Grace Level ll

Since my last post in this thread i have expanded my collection of Grace, currently using a very rare LEVEL II (LC-OFC) with Sapphire cantilever.

Finally took some nice pictures of my spare Grace LEVEL II (BR/MR) LC-OFC. This model comes with Boron Pipe cantilever and MicroRidge stylus tip. 

***The advantage of the Pure Boron Pipe Cantilever:

Somewhere in the high frequencies, every cartridge has an undesirable resonance point. Undesirable because there the frequency response curve climbs a sudden peak. If that peak is in the audible range, your records sound not as intended. That resonance frequency is determined by the total effective moving mass of the vibrating system - the summed masses of the diamond stylus and, most importantly, the cantilever and magnet, etc. To shift that harmful resonance frequency up into the high supersonics, the effective moving mass must be reduced to the lowest possible minimum. Also, too much effective moving mass increases the mechanical impedance, thereby negatively affecting the cartridge's tracing ability. This is why GRACE LEVEL II, in its top grade cartridge (BR/MR), uses a Pure Boron Pipe cantilever. Pure Boron, because among all feasible materials Boron has the optimum combination of hardness (close to diamond's), lightness and rigidity. Grace LEVEL II BR/MR achieves the ultra-low mass that you need for flat, extended frequency response up into the highest range. Flat response for natural, unadulterated, warm and thoroughly listenable music. The extreme difficulties of machining Boron to the tightest tolerances have been solved. Mouting holes for the stylus, for example, must be drilled not by machines but by laser beams.  

***The advantage of the Micro Ridge stylus tip:

MicroRidge stylus profile is the most advanced profile in the world today, modern cartridges with MicroRidge stylus cost many thousand dollars. Micro Ridge is very unique stylus which is polished into the unusual shape. It has microscopic curvature of contact surface with records. This makes Micro Ridge Stylus does not change the contact radius by the wear after long playing time. You can always listen to music by the new stylus. At the same time this curvature has the radius of only 2 microns. Due to this small figure, the reproduction sounds have very high definition, wide dynamic range and low distortion. Low equivalent moving mass and the very new stylus will show the new aspects in the reproduction sounds. Micro Ridge Stylus is the newest one that was born by the most advanced technology for video disc player systems. Grace LEVEL II BR/MR has the most advanced square nude crystal oriented MicroRidge diamond.

Both MC and MI types have lower moving mass than any MM, if that’s the holy grail in cartridge construction. Lately I’ve been listening to a B&O MMC1 that I bought several years ago in NOS condition. It has a hollow sapphire tube cantilever and a line contact stylus. Tracks at 1.0 gm. It’s a moving iron type. After only a few hours, it’s brilliant. I am rather shocked. 

Lately I’ve been listening to a B&O MMC1 that I bought several years ago in NOS condition. It has a hollow sapphire tube cantilever and a line contact stylus. Tracks at 1.0 gm. It’s a moving iron type. After only a few hours, it’s brilliant. I am rather shocked.

@lewm  I am not shocked that vintage cartridges are superior (but they are different too), the hollow pipe Sapphire is what SoundSmith using now, but a hollow Pipe Boron is another story, not available for retippers/vendors (see above). 

Grace hollow pipe boron cantilever looks like the Technics cantilever, but the diamond mounted on LEVEL II BR/MR through the laser drilled hole is MicroRidge (can be used for 2000 hrs). 

I've noticed people are paying crazy price for those overrated Technics cartridges (205mk4 or 100mk4 with its weak damper) but in my opinion this rare Grace LEVEL II BR/MR is a much better cartridge (i've tried them all). Grace has a MicroRidge stylus on Hollow Pipe Boron cantilever, but Technics has conventional elliptical tip. Grace does not have any single problem with damper. Unlike Technics with their weak suspension, Grace engineers made the right choice of damping material for suspension, so even after 30 years the damper is fine (i've tried so many different samples) ! There is nothing better in the Grace own line of cartridges than LEVEL II BR/MR. This particular model combine all the best features for its time (mid - late 80's)

I will continue with my own "research" about Grace LEVEL II

Interesting facts:

This is what Technics invented in the 70’s and improved in the 80’s making cartridges like 205c mk4 with very special Boron Pipe cantilever.
It’s nothing but a grown crystals of Pure Boron into a pipe configuration (wow). A tip mounting hole made using a laser beam.

