Individual licence: £63.99
Included in subscription plans from $149.99 / year
solidstatelogic.com
Name a classic expander. Go on, at least try. Can’t think of anything? No, neither can we offhand! While the recording world is overflowing with models and variations of compressor, and many of the most sought-after outboard units are compressors, their cousins, expanders, barely get a look-in.
Sure, there are fewer reasons to reach for an expander than a compressor. But if you use microphones and want to control the ever-present nuisances of mic bleed/spill and, in a live situation, feedback, then an effective expander should be an essential part of your signal chain.
What is this sorcery?
Originally a component of the SSL Live console range and now released as a standalone plugin, Sourcerer is designed for exactly these noise gating and feedback-stopping tasks. Although conceptually much the same as many other ‘downward’ expanders (an expander that kicks in when the signal falls below a set threshold), the thing that is immediately noticeable about Sourcerer is that it doesn’t look like most expanders.
Expander plugins typically present themselves as the opposite of a compressor, with similar parameter names and visualisations as found on compressors, but with everything working the other way around. Sourcerer, on the other hand, has been designed with its intended purpose front-and-centre, and it’s surprising how striking a difference this makes.
The primary controls for configuring Sourcerer’s expander have been reduced to just two dials, Threshold and Depth, along with three options – Fast, Med and Slow – for controlling the expander’s release speed. You are also given a choice of whether Sourcerer’s detector should operate in Peak or RMS mode, the former making it more sensitive to transients and rapid changes in signal level, and the latter smoothing-out those sudden changes.
When coupled with Sourcerer’s visual readout, these simple controls make light work of setting up the plugin on any source.
Intuitive visualisations
The visualisation features just two simple horizontal bar meters, the upper showing the input signal level along with a threshold marker, and the lower indicating the strength of processing being applied. Interpreting this readout proves to be remarkably intuitive. It’s obvious when the expander is ‘open’ and not affecting the signal, and it’s clear how strongly the signal is being affected at other times.
Additionally, alongside the Threshold dial is a lamp that lights when the signal is above the threshold, indicating that it is passing unhindered. This is, again, intuitive, although the lamp’s label of ‘Active’ is perhaps a misnomer given that the expansion process is inactive when the lamp is lit…
…or, more accurately, largely inactive, because Sourcerer has an extremely soft knee, and so its expansion ratio reduces smoothly and progressively the more the signal exceeds the threshold. This results in a forgiving, natural-sounding effect, with none of the ‘chopping’ of a more primitive noise gate, and little of the sudden volume drops that expanders can be prone to.
Sidechain filtering
The upper portion of Sourcerer’s window manages the sidechain, with a real-time spectrometer readout overlaid with markers for controlling the sidechain’s high- and low-pass filters. These make it easy to focus the expander’s sensitivity on a specific frequency range and/or have it reject frequencies that you aren’t interested in. For example, applied on the snare track of a multi-miked drum kit, Sourcerer’s sidechain filters can be used to make the plugin ignore kicks, hi-hats and cymbals whilst still responding faithfully to snare hits. Other expanders can do similar, of course, but Sourcerer makes easy work of setting this up.
The plugin also supports external sidechains, allowing one signal to be processed with the dynamics of another. When enabled, it’s this external signal that is shown in the sidechain spectrometer, making it easy to understand how the sidechain and main processed signal are interacting. There’s also a sidechain listen button, so you can hear what’s going on too.
Why’s there a ducker on my expander?
In addition to its primary expansion duties, Sourcerer also includes a Ducking section intended to help deal with inconsistent background noise/bleed being picked up by a mic. The ducker is relatively simple, with a dial to control the strength of ducking and a delay section for modifying the ducker’s timing with respect to the sidechain signal that’s triggering it, and its behaviour varies depending on whether that sidechain signal is internal or external.
When used with the internal sidechain, a DC offset is applied to the sidechain signal in order to increase the noise floor, thereby making the plugin respond smoothly and reliably to quieter noise. In our tests we find this to be only marginally useful because, in order to maintain Sourcerer’s otherwise perfect responsiveness, the ducking strength has to be so subtle as to be barely there.
Keying from an external sidechain to dip the signal’s volume in response to another is a more conventional usage of a ducker. In this mode, Sourcerer’s expander continues to key from the internal sidechain whilst the ducker listens to the external one. However, with only a single threshold setting shared between expander and ducker, this is rather awkward to configure.
SSL knows its business and so doubtless there are circumstances in which Sourcerer’s ducking stage is helpful. But, in contrast to the expander, we find it fiddly to configure and it does not add anything to the plugin’s core noise-gating role, or its feedback-reduction role. If we needed a ducker alongside Sourcerer we’d sooner set one up the conventional way using a compressor.
Should I buy SSL Sourcerer?
Ducking aside, and focusing on the plugin’s core purpose, there aren’t many expanders that deliver results that are as natural-sounding as Sourcerer, nor that go about their business with as much grace and effortlessness.
When working with full bands or other multi-miked sources, whether in the studio or on stage, the plugin makes it simple to isolate each sound source, cutting away the spill and crud to deliver a much more coherent, tight-sounding mix.
The plugin is great value too, being reasonably priced when bought as an individual licence, and bringing with it a huge library of high-quality SSL (and other) plugins if acquired as part of an SSL subscription package.
We’ll certainly be using Sourcerer as a go-to expander. We’re not so sure about the ducker though.
Key features
- Expander designed for controlling mic spill/bleed and feedback
- AAX, AU and VST3 (Apple Silicon native)
- Supports external sidechaining
- Ducking section
- Integrated help system
- Available as single licence or as part of subscription bundle
- Single licence price can be spread across multiple payments (rent-to-own)