CSS Model C4100 100W MOSFET Powered Mixer Amplifier – Made in USA Late 1970s–early 1980s

Estimated Year: Late 1970s–early 1980s

Made in: USA

Overview

The CSS Model C4100 is a vintage 4-channel powered mixer/amplifier designed for small PA systems, rehearsal spaces, and basic live sound applications. Built in the USA, this unit features a 100-watt MOSFET power section paired with a straightforward analog mixer layout, making it a reliable “plug-and-play” solution for vocals, instruments, or general audio reinforcement.

Each of the four channels includes mic inputs (XLR and 1/4"), individual level controls, bass and treble EQ, and reverb send. The master section adds global reverb control, monitor and main output levels, plus a built-in 5-band graphic EQ (80Hz, 250Hz, 800Hz, 2.5kHz, 8kHz) for shaping your overall sound. An FX loop and multiple output options give it extra flexibility for external processing or routing.

This style of powered mixer was widely used in small venues, churches, and practice setups—and today, it’s still a great budget-friendly solution or a cool lo-fi utility piece.

Features

- 100W MOSFET power amplifier

- 4 input channels (XLR + 1/4" mic inputs)

- Individual channel EQ (bass & treble) and reverb send

- Master reverb, monitor, and main volume controls

- Built-in 5-band graphic EQ

- FX loop (send/return)

- Main output and auxiliary/tape input

- Dual speaker outputs (A/B)

- Made in USA

Condition

Good vintage condition.

- Heavy cosmetic wear (tolex fuzzing, scratches, aging on panel)

- All knobs and sliders present

- Inputs and outputs intact

- Fully tested and functioning

Store Policies

- All items are tested before listing and again before shipping.

- Orders typically ship next business day.

- Shipping is available to the continental U.S. only.

- We do not accept trades on shipped items.

- Returns are accepted within 48 hours of delivery. The buyer covers return shipping, and a 20% restocking fee applies. If you have any questions before buying, feel free to message us—we’re happy to help.