Miniature Loudspeaker



Single-driver advantages
Plug and play solution with Outline L3000 power amplifier
Excellent spoken word intelligibility
Fitted with M4 and M6 installation points and included bracket
HCDF (Hydrophobic Compact Density Fiber) ensuring toughest places operation Applications
Applications: Lounge Bar / Restaurant, Museums, Conference, Discrete installations


A tiny box full of useful

Created by Outline’s engineering team to solve the problem of delivering rich, natural audio from the smallest possible footprint, Charlie 4 re-writes the rules on what’s possible from a loudspeaker that fits in the palm of your hand. Despite its diminutive size and weight, this loudspeaker produces rich, highly intelligible audio (whether pre-recorded or from a live source) and is powerful enough to deliver it across a surprisingly wide area.

Charlie 4’s key design features, mechanical characteristics and performance parameters include:

A Big Heart In A Small Body

Charlie 4 features a brand new 4” cone transducer, created by Outline’s engineers just for this product, this 100% Italian-made unit is super-efficient and applies the same top-class audio engineering found in our larger transducers to a unit a fraction of their size.

Single-Driver Advantages

Single-driver designs enjoy a major sonic advantage in that they do not suffer from the phase anomalies caused by a crossover and so produce the most natural and uncoloured sound. Outline’s engineers have extended this advantage by creating a new design of membrane which dramatically improves the off-axis performance, a key feature for ultra-compact, multi-application loudspeaker systems.

Designed For Professional Power Amplifiers

The new 4” transducer is designed to be powered by professional power amplifiers and its output is simply prodigious, producing power and reliability that belies its size. Contained within an enclosure measuring just 12cm x 12cm x 12.6cm and weighing only 1.55 Kg, Outline’s world-class audio engineering has produced a robust and reliable integrated design which punches far above its weight in terms of audio performance and service life.

Design That Is Pure Outline

A striking design feature of Charlie 4 is the pair of O-rings at the front and rear of the unit. Not just aesthetically pleasing, these components also assist with vibration-damping and also stabilise and protect the enclosure from irregular surfaces.

Simple Mounting And Location

Every Charlie 4 includes a multi-adaptable mounting bracket, again designed specifically for this product. A pair of M6 bolts locate through the bracket and into threaded inserts in the loudspeaker, while the adjustment range and shape of the bracket allow it to be mounted securely on virtually any surface.

Processing And Power

Outline’s ground-breaking L3000 power amplifier is the ideal partner for Charlie 4. Its flexibility, power and onboard DSP are all contained within its surprisingly modest size. Alternatively, any of Outline’s amplifiers will work just as well and the iP24 processor is the perfect external processing partner.


Frequency Response (-10 dB) 110 Hz – 17 kHz
Nominal Dispersion Axisymmetric 60°
Impedance (Nom / Min) 16 Ω / 12.7 Ω
Watt AES (Continuous / Peak) 70 / 280 W
Maximum SPL Output * 118 dB SPL
* calculated using +12 dB Crest Factor signal (AES2-2012), Half space


Component 4″ High Power & Dispersion Fullrange Driver
Connector 4-pin Euroblock
Cabinet Material HCDF (Hydrophobic Compact Density Fiber)
Cabinet Finish Black or White textured polyurethane paint (overpainted RAL colors on request)
Grill Epoxy powder coated
Installation points 2 x M6 + 3 x M4 on the rear panel + 1 x M10 on bracket
Height 120 mm – 4 6/8”
Width 120 mm – 4 6/8”
Depth 126 mm – 5”
Weight 1.55 kg – 3.4 lb


Architechtural Series Brochure

Oct 2020

CHARLIE 4 Architectural Specifications

Sep 2021

CHARLIE 4 User Manual

Sep 2019

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