10 EQ Modes Explained:  Clean or Colorful EQ

This may seem like a strange choice for a topic on EQ modes. Deciding on a Mode to work with regarding EQ is a decision of how the sound is being adjusted, what affect it will have in the entire range of Frequencies, whether the slope is steep or narrow, gradual or sharp, among many other factors. The design of the EQ itself is a major factor in how the EQ reacts, and though there are many EQ’s that share similar design and feature sets, the actual sonic results can be very different based solely on whether it leans more towards a clean or colorful electronic design. When these devices are emulated, their software equivalents will follow similar results.

A good example of how the electronic signal path affects how the same Mode settings are affected is the Millennia Media NSEQ-2 Twin Topology EQ. It allows the user to switch between the highest quality high voltage vacuum tube signal path or the highest quality op-amp solid state signal path that the electronics world has to offer. Using the exact same settings, the way that the Millennia Media NSEQ-2 renders the shape of the exact same setting in Solid State Mode is different than that of its identical setting in Vacuum Tube Mode. One will have a sharper result where the other will be slightly rounder. Both would be considered very precise, but that isn’t the only result. Both options are extremely clean, but the subtle harmonic content that is additive, and therefore measurable, has a definite final affect on the audio signal. In my opinion, the brilliant design seems to defy gravity and logic, in that there doesn’t seem to be a single setting that doesn’t improve the sound. But, it always seems to add something that is pleasant sounding and beneficial to the signal, yet it is so definitively “high end” sounding that you can use it for any mastering project in any music category and never feel that there was a better option. I feel this way about a few other EQ’s based on their own merits, but the NSEQ-2 definitely serves as the perfect example since it is the ideal in both solid state and vacuum tube Modes!

Cleaner EQ’s may follow a minimalist signal path with few capacitors, no transformers, and minimal wiring. The GML and Sontec are the most famous and ideal versions of this type of EQ. They have plenty of settings to choose from, and they can etch out the narrow troublesome tones or smooth out an entire range of Frequencies, but they do so with very little interference to any tonal aspect of the original signal. They are very clean, but they do not lack musicality. They measure very low in distortion and the timing elements are very accurate, yet still there is something sweetening and polishing about  their behavior. Even though they are designed for clarity and preciseness, even the manufacturers can describe the character as one device in their line and another as being more precise as another, or bolder in character and robust. Even in the “clean” camp there is a great deal of variety.

Program Equalizers are famous for using oversized transformers, hand-crafted inductors, multiple vacuum tubes, and larger-than-life power supplies. All of the items in their path are known to have a pleasant additive affect in the signal path, and yet they can be used on the most delicate of Program Material with absolute clarity and precision. It seems that even when there is a small measure of harmonic content and intentional heftiness in the signal chain, we can grab the subtle dynamic character of the source and somehow every detail can shine forth. Somehow, despite very low distortion, an incredibly low noise floor, precise timing elements and lack of phase shift, and an impressive flat Frequency response, we can hear the polish and silk and find it always a pleasant addition. Sometimes the benefits of clarity and color are intertwined and serve no reason or measurement for the reason they perform the way that they do. We can remove nearly all of this character and find the most perfectly clear and clean Mode EQ in digital form, with no aliasing, no distortion, no harmonic character, and a perfect precision. For the most part, this digital EQ might be capable of matching the exact same setting as a Sontec or GML or Pultec, and it will simply not sound good. Should we use it for mastering instead of the analog choice, even if there is some chance that there is some variation of imperfection that we are unable to measure? It is my opinion that we should always rely on our ears for the final verdict, and if this leads our choices to a preference over a measurement, then we can look at character as a choice in “Clean” and “Colorful” Modes regardless of the design.