A retired engineer and a core material.

My Sonic Lab is a small Japanese maker of moving-coil cartridges and step-up transformers. Its Japanese website, mysonic.jp, names Yoshio Matsudaira as its representative, at an address in Itabashi, Tokyo. The site dates the brand’s debut to the Eminent cartridge, announced in the autumn of 2003 and on sale from that December; the website of its American distributor gives 2004 as the founding year, so we give both.

The origin story is Matsudaira’s own. In a column on the Japanese site he writes that his interest in low-impedance moving-coil cartridges began in the mid-1960s, when the late Masaru Okahara told him that a cartridge is a generator, so its impedance must be low. Lowering impedance means fewer turns of wire on the coil and so lower output, and he spent, by his account, more than twenty years looking for a magnetic core material that would let him have both. Working with a researcher who developed core materials for step-up transformers, he reached what he later named SH-μX in the late 1990s — but, he writes, his employer saw no point in testing an analogue product at the height of the digital era. He retired in 2000, fell ill, and decided while recovering to finish the work on his own.

The column does not name that employer. The fuller career story comes from the distributor: in 2018 Jonathan Derda of MoFi Distribution, which handles My Sonic Lab in the United States, told Stereophile that Matsudaira had met Yoshiaki Sugano at Supex, worked with him on the original Koetsu Onyx, designed a cartridge for Luxman, and later designed and made cartridges for Air Tight while working for Audio Craft. We have not been able to confirm those claims independently.

Low impedance, high output.

The brand’s motto, printed on its Japanese homepage, is “low source impedance, high output energy.” The argument behind it is technical. Moving-coil cartridges with iron cores usually use either pure iron, which can carry a strong magnetic field but responds poorly to small signals, or permalloy, which responds well but saturates early. The company says SH-μX combines a saturation flux density of 1.5 tesla with an initial permeability of 100,000 — figures it publishes itself, and which we have not seen tested independently. In practice, it says, the core lets it wind fewer turns of wire and still get usable output.

The specifications follow from that. The original Eminent had an internal impedance of 1.8 ohms and an output of 0.5mV, which the company calls a world first; the Ultra Eminent Bc of June 2008 went down to 0.6 ohms and 0.3mV, with a solid boron cantilever. Other models kept to the same line: the Eminent Solo mono cartridge of 2005, with two coils wound together so that the channels do not share a ground; the Hyper Eminent of 2007, with a base of A7075 aluminium alloy given an ion-hardening treatment; and the Signature Gold of October 2012, which the company presented as marking ten years since the Eminent, with an internal impedance of 1.4 ohms, a duralumin cantilever and a base finished with metal plating and a diamond-like carbon coating. The Japanese site says styli are bought as semi-assemblies and reworked in-house, and it also lists the Stage series of step-up transformers.

The range on the American distributor’s site adds the Signature Platinum, with a black ion-hardened titanium body and a boron cantilever, and the Eminent Ex, whose packaging, the site says, is made by Takamine Guitars.

Design and documentation.

These seven makers belong to a small trade. A phono cartridge is a few grams of magnet, coil and diamond, largely assembled by hand, yet only a few of these brands say who does the work.

Goldring, which traces its roots to Berlin in 1906, belongs to Armour Home Electronics of Bishop’s Stortford, a subsidiary of Q Acoustics Limited, Companies House records show. It says its cartridges are “designed and handmade in the UK,” though its own history says it outsourced much component manufacturing in the 1990s. Soundsmith says every product is “hand-crafted” at its factory in Peekskill, New York.

Sumiko, the cartridge brand of a Berkeley, California, distributor bought by Fine Sounds of Milan in 2011, Stereophile reported, says all its cartridges are hand-built by Excel Sound in Yokohama.

Three are Japanese. Nagaoka, a family stylus maker based in Higashine, Yamagata, makes an MP-700 that is “still completely built by hand in Japan,” Hi-Fi News reported in 2025. ZYX works from Nagara in Chiba; its founder says he managed OEM cartridges for several makers at Namiki Precision Jewel before 1986. My Sonic Lab gives a Tokyo address; its US distributor, quoted by Stereophile in 2018, said founder Yoshio Matsudaira had earlier made cartridges for Air Tight.

Benz Micro, the Swiss name, is hardest to place: its website is a holding page, and the Swiss business-name index lists a Benz-Micro AG as deleted in 1997.

This guide sets out what can be checked about each brand — who founded it, who owns it, and what it says about where its products are made — and marks clearly what rests only on the company’s own word.

A motto, a material and a model name.

Independent coverage in English is thin. The most substantial we found is Herb Reichert’s Stereophile column of December 2018, which reviewed the Ultra Eminent Ex at $6,995 alongside the Stage 1030 step-up transformer. Reichert wrote that the cartridge sounded like analogue tape and achieved “believable corporeality” better than any DAC or other cartridge he knew, and described Matsudaira as the company’s founder and chief engineer. The same column relayed the distributor’s statement that Matsudaira “still does OEM/ODM for many of Japan’s top brands” — that is, that he makes cartridges sold under other names — which, like the rest of the career story, we could not check.

The company appears to remain Matsudaira’s own: we found no record of an acquisition or outside owner in the sources we checked, though we could not establish its legal form. Its Japanese website was last updated in 2013 and marks several products, including the original Eminent, as discontinued in August 2014. Readers should also know which site is which. Mysoniclab.com is the American distributor’s site, not the maker’s, and states that its images and content belong to MoFi Distribution; mysoniclab.jp showed only a web host’s placeholder page when we checked.

Where the cartridges are made is not spelled out on the pages we checked. The Japanese site describes reworking styli in-house and gives only its Tokyo address, so we say no more than that.

For a design guide, My Sonic Lab shows how one engineer’s idea can carry a whole brand: a motto, a material and a family of model names. Compare Koetsu, whose Onyx the distributor links to Matsudaira, and Dynavector, another Japanese moving-coil maker. For this guide we use titanium black, duralumin silver and a muted gold with a serif, an unofficial interpretation; no product or logo is reproduced.

Keep My Sonic Lab’s identity on hand — save it to a board in the Made Good inspiration library.