ADC RSX-5 Stylus

A polished conical diamond for the ADC SX-5 cartridge. Clean, musical, and built to last.

Overview

The RSX-5 is the replacement stylus for the ADC SX-5 phono cartridge, also known as the SX5. It is the diamond-tipped part that goes in when the old one wears out. It is not a standalone cartridge and it is not an upgrade path. It is also the only part that touches your records. The stylus is a highly polished conical diamond. No line contact, no elliptical profile. It is plain workhorse gear meant to give reliable performance without costing much.

ADC doesn't make a fuss about this model in brochures or press releases, and you won't find it in vintage catalogs with any fanfare. It is a service part. Owners report it gives good rendition of voice and music, with precision tracing of the groove. That is a decent result for a conical tip, which typically gives up some high-frequency detail for durability. The polish on the diamond helps reduce surface noise, and the shape wears evenly across the groove walls, which is easier on your records over time. You don't think about it until it's gone, and then you're hunting eBay or specialty retailers.

Specifications

Manufacturer	ADC
Product type	Replacement stylus (needle) for a phono cartridge
Stylus tip shape	Conical diamond
Stylus tip finish	Highly polished
Compatible cartridge	ADC SX-5 (SX5) phono cartridge
Needle specification	0.7 mil Diamond conical tip needle
Tracking pressure	1,25 - 2,0 grams
Speed compatibility	16 or 33 or 45rpm NOT for 78rpm

Key Features

Conical diamond tip, 0.7 mil

The RSX-5 uses a 0.7 mil conical diamond stylus. That sounds modest next to modern elliptical or Shibata profiles, but it gets the job done. Conical tips are known for durability and for being forgiving on older or slightly warped records. They don't dig as deep into high-frequency modulations, so you won't get the same airiness or detail retrieval as a finer-profile needle. They do track reliably and are less likely to jump or mistrack. At 0.7 mil it is on the finer side for conical tips, which often run 0.6 to 1.0 mil.

Highly polished surface

The polish on the diamond is functional. A smooth, reflective surface reduces friction as the stylus rides through the groove, which means less wear on both the record and the stylus. It also helps minimize surface noise, so there are fewer pops and crackles. This matters most on records that have seen some playtime, where debris and groove wear make for a rougher ride.

Precision groove tracing

Despite its simple shape, the RSX-5 is described as offering precision tracing of the record groove. That is partly due to the consistent geometry of the conical tip and the rigidity of the diamond. It is also because the stylus is designed specifically for the SX-5 cartridge's suspension and cantilever system. It is not a universal fit. When aligned correctly and tracked within its 1.25 to 2.0 gram range, it keeps solid contact with the groove walls and turns the modulations into a clean audio signal without excessive distortion.

Compatibility with ADC SX-5 cartridge

The RSX-5 is made for the ADC SX-5 (or SX5) phono cartridge and nothing else. The SX-5 itself appears in ADC product listings and vintage archives, which suggests it had a run in the consumer or semi-pro market, likely during the 1970s or 1980s, though exact dates aren't confirmed. The replacement stylus ecosystem is still active today.

Collectibility & Value

The RSX-5 is not a collector's trophy, but it is a necessity for anyone keeping an SX-5 cartridge alive. As of current listings, a replacement RSX-5 stylus sells for $29.95 through specialty retailers like LP Gear. That is affordable by vintage audio standards, especially compared to rare cartridges or discontinued models.

Used examples occasionally surface on eBay, including listings described as “Used SX-5 SX5E 4120-D7 NOS NPS RSX5,” which suggests some buyers treat new old stock as a find. HifiShark.com also tracks used ADC SX5 phono cartridges. No common failures or maintenance quirks are documented, but as with any vintage stylus, alignment, tracking force, and cleanliness are critical. A misaligned RSX-5 will wear your records faster than it should.