Does Analog Summing Make a Difference?

Is there any Real Value in Summing Mixers ? What does Analog Summing mixer do?  Is it Necessary to have a Summing Mixer? How Important is Analog Summing?

You’ve probably asked yourself this question before; you’re not alone; thousands of others have asked it too

Short Version Answer: Simple Physics

The SUM BUS — Summing Mixer Input Resistor Network provides the SAFE ZONE called Headroom.

Headroom offers a secure space for your audio material. It preserves the separate focus of the instruments and maintains their proper position in the panorama field (Wide Deep 3D Sound). Through proper gain staging (sending a higher-level audio signal to the summing inputs and then hitting or getting the gentle analog harmonic distortion), you maintain and capture the fundamental harmonics in the SUM BUS, which are then summed to a master stereo track.

How does analog summing help you achieve a more professional sound for your music ?

1. In the analog summing mixer, your mix will never collapse. This is simple electrical physics; no magic is involved.
2. In the analog world there are no 0’s and 1’s, only voltages. In practice it is evident that your final MIX cannot collapse here, because there are no bits and bytes, no floating-point processor calculations, only voltage elements with rich harmonic transients.
3. The more channels you use in analog summing, such as 4, 8, 16, 32, or even 48 or 96, the more space and depth you get in your music. This makes your final mix sound wider and deeper in 3D, with improved instrument separation and high resolution.

Amplifying Harmonics: The VCA Amplifier Effect

Then pass them (main rec — record master stereo) through your DAW interface preamp or a transformer amp. Here, the (VCA) amplifier uplifts and boosts fundamental harmonics (which were created in the sum bus) and introduces additional excitement and saturation, enhancing the complex harmonics and creating the warm analog color character sound.

Main Rule: Analog Separation for 3D Sound

The more channels (4, 8, 16, 32, or even up to 48 or 96) you mix in analog summing, the greater the analog separation in the panorama field, creating a wider, deeper 3D sound.

Exploring Limitless Potential

Essentially, the analog summing potential is nearly limitless; it’s only limited by the number of output channels on your interface. If you’re interested in the extended version, I’ll try to outline the operation of an analog mixer as simply as possible. I know it has been easy for you so far because you’ve been mixing comfortably in the computer DAW — ITB (In The Box) with both its pros and cons.

Transitioning to the Analog World: A New Dimension

However, now, when you step into the real analog world, you’re entering a new dimension. To be successful, you have to understand how this works. Oh, and you need to learn some basic studio laws in theory and practice (I promise it will be simple, and you’ll have a good laugh once you understand how it works). Yes, you must practice to gain your practical experience.

Pro Techniques: Elevating Your Mix Like a Pro

If you simply send your mix through the summing mixer, your music will sound much better… But if you do it like a pro, you can get far superior results.

The Physics Behind Analog Summing

The answer is, it’s easy physics: since analog summing adds space for all harmonic elements, there are no digital 0s and 1s; no floating-point processor calculations — only voltages. 

While exporting the project into files (math summation), the digital system slightly rounds off values for level, pan, EQ-ing, and compression, resulting in a final mix collapse that is noticeably audible compared to the pre-export mix (I’m sure you’ve also experienced it).

Preserving Complex Sinusoidal Voltages

So, these complex sinusoidal voltages, comprising both harmonic and non-harmonic elements, including rich harmonics, transients, saturation, and other components, remain intact in their original form within the Analog Summing Mixer.

Sweet Spot: The Art of Subtle Harmonic Distortion

By boosting the input gain, subtle and pleasant analog harmonic distortion is introduced because the Analog Summing Headroom (due to its physics) provides space for transients and beneficial gentle harmonic distortion. 

This prevents collapse and delivers ‘pleasant harmonics,’ warmth, transparency, and more spatial depth. This is why your music sounds ‘like a record’; instruments sit better in their place when you run it through an analog summing mixer.

Maximizing Your Summing Mixer Potential

As mentioned, still you’re NOT maximizing the potential of your summing mixer; you’re only utilizing it at a basic level… 

You have to extract the best from your summing mixer, and you can only do that if you understand how it works. Imagine: I give you a tool. If you don’t know how to wield it, the results won’t be outstanding. However, if you learn to handle it at a professional level, you’ll create and achieve fantastic results.

