Smooth Operator Pro review: Baby Audio's latest game-changing plugin

Headliner gets an exclusive first look at Baby Audio’s brand-new Smooth Operator Pro - a supercharged follow-up to the manufacturer’s Smooth Operator plugin.

Baby Audio describes Smooth Operator as ‘a versatile audio plugin designed for both mixing and mastering’ - it serves as a channel strip effect that combines several essential processing tools: compression, EQ, and Saturation - with a slick and easy-to-use GUI in one interface.

It has been favoured for its ability to enhance the clarity and smoothness of tracks, making it a popular choice among producers and mixing engineers. 

While it’s always interesting to compare old with new, especially for those wanting to know about feature enhancements, the interface for Smooth Operator Pro looks so different, I’ll focus on the ins and outs from scratch.

Display

When you first open Smooth Operator Pro (SOP), you’re presented with a really cool-looking GUI. Front and centre is the main display screen, which gives you a real-time spectral representation of the audio coming into SOP, and above - but emanating from the top of this screen - a real-time representation of how the plugin is affecting the audio.

The screen is laid out as a graph with dB level on the right-hand side and frequency from left to right along the top. On the screen is a white line which represents the threshold of any processing together with a series of nodes (or pink dots!). 

Creating a node is a simple double click; how many nodes you can have isn’t entirely clear, but I gave up after quite a few and a very spotty pink screen - so plenty! Selecting any one of these will bring up information about each node in the boxes along the bottom of the screen.

Control

Top left sits the large threshold rotary, and turning it clockwise, you can immediately see and hear what this plugin does; and above the main screen is a handy selection box for the bank of available presets. Glancing through these presets, it’s pretty clear this is a plugin equally at home on a channel strip or a mastering bus.

Selecting a preset and editing is also a simple process: for example, let’s take the 'De-Ess Vocals’ preset that I jumped into: it’s a straightforward process to pick up the node that dips to 6.5kHz and simply drag the focus left or right to the frequency which best suits your vocal track. Really neat.

The left side controls are also rotary by nature; and at the bottom left side and below the centre section rotaries are six option buttons: Setup, Focus, Comp, Imaging, SC (side chain) and Output. 

While the threshold controls the position of the threshold line on the screen, manipulating any of the other controls on the left does not affect the threshold, but selecting any of these six lower options changes the available controls in the centre section.

For example, Setup provides three rotaries and one Even/Skew switch under the heading ‘Correction’. The rotaries are Lo Preserve, Hi Preserve, and Make-Up [gain]. When Skew is selected, the dynamic ratio of the threshold line’s curves are increased (or that’s what my ears are telling me, at least); and adjusting either Lo or Hi Preserve is not unlike bending the threshold up at either side to negate processing in these areas; but it’s more accurate and exact to use these controls in Setup.

Focus provides two rotaries and one Peak/RMS switch under the heading ‘Detection’. These rotaries are Detail and Isolation, which adjust the level of processing in and around individual instruments, reducing areas or resonant frequencies where multiple instruments clash. 

The processing here is often easier to see on the graph than it is to hear, depending on the quality of your monitoring, but if you’re in any doubt, grab a pair of decent headphones.

Comp brings up the three key rotaries of Ratio, Attack, and Release along with a knee select switch under the heading 'Comp Knee' which selects between Soft and Hard. No other explanation is needed here, as this is a fairly straightforward compression circuit emulation.

What is evident so far, though, is that each section affects the others and vice-versa, although collectively they let you know when you’re overstepping the mark, which is useful.

Imaging is also fairly obvious: two rotaries here, the first (left) is determined by the Mode switch between L/R and M/S (Mid/Side), which acts like a pan to focus processing in either direction: left to right or mid to side. 

The Stereo Link determines whether or not this occurs uniformly across both L/R, or whether they are treated as two separate channels - and likewise in M/S mode.

Side chain is just one control which adjusts the side chain gain, and via the switch, is either Off or On. The side chain’s audio source is selected from the Side Chain box at the top right of the GUI and shows all available audio channels from your project. This audio source then acts as the trigger for processing the audio track on which the plugin sits. Again, this opens a wealth of creative possibilities to the user.

Output is your monitor section and allows you to check your handiwork in real time. Move the Monitor switch from Output to ‘Removed’, and now you’re only hearing the audio that is being affected or reduced (processed) in some way. 

This is a feature that is synonymous with high-end plugins, and for less experienced users, it helps you to listen and hone in on the changes and tweaks you make.

Over on the right-hand side are a number of useful features like an A/B swap for comparison and an alternative view if you prefer entering values into boxes. 

There’s a small spanner icon which opens a settings menu giving access to a quick reset, Tooltips, and Theme, which changes the colour of the GUI between its three pastel shades of pink, green, and blue. There are also links to downloadable Shortcuts, Updates, and the Manual; as well as a really nice Suggest feature where you can contact Baby Audio with any ideas you may have to either improve, add to, or suggest for future plugins.

To the top left of the GUI is the usual On/Off button, a drop-down menu for storing and recalling presets specific to whichever DAW you prefer, and an undo history option. Below this are the Compare, Copy, Paste, Undo and Redo buttons.

Silky Smooth

It didn’t take me long to work my way around Smooth Operator Pro. Everything seemed intuitive and in the right place, which, as we all know, is super important when it comes to workflow and mastering one’s creative tools.

And as the name suggests, this really is a smooth piece of software. It effortlessly suppressed harshness and left both individual tracks and entire mixes free from muddy harmonic content. In fact, there were some mixes I wasn’t aware were at fault until I put this across the mix bus and heard the difference!

In some ways, it reminds me a little of oeksound’s Soothe 2 - but on steroids, almost, where everything is more obvious, instant, audible, and controllable. As far as multi-band channel EQ and dynamics for problem solving go, this plugin has got to be right up there.

What’s more, for an as-yet undisclosed limited period, we understand this will be available to new users for $79, and to existing Smooth Operator users for an upgrade fee of $29. That, in my opinion, makes this a complete no-brainer.