Chasing Analog Character

I started in radio and at one point considered a career as a recording engineer. But the path took me to TV and then video post-production instead. I do mix simple projects as part of being a video editor, but complex mixes tend to go out to an experienced audio professional running Pro Tools. Nevertheless, I do keep my hand in mixing music just for fun. Thanks to the internet, even if you don’t know a band to record, you can download high-quality multitracks to mix. It’s a good way to improve your chops for other types of mixes.

I’ve paid close attention to the trends in audio plug-ins and some of the better YouTube channels related to audio topics. Naturally, the internet algorithms push more of this content my way. One trend in analog-style plug-ins for the past few years has been to emulate the channel strips of some of the top audio mixing consoles from past decades.

A trip down analog lane

Originally audio consoles for mixing were variations of radio broadcast consoles. Mono at first, since AM radio was mono, and later stereo. The typical AM radio console in the 1950s and 1960s was a unit that sat on the desk and featured rotary volume knobs, aka pots (potentiometers), for each input. Above the pot sat a switch for on/off, output, and cueing (audition a record without going out over the air). Inputs were set for various mics, turntables, tape decks, and cartridge players. The console’s signal passed through an outboard brick wall limiter and then on to the transmitter.

As recording technology became more “sophisticated” (think The Beatles), console designs changed. Rotary pots were turned sideways and adjusted with a lever-style volume control (fader). At most, each input might have basic filtering/EQ controls. Coincidentally, multi-track recording also came into its own, with recorders shifting from mono and stereo to 4 and 8-track configurations. Therefore, these consoles were designed to have direct outputs. Mic input 1 (fader 1) was sent out through the fader control directly to channel 1 of the recorder, mic 2 (fader 2) to channel 2, and so on. In the early days, having even an 8-track recorder was uncommon, so consoles were still relatively small. The classic example is the REDD console used by Abbey Road Studios.

As recorders advanced and track counts increased (16, 24, 32, and eventually synced 24-track machines for 48 tracks), so did the console sizes. Fader design also evolved to a flat slider, allowing for tighter spacing and more inputs. The mixing console sitting on the desk gave way to large mixing consoles that were the “desk.” While there were and are many different manufacturers, Neve, API (Automated Processes, Inc), and SSL (Solid State Logic) are ones that stand out. These were the consoles often used in studios where some of the iconic rock LPs of the 70s, 80s, and 90s were recorded.

Solid State Logic

The SSL 4000 E was introduced in 1979 as the first mixing desk with integrated dynamics processing on every channel. It also featured a master bus compressor in the center section. I’m familiar with the classic SSL 4000 E series desk, which was the Audio 1 mix console we installed in 1989 at Century III at Universal Studios Florida. The biggest characteristic of this mixing desk is the channel strip, which is what plug-in developers try to emulate today. The SSL 4000 E is quite possibly the most emulated channel strip plug-in of them all.

Vintage SSL analog consoles are still prized gear in many modern studios. The general signal flow of the console goes something like this. During live recording each input channel takes a mic feed, processes it, and sends it back out to the tape deck via a direct output. Then, in playback that same tape recorder channel feeds the line input of the same SSL channel for further processing. The mixed output passes through the center section of the console for the final stereo mix.

The key selling point was and is the integrated processing on each channel, including mic preamps, filters, gate/expander, EQ (equalizer), and compressor. A studio wouldn’t need to buy tons of outboard gear for EQ and compression, because most of what you needed was already in the console. In addition, classic SSL desks, like most mixing consoles, included a patch panel so that outboard gear could be patched and inserted into any of the channel strips. This is the origin for effects inserts common on the software mixer panels of most DAWs and NLEs.

More importantly for mixing engineers, all of the common processing controls are at your fingertips. No need to reach around to a rack to adjust an EQ or compressor, since you can dial in a knob right there on the strip. Only specialized items like a Lexicon reverb or Eventide Harmonizer require moving away from the desk.

Studios standardized on certain console brands, because of the sonic qualities characterized by the design of each manufacturer. To a critical ear, a Neve analog console sounds different than an SSL. Each has a different mojo, thanks to the electronics under the hood, curves selected for EQ and compression, and more. Aside from the physical layout of the strip itself, it’s this sonic mojo that developers like Waves are trying to emulate when they license and release a channel strip plug-in that models a classic brand and design. Even the original companies like SSL have their own flavor of these plug-ins.

Moving into the digital realm

Like all hardware manufacturers, modern SSL mixing products include digital, as well as hybrid console designs. The hybrid desks feature a combination of hardware surfaces and software effects processing. However, most users are running DAWs (digital audio workstation). These applications feature a user interface with mixing panels that mimic the fader array of a classic mix desk. But few include the full array of tools that a classic analog console offered as part of the built-in software channel strips. Apps like Logic Pro or Fairlight (within Resolve) do include in-line EQ and/or compression. But, the general approach has been to rely on native or third-party plug-ins inserted into the strip.

If you want a certain compressor, insert it into one of the available slots above the fader. Click the plug-in to open it and adjust the settings. Unfortunately, if you have both a third-party EQ and compressor applied, then you have to open two different plug-ins, many of which feature skeuomorphic designs to emulate the look of the real hardware – some larger, some smaller. Your screen starts to get rather cluttered, especially if you are doing this on several channels at the same time.

