Editor’s Note
This article highlights Audio-Technica’s unique vertical integration in phono cartridge manufacturing, from diamond to generator, and introduces the 2025 AT33x series as its first major update in over a decade, promising enhanced audiophile performance.
Audio-Technica, the manufacturer of turntables and headphones, is one of the few companies in Japan to control the entire production chain for phono cartridges, from the diamond to the generator (MM/MC) and the cantilever. This is achieved with highly advanced engineering and near-watchmaking production quality. The new 2025 AT33x series of phono cartridges represents the first major evolution of the AT33x series since 2014. It brings genuine audiophile added value, particularly in terms of diamond size and construction precision.
This year, Audio-Technica has launched several highly audiophile and high-end products, including the transparent luxury turntable AT-LPA2, which we discovered at the Munich High End show, and the floating, luminous Hotaru turntable, sold for €10,000. The 2025 AT33x phono cartridge series comprises five models: the stereo cartridges AT33xMLB, AT33xMLD, and AT33xEN, as well as the mono cartridges AT33MONO/I and AT33MONO/II. These products are aimed at Audio-Technica customers who are not seeking High-End extravagance, but rather cutting-edge technical audiophile performance.
For the AT33xEN stereo cartridge, the Japanese brand has opted for a full elliptical diamond, aiming to offer rich playback and great mastery of sound reproduction. As for the AT33xMLD and AT33xMLB stereo cartridges, they use a Microlinear diamond. This extremely fine diamond type features a shape inspired by the engraving stylus that cuts master discs. The elongated tip of the Microlinear diamond thus follows the smallest undulations of the groove with a contact radius of about 2 microns and a longitudinal contact surface of about 75 microns. This ensures very precise high-frequency reading, low distortion at the end of the record, and more limited groove wear compared to other diamonds.
Finally, the AT33MONO/I and AT33MONO/II mono cartridges use a simpler “nude” conical diamond type, more suitable for playing mono vinyl records. In the case of these cartridges, the diamond’s movement is on a horizontal axis only, to limit any parasitic noise due to horizontal oscillations of the cantilever.
One of the major evolutions of the 2025 AT33x series compared to previous generations lies in the use of die-cast zinc. Audio-Technica chose this material for its high rigidity and significant density. It is used for the design of the base of the cartridges in this new series, as well as for their chassis, in combination with aluminum and highly rigid polymer.
These last two elements were already present on previously marketed AT33x cartridges. The three components are strategically arranged throughout the body of each cartridge to optimize sound quality and minimize parasitic vibrations.
The suspension is the cartridge mechanism that receives the vibrations produced by the cantilever, from the diamond traveling along the vinyl record groove. For its new AT33x series, Audio-Technica has chosen a slightly stiffer suspension than on previous models. The dynamic compliance is therefore slightly lower. Here, the Japanese brand’s intention is to provide greater adjustment flexibility for the cartridge and ensure compatibility with a wide variety of tonearms.
The cantilever of the 2025 AT33x series is made of Duralumin, a material harder than aluminum, machined into a cone shape and tapering towards the tip. The goal is to increase control of high frequencies during groove playback. On the flagship AT33xMLB model, the Microlinear diamond is installed at the end of a boron conical cantilever to deliver a rich and delicate sound result.
Audio-Technica has equipped the stereo cartridges of the 2025 AT33x series with dual moving coils with high channel separation. The AT33Mono cartridges are equipped with a True Mono coil, specially designed to capture only the vertical movement of the diamond on monophonic grooves.
As was already the case with previous AT33x references, the coil conductor is made of PCOCC (Pure Copper Ohno Continuous Casting) copper, known for being very pure. Ohno Continuous Casting is a Japanese copper casting technique developed by Professor Atsumi Ohno of Chiba University.
To make sound reproduction more dynamic and playback more detailed, Audio-Technica has opted for a neodymium magnet and a yoke (the piece that distributes the magnetic field around the space where the coils move) made of Permendur. This iron and cobalt alloy (in equal parts) supports strong magnetic fields and effectively guides magnetic flux. The cheaper AT33MONO/II is the only reference in the AT33x series to use a samarium-cobalt magnet and a pure iron yoke.
