Roger Schult had a very interesting idea. His mastering equalizer, the UF1, which he calls an Aural Editing System for Mastering Environment, has been getting rave reviews from the few people lucky enough to get their hands on one. However, at a price point of €10,399 EUR, it's a little tough for many people to afford. In order to give his designs a little more breadth, he decided to package the filters individually as 500- series modules. The complete W2377 system is essentially an API 6-space lunchbox with two high-frequency modules, two mid, and two low. With a little patching, you have one of the most delicate 3-band stereo equalizers I've ever heard.

At first, while using the system as a mix-bus EQ on a new White Bike Soundsystem track, I found the setup a bit awkward. I'm not a fan of unnecessary cable runs, and even with short cables, there was about 2 ft of slack between each filter. It wasn't until I took it off the full mix and separated the channels out to the patchbay that I started to have some fun with the design. My initial impressions were not very exciting. I leaned on the mid band pretty hard trying to dig some aggression out of a guitar, and no matter how much I turned it up, the sound remained pretty smooth. Then I remembered that these filters were designed as mastering EQs and focused on using the low band to add a more subtle body to the kick drum. Subtle is not something that I think most people would say about my mixes, but the more I altered my behavior to work within the constraints of the EQ, the better my mix started to sound. The stepped Q controls really helped me accent the ridiculous low-end extension of the drum without mucking up the rest of the mix.

Another feature of the individual modules is that each one can be used as a band-pass, high-pass, or low-pass filter. If there's one thing I love having around, it's high and low pass filters. The mid-band modules, which didn't get too much of a workout during the session, ended up as extremely cool high- pass filters for the guitars, with a ton of control.

Being unable to resist taking a peek inside I pulled one of the low channels out and was surprised by what I saw. There appears to be almost nothing inside of them! No big transformers, no complicated op amps - just an extremely short signal path running on totally normal integrated circuits. I reached out to Roger to ask how he'd gotten such an amazingly clear and focused sounding equalizer circuit out of the most common IC in the audio world. His response was that the design is a state-variable filter, which is a parallel design in nature. What this means is that when turning the gain knob, you are in fact adjusting the mix between the clean signal and the equalized signal, leaving what remains of the original signal intact without any of the side effects associated with amplifier circuits. Then he went on to describe to me the process of selecting the ICs themselves. Each one is tested thoroughly, with only a few living up to Roger's standards. Then all of the surrounding support circuitry is tested to be within 0.5% of the necessary values, and the board itself is poured through in order to determine the way the signal traces are affecting each other, something I've never heard anyone but microphone builders speak of doing due to the extremely high impedances found in mic circuits. Each unit is tweaked by hand to a degree of precision that can only be explained by listening to the filters themselves.

In order to make sure that this EQ got a thorough review, I decided to do something I normally would not - master a record. It was an album by me and my close friend Charlie Hoey under the moniker Housewives and Hard Drives. I'm very vocal about the fact that I am not a mastering engineer, and hence do not take on mastering work. I prefer to leave it for the many ME's I know who are extremely talented, but since it's my own record, and there's no budget, I figured I'd give it a shot. The chain I used was the W2377 into an ADL 670 (Tape Op #35), followed by a Gyraf Gyratec XIV EQ, just in case the W2377 wasn't giving me something I felt I needed. I quickly realized this wasn't going to happen and pulled the Gyraf out of the chain.

Once I was focusing on making more delicate moves, the W2377 really began to shine. Slight controlled boosts in the high end gave me the brightness I needed without stretching too far towards boosting the sibilance, which I had left quite a bit of during the mixing process. I felt like I could reach into places in the mix I normally couldn't get at and make those slight adjustments that make the difference between a track sounding balanced and a track sounding great. It was a bit like using a robotic arm for surgery; I had the confidence and the control to reach in places that would normally feel risky and manipulate things that would normally be too small to perceive. The filters are still made up of Frequency, Gain, and Q controls like any other EQ, but something between the clarity of the filters themselves and the fantastic pacing of the controls (the knobs themselves are some of the best I've ever felt) makes the unit feel far more precise. Also, each module has a button labeled Focus which inverts the filter. When trying to clean up a track, you can press Focus to quickly hear a cut as a boost, making it far easier to locate troublesome frequencies.

In addition to all of this, the modules are connected via jumpers on their front panels. The square plastic jumpers are a bussing system which makes it possible to solo individual filters. While I found these functions at least somewhat useful, this is the point where the 500-series aspect of the design began to feel a little gimmicky. If the modules are all going to be bussed together, why not just put them in a rack unit and give the filters individual inputs and outputs? But after spending some time with the unit, I've answered my own question. If I were mastering full time, the whole EQ would be a standout piece, and certainly a contender for even the most high-end signal chain. In my own position tracking and mixing, the whole unit would be overkill, and outside of my budget for a stereo EQ. However due to the modular design, I can keep just what I need, which will certainly be at least one of the low-frequency bands. The W2377 is a scalpel where I would normally use a machete, and having one or two of the filters around would be more than enough for my purposes.

With this EQ, Roger Schult has built something that brings the level of quality involved in designing and building a top- of-the-line Aural Editing System into the hands of tracking and mix engineers, as well as mastering engineers who already have a workflow that they're happy with but could use just one or two extra bands. It's an interesting tool, and one that I'm hoping to spend more time with. ($895 per module;,

-Marc Alan Goodman, 

Tape Op is a bi-monthly magazine devoted to the art of record making.

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