Unveiling the Secrets: Crucial Aspects of Analog Mixing

Many music producers don’t know or don’t consider or ignore the base principles of analog mixing, even though it is very important and easy to understand. The following aspects are crucial in analog mixing to attain a genuinely unique and authentic Big Studio Analog Sound. I have many well-known big studios and Grammy-winning producer clients who use passive and active (or both) summing mixers with great success.

First Stage / Part 1: SUM BUS Analog Summing Inputs  –  Summing network  - Headroom  - Harmonic Distortion

This is essentially the mixer inputs, the part of the summing mixer where the input signals are directly connected, right after the interface outputs. It’s the post-input resistor network circuit, commonly known as the SUM BUS. It has been uniquely developed over the years, taking into account user feedback, to achieve uncompromised usability and configurability. It’s essentially manufactured to suit the user’s taste and studio setup DAW interface configuration.

Analog Headroom Protection: Ensuring Instrument Integrity

The SUM BUS — summing mixer input resistor network provides the SAFE ZONE called Headroom. The most important benefits under the protection of the Analog Headroom:

1. Maintain Instruments Integrity — Separation — in the panorama field
2. Preventing mix collapse, maintaining harmonics, transients, and saturation
3. Generate Fundamental Gentle Analog Harmonic Distortion
   Preventing mix collapse, maintaining harmonics, transients, and saturation

Analog Summing Versatility: No Input Limit

Facts: Analog summing has no input limit from a mixing perspective; it can easily sum together 8–16–32–64 up to 96 input channels. There are no floating-point mathematical processor calculations as seen in digital summing. 

When digitally printing to a file, certain parts of the mix or some instruments may become less distinct or muddy compared to the pre-export mix, in contrast to how the mix sounded before exporting.

Enhanced Separation for Depth: Channel Count Matters

The more channels (4, 8, 16, 32, or even up to 48 or 96) you mix in analog summing, the greater the analog separation in the panorama field, creating a wider, deeper 3D sound.

How to Attain Subtle Analog Harmonic Distortion in the Summing?

Once you’ve found the right placement — location for your instruments in the panorama field (where they sit better), you gently begin to increase step by step the volume of the main instruments or what you want to highlight — or make it more focused — is like pulling the focus of a camera lens (or on all tracks / increase the volume of the whole mix simultaneously) until you hear them filling the space (without overpowering the surrounding instruments). Finally, find the point where the harmonic distortion just begins or starts to come into existence.

Rule: Boosting DAW Output levels

Simply boost your DAW output level (master fader), and you’ll get some pleasant, gentle distortion as you drive the SUMMING INPUTS (SUM BUS) above its nominal level and find the “Sweet Spot.

Second Stage / Part 2: Boost / Attenuate / Amplify Harmonics -Gain Staging - Sweet Spot - after Sum Bus –  on master stereo out

Gain staging is the process of making sure the audio volume is set to an optimal level for the next processor in the chain (final DAW record or external process in outboard, EQ, Comp, etc.) You should find the maximum volume that your DAW interface or mic preamp input can handle without distortion, typically in increments of 0.1–0.2 dB, to get the best setting. The analogy applies here as well: it’s like pulling the focus of a camera lens. By proper gain staging through your analog and then your digital systems, you can achieve the best possible balanced and saturated sound for your recording.

How can I get it?

You can use your DAW interface’s Mic Preamp or transformer amp/amplifier to boost the signal on the summing outputs; you can also use your line-level inputs on your audio interface, your outboard preamps, or internal transformer amp (Active summing like Neumann), each providing a different color.

Amplifying Harmonics and Adding Excitement

With signal amplification, you achieve the following:

1. Harmonics amplification — amplifying the fundamental harmonics generated on passive summing (sum bus) inputs.
2. Excite and add harmonics — creating both even and odd harmonics using a transformer pre-amp or tube amp.

Pre-amp Plugin Emulations: Many of my clients have achieved excellent results with the well-known UAD Apollo Unison preamps. These pre-amp emulations have surprisingly delivered outstanding results, to the point where you can hardly tell on the first listen that it’s an emulation; it sounds soo good!