Outboard

What are the different types of outboard gear?

Microphone Preamps
Microphone preamps increase the low-level signal coming from a microphone to a usable recording level. While every preamp performs this basic function, different designs can greatly affect tone. Transformer-based, tube, discrete, and ultra-clean preamps each bring something different to a recording, making the microphone preamp one of the most important choices in a signal chain.

Compressors and Limiters
Compressors and limiters control an audio signal's dynamic range and can be used during tracking, mixing, or mastering. Different designs, including FET, VCA, optical, tube, and diode bridge compressors, offer their own response and sonic character. From controlling vocal peaks to adding punch to drums or glue to a mix bus, hardware compression remains an essential studio tool.

Equalizers
Hardware equalizers let engineers shape a signal's frequency balance by boosting or cutting specific ranges. Some EQs are designed for surgical control, while others are prized for the musical color they impart even with minimal adjustment. Parametric, semi-parametric, graphic, and passive EQ designs can all play different roles in a studio.

Channel Strips
Channel strips combine multiple stages of a traditional console signal path into a single piece of outboard gear. Most include a microphone preamp, EQ, and compressor, while some add filters, gates, de-essers, or other processing. They can efficiently create a complete analog recording chain in one unit.

Effects and Signal Processors
Outboard effects processors include reverbs, delays, harmonic processors, saturators, de-essers, stereo image processors, and other creative tools. You can use these units subtly to polish a mix or more dramatically to shape the character of an individual track or complete production.

Mastering Processors
Mastering processors are designed for accurate control over a finished mix. These tools shape dynamics, equalization, stereo imaging, and overall level. From mastering-grade compressors and equalizers to limiters and specialized analog processors, these units help engineers make subtle adjustments that increase clarity, consistency, and translation across different playback platforms.

What form factors is outboard gear available in?

19-Inch Rackmount
19-inch rackmount gear is one of the most common formats for professional outboard equipment. These units fit standard studio racks and come in a range of sizes, most commonly 1U, 2U, or 3U. Rackmount gear can include preamps, compressors, EQs, channel strips, effects processors, and mastering equipment.

500 Series Modules
500 Series gear offers many of the same tools found in traditional 19-inch rackmount outboard gear in a compact modular format. A 500 Series chassis (also called a rack or lunchbox) can house microphone preamps, compressors, EQs, effects, and other processors from multiple manufacturers, making it easy to build a custom signal chain while saving rack space.

Desktop
Desktop outboard gear is designed to sit directly on a studio desk or workstation rather than inside a rack. These units are often compact and easy to access, making them a useful option for home studios, mobile setups, and engineers who want hands-on control without dedicated rack space.

Custom Rack
Some outboard gear, including vintage modules pulled from consoles or pieces built in unique sizes, can be housed in proprietary or custom racks with dedicated chassis and power supplies. These racks often allow multiple modules to be housed together and can offer unique routing, power, or integration options depending on the builder.