Excel Sound has launched the Hana Umami Black pickup cartridge at its recent Hana G6 summit in California, held to celebrate the company's 55th anniversary. Speaking with hi-fi+, Masahiro Okada - son of Excel Sound founder Masao Okada - outlined the engineering choices behind the new flagship model and his transition toward leading product development.
Masao Okada founded Excel Sound in Tokyo in 1970 to manufacture pickup cartridges, originally focusing on OEM production for outside brands. In 2015, the company's export and sales agency, YouTek, encouraged the founder to build cartridges under its own brand, Hana.
According to Masahiro Okada, third-party OEM manufacturing has since dropped to roughly 20% of Excel Sound's total output, with the vast majority dedicated to Hana. While he initially handled sales, he told hi-fi+ that he will now focus on product development alongside his father in research and development, drawing on all of the company's technological and development capabilities.
OKD Magnetic Generator Assembly
At the core of the Umami Black is a new OKD magnetic generator assembly. Unlike the other two models in the three-part Umami lineup, the Umami Black is the only one to use a neodymium-boron-iron rare-earth magnet.
The OKD generator combines the rear yoke and pole piece into a single manufactured piece, which Excel Sound states is a world first. In the Umami Red and Umami Blue cartridges, those two parts are glued together.
The rear yoke and pole piece are manufactured as one piece to prevent any kind of mechanical vibration or loss of magnetic energy. In the Umami Red and the Blue they are glued together. This aspect of the design is very important - to have it as one block.
Masahiro Okada, Excel Sound
The Umami Black also introduces a front pole piece that is unique within the range, featuring a U-shaped cutout where the cantilever and armature assembly sits. Although Masahiro Okada noted that the exact mechanics of the U-shaped front yoke are a trade secret, he told hi-fi+ that it “optimises energy transfer, minimises magnetic energy loss, and reduces unwanted mechanical resonances.”
In addition, every part of the magnetic circuit - including the terminal pins - undergoes cryogenic treatment, a process used across cartridge, transformer, and loudspeaker manufacturing to improve permeability and crystalline structure. According to Masahiro Okada, Excel Sound first introduced cryogenic treatment on its ML model and applies it to several cartridges across its lineup:
- ML
- Umami Red
- Umami Blue
- MkII SL
- MkII SH
- EH
He added that all Hana cartridges will use cryogenic treatment going forward to improve both the components and the metal quality.
Hybrid Carbon Armature and Third-Party Manufacturing
At the end of the cantilever, the Umami Black uses a new cross-shaped, square hybrid carbon armature where the coils are wound. While Excel Sound uses a mix of semi-automatic machine winding and hand-winding across its production, Masahiro Okada explained that the square hybrid armature in the Umami Black requires hand-winding.
Skilled artisans at Excel Sound hand-assemble every aspect of the Umami Black. However, the company does not fabricate the individual raw parts in-house.
Instead, external specialist manufacturers produce all component parts - including the cantilever assembly - to Excel Sound's specifications, as they require highly precise production technology.
Diamond Cantilever
For its flagship cartridge, Excel Sound selected a diamond cantilever. Masahiro Okada noted that Japan has two major cantilever assembly manufacturers, and Masao Okada provided the specifications to the supplier with whom he has built a strong relationship.
Masahiro Okada told hi-fi+ that while many moving coil cartridges on the market already use diamond cantilevers, pairing the material with the Masao Okada-developed OKD generator makes the most of it. “Diamond is the hardest possible material and ideal for signal transfer and its exceptional rigidity ensures direct and precise transmission of groove modulations, preserving every detail and dynamic shift with astonishing clarity,” he said.
Magnet Selection and Global Availability
Each model in the Umami trio uses a different magnet material: neodymium in the Umami Black, samarium cobalt in the Umami Red, and alnico in the Umami Blue. While Masahiro Okada said many reasons behind the choice remain closely guarded trade secrets, he noted that his father's research found that flux deviations in magnetic material affect overall cartridge quality.
Using a stronger neodymium magnet also allowed Excel Sound to reduce the number of coil windings in the Umami Black. According to hi-fi+, this reduction lowers the moving mass and brings the internal impedance down to five ohms.
Hana cartridges are currently sold in 60 countries, led by the top-selling SL models and closely followed by the ML.
Manufacturer
The Hana brand is produced by Excel Sound Corporation (excelsound.jp).
This article was written by AI from reporting by hifiplus.com.
