the main reasons Same Model Cartridges have been known to be unique in their produced End Sound, is the result of the Cartridge assemblies being impossible to be duplicated to a micron precision accuracy for alignment and tensioning of critical parts that aid Magnetic Fields being generated on the Surface of the Wire and working in conjunction with the effects of Flux within the Wire.
It is stated, this is what the Ortofon FSE does as a role in a Cartridge, which assists with keeping B field/Flux as an improved predictable. Hence, Cartridges are able to be assembled for producing more consistent Magnetic Field/Flux Interface, resulting in improved management of distortion.
Hence, across Cartridge Measurements and comparison of an End Sound becomes noticeably improved in consistency.
The above and what is to follow, is the description offered to me by a valued friend, who has substantial knowledge of Electronics through Career and 60 Years dedication to Audio using the Vinyl LP as a Source Medium.
All description offered, I am willing to accept and totally contented with.
The Materials selected to create the structure to enable the Electromagnetic Induction Cartridge to function and the structure the critical parts of the assembled Cartridge is attached to. Are equally as beneficial to the Cartridge that is an Optical Read to create an electric impulse.
On a modern design Optical Read Cartridge the form of the Stylus will be beneficial to reduce distortion passed to the Cantilever if of a certain form, and also if of a certain form will be more effective at sending certain frequencies, giving such a frequency range a prominence over other ranges.
On a modern design Optical Read Cartridge the material selected for Cantilever will also be beneficial to being more compatible with frequency Transfer.
An Aluminium will be a material well suited to one area of acceleration and a particular range of a frequency transfer and Boron will be well suited to another area of acceleration and a particular range of a frequency transfer. Gemstones such as Sapphire and Diamond will also have their own influences on acceleration and range of frequency that is through the material optimised to be transferred.
It is stated, the Cartridge Body Materials used on a modern Optical Read Cartridge are not recognised for being as influential on this Cartridge Type as on the Electromagnetic Induction Design.
A Body on the latter Cartridge is also used to protect the Electromagnetic Production from external influences, which the former Cartridge is not needing a protection from.
Additionally, it is stated, the impact on perceiving Tonality Changes that a Body Material can have on a Electromagnetic Induction Cartridge is not known on a modern design Optical Read Cartridge due to the limitation of materials used to produce the Cartridge Bodies.
It is stated the purpose of certain Body materials to dampen/dissipate energies are with have equal value on both Cartridge Types.
Additional information supplied, from the same valued friend, where they have extensive knowledge of working with Photocells in their long career. Where most work undertaken is done under a NDA, has come from many years of having hands on experiences.
All description given, I am willing to accept, but my not being grounded in an education of such a type, leaves myself insufficient in knowledge to fully comprehend how the description given has been firmly expressed.
It is stated, where the modern design Optical Read Cartridge falls substantially short of the Coil Cartridge, relates to the Optical Read Cartridges Photocell.
The Photocell is Nonlinear.
A Nonlinear Photocell is not sharing consistency in its Nonlinearity across each individual part selected.
Inconsistencies on the Photo Operation of each used Photocell creates conditions that when equations are performed, there is always to be inaccuracy.
Creating a Predictable Outcome for a Calculation is not a possibility!
The intent to use pertinent information, resulting in a calculus that is achieving predictable equations is not able to be done!
This as a outcome of the Nonlinearity of a Photocell Read are well documented beyond this Post.
I have already referred to in my earliest Post on this matter as my having knowledge of concerns known for Photocells.
It is stated, unpredictability leaves quite a bit more than only the accuracy of the RIAA conversion as the concern!
Other concerns are to be overcome, which is only achievable by being able to have bespoke/custom produced circuitry for each issue created from the selected Photocell.
To Customise supporting ancillaries for each Photocell added to the Cartridge, is the only method to optimise each Cartridges function and get the best End Sound able to be produced from that particular Photocell.
One Photocell can easily be noticeably poorer to another and the End Sound evaluation from one Custom design for supporting ancillaries, when assessed to another using a much improved Photocell for the design purpose along with its one custom circuitry, is not going to result in a parity presentation.
It is stated, these noticeable differences are likely to be much more noticeable than the differences detected in a Electromagnetic Cartridge, when distortion differences are present through assembly and differences for the Flux being produced.
Each Cartridge with a Photocell will have to be evaluated and designed around the unique signature of the Nonlinear function of each unit selected.
Energizers in use will also need to be unique, customised as a design, for each Cartridges selected Photocell.
The RIAA correction is also needed to be investigated and each will be a design to be a unique circuit for each Photocell in use.
It is stated, that there is not a ubiquitous solution for the modern Optical Read Cartridge, each must be treated as individual to become optimised.
It is strongly suspected there is not a Energizer design yet produced, to be a variable design to enable optimisation as an interface for the Nonlinearity of each selected Photocell and unique RIAA correction required.
Modern design Cartridge Manufacturers are not communicating the Nonlinear issues relating to Photocell function, in a way that shows the concerns for being able to maintain consistency!
There is seemingly the understanding from all users of such Cartridges, their Cartridge has a Photocell that is a perfect mimic of other Photocells used on other Cartridges and all supporting ancillaries are absolutely correct as an interface.
It is stated, the ubiquitous design for the modern design Optical Read Cartridge, is as big a Roll of the Dice.
It is far removed from the ease of selecting the materials that can be calculated for and create the most Linear component as a completed assembly.
" In general, circuit functions with non-linear behaviour don’t have linearity properties! Which for designers striving for accuracy are navigating a world with craziness.
We humans have not come up with a general-purpose method to exactly solve non-linear equations for supporting circuits?
Each case being unique, requires a new type of circuit, requires mathematical techniques specific to theness that must undergo constant changes.
This endless approximating tends to drive everyone crazy when met with the challenge.
The usual approach to nonlinear circuits, is to bend over backwards to make it seem linear over at least some small range of operation.
For myself, I have discovered info that even though quite different to what I though was to be discussed has left me willing to conclude that the Materials commonly seen used for the Structure and general function of a modern design Optical Read Cartridge are offering a benefit.
It is now seeming to myself following given description.
That the extent of the design and selection for the use of materials to create a enabling structure for a modern design Optical Read Cartridge. Is to be met with an 'Archilles Heel'. There is much more required to be done beyond the selection of of Materials for the critical function and the Structure for the Cartridge. Other critical parts used in the design for creating the electrical impulse and correction for the RIAA for the modern design Optical Read Cartridge is a unique challenge to attain an optimised performance.
It does seem now, with the description given, that the investigation undertaken by a friend, over the past 18 Months, to discover Cartridge Technologies through Internally investigating a large range of models.
Which has resulted in seeing the value of certain designs used for a Cartridge build, as well as becoming convinced a custom design for a FSE type part is a part well worthy of using to tidy up Cartridges measurements and End Sound.
The custom FSE part can be added to an Ortofon Cartridge and other Brands Models that are compatible has from todays given descriptions a realised merit for its inclusion to work with a Magnetic Field / Magnetic Flux relationship that is being produced.
I am queued to have this custom part added, when the correct service agrees to undertake the work to the standard selected by the investigator / designer.
I eagerly anticipate the experience of a very much liked Cartridge with a new level of accurately predicted control for distortion being produced.
