ADC SS-Two IC (1980–1989)
Twelve bands of analog EQ sculpting, wrapped in a no-nonsense black chassis that still lights up with VU meters like it’s 1983 and you’re fine-tuning a mix between sips of black coffee.
Overview
Plug it in, flip the switch, and the twin VU meters on the front panel twitch to life. That's the first thing you notice about the ADC SS-Two IC. It responds. It was built when American hi-fi companies were still chasing studio-grade performance for the home listener, and it isn't flashy. It's useful. Twelve sliders per channel each cover a fixed frequency band from 32Hz to 16kHz. That gives you fine control without over-correcting. This isn't a color box, it's a trim tool. Bypass it, though, and you notice it adds some presence even at flat - a slight lift in clarity and a tightening of the bass.
It arrived in 1980 as the evolved sibling of the original Sound Shaper Two. The "IC" suffix signals updated internal circuitry - presumably improved integrated circuits and better noise rejection. Many budget EQs of the time were thin-sounding and prone to hiss. The SS-Two IC had a signal-to-noise ratio that didn't embarrass itself, and distortion stayed under 0.02% THD and IM, which was more than respectable for a consumer-grade graphic equalizer. It wasn't marketed as a studio tool, but plenty ended up in semi-pro setups anyway, tucked between preamps and power amps in project studios where owners needed affordable tone shaping without sacrificing transparency.
The build is utilitarian: a steel chassis, rubber feet, and a black anodized aluminum faceplate with recessed sliders and big VU meters that track output level in real time. No backlit knobs, no blinking LEDs. It looks like something bolted into a broadcast rack, not perched on a walnut console next to a turntable. The RCA inputs and outputs fit into any stereo chain, and the front-panel bypass switch is mechanical - no relays to fail, just a clean hard disconnect. It runs on 120V AC, pulls about 18 watts, and doesn't generate much heat, which helps with long-term reliability. Inside, it's densely packed. Open the case and you'll find point-to-point wiring mixed with PCB-mounted components, a layout that makes repairs possible but not always fun.
Specifications
| Manufacturer | Audio Dynamics Corporation (ADC) |
| Production Years | 1980–1989 |
| Original Price | Not available |
| Equalization Bands | 12 bands per channel (stereo) |
| Frequency Response | 32Hz – 16kHz |
| THD | 0.02% |
| IM Distortion | 0.02% |
| S/N Ratio | Good (exact figure not specified) |
| Input Sensitivity | Not available |
| Output Level | Not available |
| Inputs | 2 x RCA (stereo L/R) |
| Outputs | 2 x RCA (stereo L/R) |
| Power Requirement | 120V, 60Hz |
| Power Consumption | 18W |
| Dimensions | Not available |
| Weight | Not available |
| Display | Twin VU meters (L/R) |
| Construction | Steel chassis, aluminum faceplate |
| Country of Manufacture | Taiwan |
| Special Features | Front-panel bypass switch, analog VU meters |
Key Features
Twelve-Band Precision with Real-Time Feedback
Most graphic EQs from this era gave you the sliders and left you to guess how much gain or cut you were applying. The SS-Two IC has dual VU meters calibrated to reflect output level, so you can see if boosting 250Hz is pushing your downstream amp into clipping. It's a small thing, but it changes how you use the unit. You end up watching the meters as much as the sliders, learning how certain adjustments affect headroom. And because the bands are evenly spaced on a logarithmic scale, you can make broad tonal shifts - taming a boomy room, lifting vocals out of a flat mix, or rolling off tape hiss at the top end - without the phase holes or comb filtering that cheaper EQs often suffer from.
Analog Integrity Over Hype
The SS-Two IC doesn't add color. Its circuit design prioritizes low distortion and wide bandwidth, so with all sliders at zero the signal passes through with minimal degradation. That's rare in consumer EQs of the period, many of which colored the sound even when bypassed. Owners report that after recapping and cleaning the controls (a common maintenance step), the unit performs as well today as it did in the 1980s. Deoxit on the sliders and input jacks is almost a rite of passage. Original pots can get scratchy, but they rarely fail completely. The power supply is simple and linear, with no switching regulators to wear out or fail.
Front-Panel Bypass and Build That Lasts
The mechanical bypass switch is one of the most underrated features. Units that use relays or electronic switching can be prone to failure or subtle signal degradation. The SS-Two IC disconnects the circuit entirely when bypassed, routing the input straight to the output via heavy-duty internal traces. So when you A/B, you're hearing a true comparison, not a signal still passing through op-amps or buffers. Add the all-metal construction and recessed controls, and this is a unit built to survive decades of use. It was clearly designed for places where reliability mattered - college radio stations, home studios, audiophile racks where gear gets used.
Historical Context
The early 1980s were a strange time for audio. CDs launched in 1982 and PCM recorders were creeping into studios, but analog was still king in the consumer space. Graphic equalizers, once the domain of live sound and broadcast, started appearing in high-end home systems as listeners tried to compensate for poor room acoustics or underperforming speakers. ADC, or Audio Dynamics Corporation, wasn't one of the big names like Pioneer or Sony. It carved out a niche with well-built, no-frills processors that offered pro-adjacent performance at attainable prices. The SS-Two IC was more capable than the five- or seven-band EQs bundled with receivers, but cheaper than studio-grade units from companies like API or Drawmer.
It competed with Radio Shack's Realistic line, the Fisher EQ-700, and the Sony EQ-3000, all of which had similar band counts but often used cheaper components and noisier circuits. The SS-Two IC did nothing radical. It did the basics exceptionally well, with no flashing lights or remote controls. It was built for people who wanted to fix a dip at 630Hz. Documentation shows ADC released several variants around the same time - the SS-1 with five bands, the SS-110 with ten - making the SS-Two IC the top-tier stereo model in their consumer lineup. The "IC" designation likely refers to internal circuit revisions that improved reliability and reduced crosstalk, though ADC never published detailed service notes.
Collectibility & Value
Today, the SS-Two IC trades in the $125-$250 range depending on condition, with fully serviced units at the higher end. Untested or non-working examples sell for as little as $60, often with listings admitting "power light comes on but right channel is dead" or "sliders are scratchy." These are usually fixable, but buyers should be cautious. The most common failure points are the slide potentiometers, which can develop noise after decades of dust and oxidation. Replacing them is possible but tedious - each slider is wired into a dense backplane, and sourcing exact replacements isn't easy. The power transformer is generally reliable, but electrolytic capacitors in the power supply should be replaced if the unit has been sitting for years. A recap typically costs $80-$120 at a reputable tech, and it's almost always worth it.
Working condition is everything. A half-dead unit can become a money pit. Look for listings that include close-up photos of the meters in operation and confirm that both channels respond equally. Also check the middle slider on the right side - if it's loose or wobbly, that's mechanical wear that could affect tracking. The chassis should be free of deep scratches or dents, though surface scuffs are expected and don't affect performance. It was made in Taiwan during a period of strong U.S. quality control, and surviving units tend to be well-constructed, though age has caught up with many. Those that have been maintained sound as clean and precise as they did 40 years ago.
As a tone-shaping tool in a vintage hi-fi chain, it's excellent, especially with older speakers that benefit from minor EQ tweaks. As a mastering-style processor, it's too broad for surgical work. It won't transform a bad recording, though it can make a good one breathe.
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