What innovative, unconventional cartridge designs can you recommend?

@richardbrand the 70mv output doesn’t require tremendous gain from phono stage which also contributes to overall lower noise floor. It should be a sublime listening experience when you receive and install the cartridge. Looking forward to that. 

I'm happy to be proven wrong, expose myself to the Public Humiliation through being wrong, but there is plenty that can be read that relays info, that in general is stating. Optical and Mechanical Sensors are in need of quite different requirements for their function to be optimised. It is quite easy to discover that a sensor using mechanical energy transferral is a high risk for accuracy when ambient kinetic energy is able to pass through the sensor structure. These same concerns are not to be found for Optical Sensors being used.

Moving the above to the Phono Cartridge poses discussion worthwhile being seen by a broader audience and home truths being discovered. 

Question - An Optical Sensor has zero similarity to an Analogue Sensor when it comes down to an Ambient Kinetic Energy transferring through the Structure that enables the sensors to function.

The Form of the Stylus in contact with Groove Modulus, has an effect on the way the Groove Modulus is passed, which can have an impact on the shadow produced by an Optical Cartridge Read of a produced shadow?

The idea of Diamond - Boron - Aluminium having an influence on the Optical Read makes no sense to myself, how are shadows being read influenced for the better by different materials used as the conduit for energy transfer?

The idea of Aluminium - Duraluminium - Titanium - Wood having a influence on the Optical Read make no sense to myself, how are shadows being read influenced for the better by different materials used as the Body of the structure housing the parts that receive the transferral of produced energy? 

How does Shadow being read become an adulterated signal read, through local Ambient Energy energies being transferred through the enabling structure, outside of energy created from Groove Modulation?

It seems to me, the recent produced Optical Cartridges are designed to be familiar within the world of Phono Cartridges. Where materials selected for creating the enabling structure and modulus interface are recognised for their value and pricing in the non-Optical Cartridge Market.

These materials selections for Optical Cartridges enable comparative pricing to Mechanical Interface / Kinetic Energy Designs, resulting in creating Large Expense Sale Items. 

Prove this wrong - Weight of overall structure and an assembly of enabling parts that is compatible with commonly used geometry for Cartridge Set Up, is all that is required to get the optimal performance from a modern design Optical Read Cartridge.

Bring It On  

@audphile1

I was thinking of the Koetsu Blue Lace. In a whole other league of course. But listening to the DS003 reminded me of another more modest MC, the ZYX Atmos/4D. I got it out and the presentation was similar, smooth + detailed. The DS gave me a new appreciation for a cart I'd been ignoring for too long.

@pindac 

Prove this wrong - Weight of overall structure and an assembly of enabling parts that is compatible with commonly used geometry for Cartridge Set Up, is all that is required to get the optimal performance from a modern design Optical Read Cartridge

DS Audio optical cartridges in many ways are similar to conventional MM and MC cartridges.  They all have a stylus, cantilever and armature, which should be familiar to any audiophile.  They share the same geometry for ideal set up, requiring the stylus rake angle, vertical tracking force, azimuth, zenith and vertical and horizontal tracking angles to be optimised.  DS Audio cartridge weights are remarkably similar: 7.7, 7.7, 7.9, 7.9, 7.7 and 7.7 grams from the top down in my list posted above. The difference is probably paint! Optimal tracking force is 2.1 grams for all current DS Audio cartridges.

The same sorts of styli trace the recorded groove as conventional cartridges.  A major consideration here is the effective tip mass measured at the stylus.  The best tracking requires the lowest tip mass, which can accelerate the fastest to "hug the groove".  Anything added to the basic stylus / cantilever / armature adversely affects the trackability.  In LOMC designs, the ART1000 goes to extremes to minimise the added mass, with two tiny coils mounted just above the stylus.  Current DS Audio cartridges add two 'sails' of extremely light beryllium on the cantilever just behind the stylus.  Most MM and MC designs have relatively massive magnets and coils at the other end of the armature.

The idea of Diamond - Boron - Aluminium having an influence on the Optical Read makes no sense to myself, how are shadows being read influenced for the better by different materials used as the conduit for energy transfer?

The shape of the stylus is important in DS Audio optical cartridges, like in any cartridge. Probably of equal importance is the mass and rigidity of the cantilever.  Lithium, beryllium and boron are the lightest metals, with aluminium about twice as dense as boron.  Lithium is highly reactive, and beryllium is brittle and toxic.

The real question is how quickly does the position of the beryllium shades change in response to groove modulation.

Carbon is just one up from boron in the periodic table, and in its diamond form, is the hardest naturally occurring substance known to man.  Techniques for growing large diamonds from vapour have allowed DS Audio to grow a single diamond to form both the stylus and cantilever in its top model, Presumably this improves rigidity and reduces resonances.  

Energy transfer from the stylus to magnet and coil structures is what drives the signal in conventional cartridges.  The signal corresponds to the acceleration of the stylus.

Question - An Optical Sensor has zero similarity to an Analogue Sensor when it comes down to an Ambient Kinetic Energy transferring through the Structure that enables the sensors to function

With optical cartridges, there is no energy transferred from the stylus.  Instead external power drives Light Emitting Diodes (infra red actually) and the signal is generated by photoelectric sensors, all housed in the cartridge body.  The signal is dependent on the position of the beryllium shades, so a completely different equaliser stage is needed.  Weight and geometry are far from the entire story! 

@pindac

The idea of Aluminium - Duraluminium - Titanium - Wood having a influence on the Optical Read make no sense to myself, how are shadows being read influenced for the better by different materials used as the Body of the structure housing the parts that receive the transferral of produced energy? 

This surely must be about vibrations from the stylus, and how they react with the body of the cartridge.  If the body of the cartridge vibrates relative to the stylus, there is a potential feedback loop which will amplify the differences.

DS Audio mentions three types of aluminium alloy in their cartridge bodies.  The tensile strength of A5052 is not much more than a third of "ultra duralumin" which I guess is probably Ultra-Super Duralumin - A7075. A5052 is mainly alloyed with magnesium, and is highly corrosion resistant. Duralumin is mainly alloyed with copper, and is normally faced with purer aluminium to minimise corrosion.

A5052 has better internal damping characteristics than A7075, which also has higher resonance frequencies.  My guess is that these do make a slight difference?

Now, when we come to other materials like titanium and a number of exotic woods, the internal damping and resonance patterns will change again.  Stone will also have different characteristics.

Notice that the DS Audio cartridges have rounded shapes, which probably help to minimise reflections.

Wilson Benesch has a titanium cartridge body which is laser fused from titanium powder into a complex structure designed to minimise resonances and channel what remains away from the stylus: TESSELLATE Ti Cartridge

I can see no reason whatsoever why ruby should sound better than sapphire - they are fundamentally the same material with different impurities.