Review: Mäag Audio EQ4M Mastering EQ

EQ4M gains my highest recommendation. The highest? Yes—I bought one and the Universal Audio plug-in version, too.
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EQ4M gains my highest recommendation. The highest? Yes—I bought one and the Universal Audio plug-in version, too.

Cliff Mäag Sr. was way ahead of his time. When he created the NTI Nightpro EQ3 back in the early 90s, he implemented an “Air Band,” a high frequency shelving control placed very high—high enough to be beyond fundamentals, thus enhancing mostly harmonics and a sense of “open-airiness.” Four other well-placed, band-pass filters and a Sub band way down at 10 Hz allowed Nightpro some interesting mix/master sculpting possibilities—all with seemingly no phase shift or distortion. In 1997, the EQ3 became the EQ3D and earned a TEC Award nomination.

Fast-forward to today and Mäag’s legacy thrives, with Nightpro EQs still fetching top dollar and Mäag Audio (today involving Cliff Jr., brother Ryan and Travis Allen) churning out 500 Series versions of this legendary EQ. Now with the 19-inch rack mount version, the EQ4M, finicky mix and mastering engineers are given another useful airy option.

Just like the Nightpro EQ3, the EQ4M sports five fixed-frequency bands that are also fixed in bandwidth (wide). There’s Sub at 10 Hz, 40, 160, 650 and 2.5 kHz. Then there’s that iconic air band, switchable between 2.5, 5, 10, 15 (a newly added frequency), 20, and 40 kHz.

The EQ4M has added two volts of internal operating voltage thus more headroom, now +29 dB output is possible, and that is further enhanced by an input attenuator. True bypass, high input impedance, low output impedance and response out to 75 kHz (at only -2 dB!) ensure no-load, transparent, pro-level performance. See all the details here:

My recent purchase of a vintage Nightpro EQ3D and the subsequent serious improvements in my mixes had me in an excited tizzy to hear and evaluate the EQ4M. With my EQ3D I had noticed that very small changes in amplitude yielded the desired results; that larger changes remained musical (although personally I’ve never needed more than a couple of dB); and that this EQ affected tonal balance without affecting phase response, resulting in an overall “color-less” EQ rather than a euphonic personality box.

With my 2-mix routed from analog summing, to FET compressor, to EQ4M, to second compressor and then A-to-D conversion, I found the EQ4M to initially sound almost identical to my EQ3D with some notable operational differences. First of all (and purely skin deep), the EQ4M is attractive with a new shade of blue, all the familiar colored knobs and the umlaut (ä) within the Mäag name to serve as an LED “power on” indicator—all quite nice.

Frequent readers know of my preference for high operating voltages and these 18V rails deliver much more headroom; I was able to hit the EQ4M with about four more dB of input without clipping, making the input attenuator not as important as I thought it would be. Those that use lots more boost than I do will be glad for that attenuator, as it is truly clean. And as I dialed in EQ, the detented controls inspired more confidence in a perfect L-to-R balance, much more than the continuously variable controls of my EQ3D.

Any concerns about the EQ4M’s fixed frequencies are easily diminished once you begin to see how useful these frequency selections really are. For example, 10 Hz is quite useful (in small amounts of boost or cut) and the mid bands seemed to be placed for typical appropriateness (and do more heavy lifting than you might imagine for such wide Qs) but it’s the Air Band that brought me to the party. It can be placed very low at 2.5 kHz and at 10 kHz it sounds rather familiar. But at 15 kHz and 20 kHz the effect is unusual; it emphasizes and lifts the top end most transparently, and seems more psychoacoustic than obvious until I go too far, when it affects fundamental frequencies and I back off. Indeed, it is easy to go too far, but with moderation there is useful control for whole mixes, mastering and even some tracking and/or channel insertion for things like acoustic guitar, piano, vocals and strings where the openness sounds expensive and hi-fi.

Directly compared to my EQ3D I found the EQ4M air-band to be ever so slightly cleaner (and less apparent) in the upper registers, but with response nearly identical thru the lows and mids. Tonality may be basically the same, but the EQ4M has so much more headroom that it enabled me to run my signal path without any attenuation and the 15 kHz band became my new go-to frequency for sweetening the “tops” of mixes.

Astute readers know that Mäag is marketing these same circuits packaged in 500 Series modules—and for a substantially lower price (the EQ4M is $2,395 street while EQ4-500 Series modules are $850 each). I’m quite sure those 500 Series units sound great, and the plug-in surely does, too. But there’s something much more satisfying with the larger form factor, uncramped controls and the long-term investment benefits of the rack-mount EQ4M.

If you’d rather sand than chisel; if you prefer the less obvious results of linear phase EQ; or if you’d like to open up the top-end of your work then the EQ4M gains my highest recommendation. The highest? Yes—I bought one and the Universal Audio plug-in version, too.

Mäag Audio