A new trend has been emerging, probably due in part to Universal Audio’s Luna DAW. This application is focused on mixing and takes more of an analog approach than other DAWs. Not only is the approach different, but it also strives to infuse the sonic qualities of analog gear. So now we are seeing a wide range of new third-party channel strip plug-ins, which each attempt to emulate the look and sound of the channel strip portions of classic analog mixing desks.

The truth about analog emulation

The color, warmth, or character associated with the analog sound is due to imperfections. An old chief engineer of mine referred to EQs, compressors, and similar devices as “controlled distortion devices.” Analog hardware uses components, like resistors and capacitors, which were and are all subject to a variance in tolerances, aging, and worse.

When a plug-in developer makes a licensed digital plug-in designed to emulate some piece of classic gear, they are often working from schematics of the design or maybe a working version of the actual piece of gear. However, if they are trying to emulate a console channel strip, odds are that they are modeling a single version or only a single input. In reality, the signal flowing through each channel of an SSL or Neve console is going to be slightly different from one to the next. That’s a result of the variances in the electronics for things like harmonic distortion, even though they may still be well within the design specs. Although extremely minor, channel 1 might sound different from channel 2 and so on.

Listen to experienced mixers talking about their favorite studios and you’ll quickly learn they always sent drums through specific channels, guitars through others, etc – simply because of these variances. If you loaded up Pro Tools with a Waves SSL 4000 E plug-in on each channel of a mix, it would not sound identical to a mix done on an actual SSL console. Furthermore, a vintage analog console today that’s in good condition has often been recapped – meaning, capacitors and other aged electronic parts have been replaced. This affects the sound. A mix on a vintage SSL today might also sound different than on that same console when it was new 30 years ago. A lot of this chase for the ideal analog sound is rather Quixotic.

To emulate these minor variations, Brainworx integrates TMT (Tolerance Modeling Technology) into their channel strip plug-ins (AMEX 9099, SSL 9000 J, Focusrite SC, SSL 4000 E). They have modeled 72 slight differences, intended to reproduce the channel-to-channel sonic variations of a real console. If you apply one of these channel strip plug-ins to multiple inputs, you can opt to set the TMT setting to all be the same number (1-72), be sequential, or be random.

When you click the TMT button to random, then each plug-in uses a different model from the 72 choices. You can opt to re-randomize the order and in doing so, get a slightly different sound to the mix. Do this a number of times until you get the magical combination that you like. While the differences may be trivial, I can attest that the changes are real. Of course, you are applying this to different sounding instruments in a mix anyway, so does it really matter? You decide.

Turning your DAW into an analog desk

We are so enamored with the analog sound, that this has taken many different turns. For  example, Pro Tools now includes a plug-in/feature called HEAT (Harmonically Enhanced Algorithm Technology). Quoting from the Avid website: “HEAT does more than just warm-up your sound – it actually fuses the color characteristics of vintage analog consoles, vacuum tube circuits, and analog tape into your mix using high-quality, sophisticated algorithms. In the analog world, euphonic characteristics are introduced across individual audio tracks when mixing on an analog console or tracking to analog tape. HEAT works similarly, processing all audio tracks individually. But it also gives you the power to tweak its Drive and Tone controls globally to get the sound you want, whether that means something richer, brighter, smoother, or livelier. You can also A/B individual tracks or the entire mix to compare your handiwork, choose a pre or post insert state, or bypass HEAT altogether.”

A similar approach using the channel strip interface is featured in the Waves CLA Mixhub. Noted recording engineer Chris Lord-Alge has partnered with Waves to produced a number of CLA-branded plugins. CLA Mixhub is his variation on an SSL-style channel strip. You can apply the plug-in to up to 64 tracks. By assigning channels to “buckets” – 8 channels per bucket, 8 buckets total – it enables you to work more like you would on a traditional console. Click an instance of the plug-in the single view and you see the traditional SSL-style adjustments: EQ, filters, dynamics, etc. Click to bucket view and you’ll see a group of eight inputs at a time. Now you can select between each of the sections. This enables you to work with eight EQs or eight compressors all at once, much like you would on a real console. To my knowledge, no other plug-in works this way… yet.

Of course, Waves is a popular plug-in developer and they offer many other choices for channel strips. One of my favorites is the Andrew Scheps Omni Channel. Scheps is also a top mixer who has lent his name to several plug-ins. Rather than do his version of an SSL or Neve channel strip, Scheps had Waves combine the tools he likes best, taking a little bit from a variety of analog tools. Not only does it include many useful tools in a single plug-in, but you can re-arrange the signal flow order. Want to swap the compressor before the EQ, or Gate before the de-esser? No problem. There’s also an insert slot to add in other available Waves plug-ins on your system.

I’ve spent a lot of this post talking about plug-ins that look, feel, and sound like vintage, analog hardware. Yet, there are modern approaches to a channel strip as well. iZotope’s Nectar, Neutron, and Ozone are exactly that. In the end, the appeal to a channel strip is ergonomics. All of the important processing is there close at hand without the need to open multiple plug-ins each with different interfaces. Not only should they sound great, but they should be easy to use and help you get to a great mix quickly.

As I’ve stated before, these plug-ins are all designed first and foremost for audio applications. Most will work within editing applications, too, although with some exceptions. Test a trial version before you commit. But, if you’re chasing an analog sound and mixing experience, many of these tools are worth your experimentation.

Addendum: During the last week of March, Waves abruptly changed its business policy from perpetual licensing to a pure subscription model. Later in the week they backtracked and announced that both perpetual and subscription options would be available after all. More on that in the next blog post.

©2023 Oliver Peters