The HAMMER nails it when it comes to stereo bus usage — "it adds punch, fullness and sparkle without adding any noise."
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I've been a huge fan of A-Designs since reviewing their MP-2 tube mic pre after it debuted several years ago. I went on to review their Pacifica mic pre (which I bought) and their REDDI tube DI. In each instance, I was impressed with the sonic and physical quality of A-Designs' product line.

Their latest device is the HM2EQ HAMMER, a dual mono-channel, three-band analog equalizer. The HAMMER has been engineered with a unique filtering system that allows the even harmonics to flow through its 12AT7 Philips tubes while filtering out unwanted noise. The result is a warm, musical sound with an open high end and amazing transparency for a tube device. The HAMMER provides a unique approach to equalization in comparison to other EQs; this quickly becomes apparent by looking over the filter-response graphs included in the owner's manual. Each of the HAMMER's three bell-curve filters span more than seven octaves at full boost or cut.


The 10-pound HAMMER is 10 inches deep and features beautifully milled aluminum knobs and a jet-black faceplate built into a 2U metal casing. The black faceplate is stunningly offset by the white titling, which makes for easy adjustment even in the dimmest control room.

Inside this hybrid vacuum-tube design piece is a toroid power transformer and a pair of 12AT7 tubes. The $2,695 box has a 30 kHz bandwidth and a -94 dBm noise floor. The frequency response -3 dB points are 5 Hz and 40 KHz. The unit is switchable between 120 and 230 VAC. The HAMMER's inputs are passive and each channel has a single 12AT7 tube in its audio path. (The noise floor is specified to be -94 dBm across a 30 kHz bandwidth.) The outputs are driven by ICs and are transformerless.

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The HAMMER's front panel has identical controls for left and right channels. The equalizer includes independent frequency selectors and gain controls for its low, mid, and high-frequency bands. Also included are a hard-wired channel bypass and separate high-cut and lowcut filter switches per channel. The filters' cut-off frequencies are fixed at 8 kHz and 84 Hz, respectively and their slope is 12 dB/octave. The low-frequency band is selectable between 30 Hz, 50 Hz, 100 Hz, 200 Hz, 300 Hz, and 400 Hz. The mid-frequency band is selectable between 250 Hz, 500 Hz, 1.2 kHz, 1.6 kHz and 2 kHz. And the high frequency is selectable between 2.5 kHz, 3.5 kHz, 5 kHz, 7.5 kHz, 10 kHz and 15 kHz. Each band's boost/cut control provides ±13 dB continuously variable adjustment with no detents. The control knobs are large and demonstrate smooth, deliberate motion. There are no Q controls, floating Q or individual band bypass switches.

The HAMMER's rear panel includes a pair of female XLR connectors for audio input and a pair of male XLR connectors for audio output.

In Use

I first put the HAMMER to use on kick and snare during a tracking session. I ran an AKG D112 through the Gordon mic pre then through the HAMMER on the kick and a Heil PR-20 thorough the Gordon pre then the HAMMER on the snare. I had good results in both instances, yet I occasionally missed the precision that I get when using an EQ with adjustable Q like the GML 8200. The bottom end sub-harmonic information I was able to pull out of the kick with the HAMMER was amazing. With a problematic snare drum I used the HAMMER to add some high-end sparkle and some punch with a single band of the GML set to a narrow Q to remove an annoying 800 Hz overtone.

During another tracking session I used the HAMMER on drum overheads, and again I had fantastic results. I used the Royer SF-12 through the A-Designs Pacifica mic pre and was able to get a beautiful sparkle and shimmer by boosting 10 kHz by 7.5 dB. In several instances (electric and acoustic guitar, violin, cello, and vocals), I found the HAMMER to be the perfect complement to ribbon microphones.

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While recording a Baldwin grand piano, I ran a spaced pair of Audix SCX-25 mics through a pair of Hardy mic pres and the HAMMER EQ and had fantastic results by boosting 50 Hz by 2 dB, cutting 250 Hz by 2 dB and boosting 15 kHz by 3 dB.

My favorite use for the HAMMER is strapping it across the stereo bus. Anyone who has complained about the sonics of mixing in the box should give the HAMMER a try as I've found it to completely transform my mixes into an entirely different beast; it adds punch, fullness, and sparkle without adding any noise. I've been using the HAMMER this way for nearly a year now, and I'm continually impressed with its detail and precision. Rather than add it toward the end of a mix, I'll add it early on before I start to insert a bunch of plug-ins on individual channels. This makes me rely less on plug-ins, which—when used overly aggressively—can often result in phase-correlation issues.

The thing that has continually amazed me about the HAMMER is that I can make drastic adjustments on individual instruments or on a stereo mix (boosting 10 kHz 9 dB, cutting 500 Hz 12 dB, or boosting 30 Hz 9 dB) and the audio remains smooth.

I wish that detented potentiometers on the band gain controls were optional; it would simplify recalls—but I'd be willing to pay more for this option. Additionally, I wish there was a way to bypass each of the three bands individually in addition to being able to bypass the entire EQ circuit.


The HAMMER is truly a new concept in equalization. This isn't the equalizer to tweak a narrow frequency band or with a vintage tube sound. But if you are in need of a broad-stroking, smooth, and sweet sound, the magical HAMMER could be your salvation.

Review Setup: Apple Macintosh 2 GHz Dual Processor G5 w/2 GB RAM, Digidesign Pro Tools 7.4, Lynx Aurora Converters, Lucid Gen-X-96 Clock, PMC AML-1 monitors, Focal Twin6 Be monitors

Russ Long is an producer/engineer in Nashville and a regular contributor to Pro Audio Review. www.russlong.ws