Royer Labs R-dB20 dBooster Class-A In-Line Microphone Signal Booster Royer Labs dBooster R-DB20 Manual

Royer Labs

Professional Audio Products

dBooster

In-Line Signal Booster

The Royer model R-DB20 is a phantom-powered ribbon and dynamic microphone signal booster
and impedance buffer. It offers a clean signal boost for passive low-output ribbon and dynamic
microphones. Designed for professional applications, the dBooster provides two levels of clean
gain boost; 12dB or 20dB, selectable by a front panel switch.

How to set up your dBooster

NOTE: It is a good idea to make all your connections before activating phantom power and
turning up your preamp level control!

The dBooster goes between any non-powered ribbon or dynamic microphone and your preamp,
DAW or audio interface. It will provide either 12dB or 20dB of signal boost for low output
microphones. A front panel switch establishes the gain setting. The microphone is connected to
the INPUT of the dBooster via a standard 3-conductor XLR microphone cable. The OUTPUT of
the unit is connected to any preamplifier, DAW or interface that is enabled with phantom power
capability.

The dBooster is a microphone level device and not intended to drive line-level inputs directly.
After your connections are made, apply phantom-power and slowly bring up the preamp level to
verify that the microphone is passing signal. To achieve the best performance from your
dBooster with minimal noise or distortion at the preamp, use the lowest gain setting that will
provide satisfactory results. The higher gain (20dB) setting is best for use with very low output
microphones, quiet signal sources or
low-gain preamplifiers.

Each application will vary based on the
mi cr o ph on e , si gn a l so ur c e an d
preamplifier, so feel free to experiment
and familiarize yourself with the
dBooster and its capabilities. If you
have any questions regarding the use of
this product you can always contact us
by visiting our website: royerlabs.com

Royer Labs 2711 Empire Ave. Burbank, CA 91504 www.royerlabs.com 818.847.0121

Circuit Description

The dBooster is an electronically sophisticated device. The dBooster design starts with a
differentially configured input stage consisting of multiple paralleled PNP semiconductors for
low noise performance. These semiconductors run in pure Class A for minimal distortion. The
preamp uses a current feedback mechanism and high-quality, thin-film resistors to further keep
noise and distortion low.

The output section utilizes a pair of operational amplifiers that act as buffers and low impedance
line-drivers. The output stage enables the dBooster to drive difficult loads without sacrificing
gain or performance while maintaining excellent headroom. Circuit power is derived from a
phantom-powered source and is fully regulated and de-coupled internally, providing clean
voltage and current for optimum circuit operation.

Warranty

The dBooster is covered by a one-year bumper to bumper warranty. This warranty covers parts
and labor but does not cover damage as a result of misuse or abuse.

This product was designed and assembled in the U.S.A. from components and materials sourced
globally.

Royer Labs

Burbank, CA

818.847.0121

royerlabs.com