ADC LM-100 MKIII ()
A well-tracked LP, a clean first note. A forgotten cartridge like this one could be behind it.
Overview
The ADC LM-100 MKIII is a phono cartridge from Audio Dynamics Corporation. The name never got the fame of Shure, Ortofon, or Denon. It's the kind of cartridge you'd find in a mid-tier turntable setup from the 1970s or '80s. Nothing flashy. Owners report a listening experience described as "superbly detailed, full-bodied, harmoniously excellent," with a particular strength in tracing record grooves accurately. That means fewer skips, less distortion, and more of what's actually in the groove.
It wasn't marketed as a flagship, and it wasn't entry-level either. It sat somewhere in the middle of ADC's lineup, though exactly where isn't documented. It offered a good balance for listeners who wanted better-than-stock performance without going into exotic (and expensive) moving-coil territory.
The stylus assembly is the part that stands out. This isn't a generic elliptical tip slapped onto a mass-produced body. The design focuses on precision, in both shape and material. That suggests ADC was aiming for clarity and tracking over sheer warmth or coloration.
Specifications
| Manufacturer | ADC (Audio Dynamics Corporation) |
| Product type | Phono cartridge (stylus/needle) |
| Stylus tip shape | Special elliptical diamond |
| Cantilever material | Thin-wall aluminum alloy |
Key Features
Precision-styled elliptical diamond
The "special elliptical diamond" tip implies a more refined profile than a standard elliptical stylus. It can make contact with more of the groove wall, especially in the high-frequency modulations where detail lives. This translates to improved high-end extension and reduced distortion during complex passages. The tip is also highly polished, which further reduces surface noise and wear on records.
Aluminum alloy cantilever
Bonded directly to that tip is a thin-wall aluminum alloy cantilever. It's lightweight and stiff, which helps keep signal integrity by minimizing resonance and energy loss between the stylus and the cartridge's generating system. Some high-end designs moved to boron or even beryllium. Aluminum alloy was a cost-effective middle ground, offering better performance than steel or plastic without the fragility or price tag of the exotic materials.
Integrated stylus-cartridge design
Internal construction details are absent from the record. But replacement styli are available (and sought after), which suggests the LM-100 MKIII uses a modular design where the stylus assembly can be swapped without replacing the entire cartridge. That extends the life of the cartridge body and lets users replace the wear-prone tip. It's a feature more common in ADC's higher-end models, so the LM-100 MKIII might have borrowed technology from above, even if the full specs remain undocumented.
Collectibility & Value
As of the latest data, a replacement stylus for the ADC LM-100 MKIII is listed at $53.95 USD. That's not cheap for a stylus-only replacement, but it reflects the specialized nature of the part and the dwindling supply. Genuine ADC replacement styli are reportedly hard to come by - "You're going to be hard pressed to find a genuine ADC replacement," one user noted.
The original cartridge itself doesn't appear frequently in collector circles, and no original pricing has been confirmed. Without production years or technical specs like output voltage or tracking force, it's difficult to assess its position in the vintage hierarchy. If the stylus wears out, replacements may be the bottleneck.
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