BUT This is pretty much the same that another japanese company (Shinagawa Musen Co LTD) made in the mid 80’s with Grace LEVEL II BR/MR but with at least one serious advantage over the Technics. The difference is the type of the low mass stylus tip. When you comparing Technics Elliptical to the Grace MicroRidge you know that Elliptical simply can’t win (elliptical has very short lifespan).

This is a Micro Ridge shape under the microscope.

Furthermore, type of the cantilever and the whole moving mass is very important according to this Technics research published in their catalog. Here is the moving mass in relation with high frequency peak on this diagram again. They are comparing Boron Pipe to the Diamond Rod.

Personally i prefer Grace LEVEL II (Boron/MicroRidge) over the original Technics 205c mk4 (Borron/Elliptical). Tried 6 samples of Technics 205c mk4 and 4 samples of Grace LEVEL II. All Technics carts came with weak suspension/damper. All Grace cartridges came with perfect suspension/damper. Both carts have rare Hollow Pipe Boron with laser drilled holes for nude diamonds, but the MicroRidge tip looks shorter than Technics Elliptical tip and obviously has lower mass.

p.s. all pictures made by myself with the actual cartridges from my collection

Going deeper in technical information provided by Technics in their patent from 1979 i’m shocked how complicated in manufacturing can be one tiny part of the phono cartridge called the cantilever!

Boron is known to have a hardness next to that of diamond and a very large resistance to abrasion, so that it is useful e.g. for cutting tools, sliding components and bearings. Further, since it has a low density and a large elastic modulus, the elastic ratio is largest among all the presently known materials. This means that the sound wave propagation velocity in boron material is highest among the presently known materials, so that boron is particularly useful for a cantilever for supporting a pickup. This invention (patented in 1979 by Technics) relates to a boron cantilever and a method making the same, particularly to a boron pipe cantilever for supporting a pickup stylus for converting shape signals recorded on a recording medium to electric signals, and a method of producing such cantilevers with a high production yield. According to this invention, a boron cantilever, particularly a boron pipe cantilever having a high mechanical strength and an excellent elastic ratio, ε/ρ, can be obtained, where E is elastic modulus and ρ is density.

Some new facts (at least for me):

Technics was way ahead of its time when they invented amorphous Boron Pipe cantilever back in the 70’s. Generally, a pure amorphous boron layer is best in view of mechanical properties such as tensile strength. It has been found according to this invention that a stronger boron cantilever can be obtained by a boron multilayer pipe, in which each layer is in a limited thickness. The thickness of the wall of the pipe cantilever is determined by required weight of the cantilever, required acoustic properties, etc. It has been found according to this invention that a boron cantilever pipe having a certain wall thickness and composed of plural boron layers is stronger than a boron cantilever having the same wall thickness composed of a single boron layer.

Among various known methods for forming a boron layer, the CVD is considered to produce the best quality boron layer. However, commercially available boron fibers are sometimes mechanically weak due to porosities, inner strains, micro-cracks, etc. Further, when a metal substrate having an amorphous boron layer thereon is removed by, for example, etching the metal substrate, the amorphous layer sometimes gets broken. This is considered to be because of the inner strains in the boron layer.

A CVD-deposited boron multilayer on a metal substrate according to the finding of this invention is strong even after the removal of the metal substrate, and is good in appearance also. The thus prepared boron cantilever is excellent as a cantilever. In this case, the thickness of each amorphous boron layer in the multi-layer structure is preferably between 3 and 15 microns.

P.S.

Some of my Technics top of the line cartridges here.

But look at Technics Boron Pipe cantilever in comparison to the Grace LEVEL II Boron Pipe cantilever. These are the most expensive cantilevers made for phono cartridges in the 80’s. This type of cantilever (Grace) is not available for modern cartridge manufacturers, instead they are using inferior Boron Rod now (and mostly for expensive MC, not MM).