ADC XLM Improved MKII

Name: ADC Improved
Brand: ADC

The ADC XLM Improved MKII is the cartridge people chase when they want tight bass and a wide soundstage from vinyl.

Overview

Old-school analog people still say "ADC XLM Improved MKII" like a secret handshake. It's a moving magnet cartridge that went head-to-head with the Shure V15 Type III, not just kept up with it. Audio Dynamics Corporation built it, and it made its name in the late '70s and early '80s as a high-compliance, low-mass design with a spacious, dynamic sound. It wasn't cheap. It cost $100 in 1980, a full 25% more than the Shure M91ED, and the people who bought it weren't shopping on price alone.

Owners report a balance of warmth and precision: bass that's tight without being lean, mids that breathe, and highs that shimmer without etch. It was made for tonearms that can handle high compliance, like the SME Series III or the Infinity Black Widow, where its 65 x 10⁻⁶ cm/dyne compliance works as intended. It didn't have the replaceable stylus modules of the V15. The "Improved" designation marked an upgrade in suspension and tracking over earlier XLM models.

The XLM Improved MKII wasn't a mass-market player, but it was respected. The Boston Audio Society tested the 1975 XLM II and found it quieter than the Shure V15 Type III. That wasn't the Improved MKII specifically, but it points to the engineering behind the line. Buyers wanted engagement, texture, and a sense that the music was happening in the room.

Specifications

Manufacturer	ADC (Audio Dynamics Corporation)
Technology	Induced Magnet
Product type	Moving Magnet (MM) Phono Cartridge
Tracking force range	0.75 - 1.5 g
Output voltage	5.5 mV per cm/S
Compliance	65 x 10^-6 cm/Dyne
Stylus tip shape	Nude Elliptical Diamond
Stylus tip dimensions	0.0003 x 0.0007 inch (0.3 x 0.7 mil)
Cantilever	Thin-wall alloy tube
Frequency response	10Hz - 20kHz ±1dB, 20kHz - 24kHz ±1.5dB
Channel separation	28 dB at 1kHz, 18 dB at 10kHz
Inductance	580 μH (1kHz)
Resistance	820 Ohms
Recommended load resistance	47,000 Ohms
Recommended load capacitance	275 pF
Weight	5.75 g
Output balance	1.5 dB max. difference

Key Features

Patented Low-Mass Induced Magnet Design

ADC engineered around the competition instead of cloning it. The XLM Improved MKII uses a patented induced magnet system that keeps moving mass very low, which helps tracking and transient response. Some moving magnets feel sluggish in the upper mids. This one stays nimble, and the speed and clarity feel more "moving coil" than MM. The 580 μH inductance sits in a good spot for standard MM inputs, especially with the recommended 275 pF loading.

Improved Suspension System

The "Improved" in the name isn't marketing fluff. It refers to a real upgrade in the suspension, which improved tracking stability and reduced resonance problems in earlier versions. Combined with the 65 x 10⁻⁶ cm/dyne compliance, the cartridge could ride the groove without bottoming out, even on warped pressings. That high compliance needs a tonearm that can handle it. Pair it with a low-mass arm and it sings. Put it on something too stiff and you lose the magic.

Nude Elliptical Stylus on a Thin-Wall Alloy Cantilever

The stylus is a nude elliptical diamond with 0.3 x 0.7 mil tip dimensions. It's small enough to dig deep into the groove and traces both vertical and lateral modulations with confidence. "Nude" means the diamond is mounted directly to the cantilever without a metal shank, which cuts mass and improves high-frequency response. The thin-wall alloy tube cantilever trims weight further while keeping rigidity. Users have praised the "bass/mids/treble/detail/texture/smoothness" balance, and this construction is a big reason for it.

Headshell-Ready Body with Threaded Mounting

The cartridge body has threaded holes for direct headshell attachment - no screws through the top, no wobble. It's a small thing, but it shows in the build quality. At 5.75 grams, it's light enough for high-compliance arms and still feels solid. There's no fancy housing or exotic materials, just a clean, functional design.

Historical Context

The ADC XLM Improved MKII lived in the shadow of the Shure V15 series. It was positioned as a direct competitor to the V15 Type III, with similar performance and a different engineering approach. Shure leaned on replaceable styli and mass-market reliability, while ADC focused on low-mass precision and compliance. In 1980 it carried a $100 price tag, 25% more than the Shure M91ED, which suggests it was aimed at serious listeners willing to pay for refinement. The earlier XLM II, tested in 1975 by the Boston Audio Society, was found to be quieter than the V15 Type III, which likely paved the way for the Improved version. The "Improved" designation marked a generational update across the XLM line, including the XLM I, II, III, and Integra, with better suspension and tracking for those who wanted to upgrade without replacing the entire cartridge body.

Collectibility & Value

The ADC XLM Improved MKII is long discontinued, and finding one in good condition takes patience. The biggest hurdle is the stylus. A new genuine replacement runs between $150 and $208, with one listing spotted at €85 in April 2025. That's still a steep cost for a single part. Used cartridges with the original stylus are a better value, though prices vary widely: listings show used units with stylus from $128.99 to a previous asking price of $324.99, with a typical market range now around $175 to $244. The cartridge body alone trades between $80 and $230. That might make sense if you're pairing it with a new stylus, but given the cost, it's rarely a bargain.

Stylus replacement is expensive, and there's no user-serviceable module. Alignment and tracking force need precision. The Improved MKII is no longer in production, so there's no guarantee of future support. Collectors value it not as a daily driver but as a period-correct high-end piece for systems that can do it justice. It's not the easiest cartridge to live with.