What innovative, unconventional cartridge designs can you recommend?


Most cartridges have a stylus and cantilever where the transducer (magnet, iron or coil) sits on the far end of the cantilever.  What other designs are there?

I am mindful of two designs which put the business end right on top of the stylus.  The first is the moving coil (MC) Audio Technica AT-ART1000 which places two tiny coils, each 0.9-mm diameter, with eight turns of wire directly above the stylus.  Australian price is about AUD-7000 and there apparently is a newer model, slightly less exxe. the ART1000X.  This has square coils for a bit more output, and threaded mounting holes.

A downside is that stylus replacement involves a factory maintenance program and the Australian website page describing this service does not exist.

Another design is optical, exemplified by DS Audio's range.  While these still need a stylus to trace the groove, the signal is produced by reading the intensity of light produced by a Light Emitting Diode (LED) hitting two sensors.  Between the LED and the sensors are two 'shades' mounted above the stylus which change the amount of light as the stylus vibrates.  These cartridges need a special "photo-stage" to replace the conventional phono-stage which is an additional expense.

Australian prices including photo-stages range from AUD-2,150 for the DS-E1 to the DS Master 3 at approximately AUD-40,800, which is a bit outside my price range!  Where is the sweet spot?

What other way-out designs are there?

richardbrand

@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.

 

Completely Misunderstood.

But Thank You for reiterating the close comparisons already stated for the Cart' that does not Optically Read Shadow.

I am not the Foe of the Optical Cartridge, I am simply a individual who having experienced them is use on a familiar system at the time. Ended Up not being impressed to the place the design become an item to pursue. I

I understand enough about fundamental requirements for the optimal function of Mechanical and Optical Sensors, to know the Optical Sensor Cartridge mimicking the traditional Cartridge Design, is easily questionable.

As stated, the Optical Sensor Cartridge is presented in a form where it is immediately familiar to those that see it. This assists with the not immediately understanding the design for processing a Signal to undergo other stages of adding gain. Which when better understood, leads to Shadow being read to create a conversion to electrical energy.

Someone will be much much better for explaining why Sputtered Titanium is seen to be the most optimal for creating a Form that will be beneficial to a Optical Read of a Shadow????   

The Net is Cast for Wiser Fish to share Input.

The DS Audio is no different to any other cartridge in that it measures the groove using a suspended cantilever/stylus mounted in a cartridge body. The only difference is that it uses an optical system to generate an output voltage instead of coils/magnets etc.

Therefore any change to housing, suspension, cantilever material or stylus profile that can improve rigidity, tracking ability, or reduce tracing distortion will be clearly audible.

This is not rocket science.

@dover Your statement is far from convincing and your usual, I am the authority demeanour is clearly missing from the context of your comments.

An Optical System on a modern design Optical Cartridge measures shadow. How does Materials, such as the use of a Diamond Cantilever effect the Shadow being read??

How does the Stylus form or Body Material effect the Electrons being released within the Photocell to a quantity that enables a charge to be sent as a Electrical Impulse??

A Transducer that is using electromagnetic induction principles with data received as adulterated in condition as can possibly be achieved is a design well known how certain material selected offer improved benefits on how the sent energy impacts on the Magnetic Field that is generated.

Ortofon are so on top of the importance of the function of the Magnet Field, they have designed the FSE to create a uniformity / a gathering of the parameters the Field works within.

Where is the evidence that suggests LED and Photo Cells reading 'Shadow' to produce a increased Electron Count resulting in a electrical impulse to be transported for adding gain. Is a technology that is Equipollent to a Mechanical Energy Transfer effecting a Transducer whilst producing an electrical impulse to be transferred for adding gain. 

I can't answer these inquiries, but there is somebody who can, definitely not the usual contributor to the Gons Analog Section. 

For myself, I have no willingness to accept descriptions that imply that the Typical Cart' design where electromagnetic fields are produced, has identical impact on each system.