In-Line Mic Pre Buyers’ Guide

Over the years, the standard level of many professional standalone and console-based microphone preamps has topped at 55dB of gain an average. This level of gain is perfect for most phantom-powered condenser mics, externally powered tube mics, and dynamic and ribbon offerings—when used to record a loud source like drums or guitar cabinets.

However, that range can be a bit on the shy side when using (typically) low-output dynamic and passive ribbon mics. In these situations, pushing the preamp to maximum gain can induce added circuit noise and eliminate headroom. This is especially true with preamps built into many entry and mid-level audio interfaces.

While some preamp companies have risen to the challenge with +70dB input offerings, a common solution throughout the past decade is to use a phantom-powered inline preamp.

These devices, also called inline signal boosters, mic activators and more, are typically an XLR-based direct box or barrel-style device. They live between your mic and preamp and, through the use of phantom power, essentially turn any passive (ribbon or dynamic) mic into an active one with 10dB or more of extra input gain, depending on the chosen model.

In this buyers’ guide, we have rounded up 31 different models from 11 companies for you to check out. Some are simple, no-frills in-out boosters, while others offer added impedance selection, transformer-based coloration, alternate direct-box functionality, reamping and more.

As always, prices listed are street/MAP and subject to change.