ADC RSQ-36

A well-cut elliptical diamond can make the vocals sound like they're breathing, once the groove locks in.

Overview

The ADC RSQ-36 is a stylus, the needle that rides the record's groove. It was made to replace the original tip on an ADC cartridge, and there isn't much documentation on which one. As of the last known listing from LP Gear, it's discontinued and no longer available. It doesn't have a spec sheet that runs three pages, but a lot rides on a sliver of diamond and a hair-thin cantilever.

ADC was a name that carried weight in the moving magnet and moving coil world during the analog heyday. The RSQ-36 was designed as a precision replacement stylus. Its job is to translate microscopic groove modulations into electrical signal with as little compromise as possible. There are no production years, no original pricing, and no confirmation of which cartridge it belonged to. The available description points to a performance-minded upgrade path for someone who already owned the right ADC cartridge and wanted to keep it going, not a budget refresh.

The LP Gear listing makes clear this wasn't a generic re-tip. The description emphasizes "very accurate playback of recorded voice, music and harmonics," which suggests it was tuned for fidelity over warmth or coloration.

Specifications

Manufacturer	ADC
Product type	Stylus (needle)
Stylus tip shape	special elliptical
Stylus tip dimensions	.0003 x .0007 inch
Cantilever material	Custom alloy
Cantilever description	Thin-wall alloy cantilever
Stylus diamond	highly polished
Construction	diamond tip titanium bonded to the cantilever

Key Features

Special elliptical diamond tip

The RSQ-36 uses a "special elliptical" diamond tip, so it isn't a generic elliptical profile. The word "special" hints at a more refined radius or polishing technique, likely meant to improve high-frequency tracing and reduce inner-groove distortion. At .0003 x .0007 inch, the tip is narrow enough to track fine modulations without excessive wear. The diamond is described as highly polished. That matters, because microscopic roughness on the tip can abrade the groove over time.

Thin-wall alloy cantilever

The RSQ-36 is mounted to a custom alloy cantilever with a thin-wall design, which favors rigidity and low mass. A lighter cantilever can respond faster to groove walls, which means better transient response and less inertia-induced distortion. The custom alloy, rather than standard aluminum, suggests ADC was tuning for specific resonant characteristics, though without original cartridge specs that is only an inference. The diamond tip is titanium-bonded to the cantilever, a technique that improves mechanical coupling and reduces energy loss at the joint.

Performance claims

LP Gear's description calls out "excellent tracing of record grooves" and "very accurate playback." It also notes that the replacement version features "a better diamond tip and sound accuracy tantamount to its improved performance." That implies the RSQ-36 wasn't a like-for-like swap but a refinement, possibly even an upgrade over the original.

Collectibility & Value

As of the last available listing, the ADC RSQ-36 is discontinued and no longer available through LP Gear, so it now lives in the used market or on repair benches. The last known retail price was $69.95, which for a single stylus sits in the mid-to-upper tier of replacement pricing. There's no data on common failures, maintenance needs, or user impressions. It's not a display piece and not a grail, just a functional component for someone maintaining a specific ADC cartridge setup.

Similar items on eBay

No exact ADC RSQ-36 listings are live right now — these searches show current ADC and similar vintage audio gear on eBay:

Search ADC RSQ-36 on eBay Browse ADC audio gear on eBay

As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.