Manley Massive Passive Stereo Tube EQ
Manley have established a mighty reputation for their no-compromise outboard equipment. The attention to detail is astonishing, the manuals informative and entertaining, and the sound quality undeniably superb. So why the Massive Passive? Surely, the Pultec copy has been done-to-death? Well, the MP goes much further, with Pultec-derived technology pushed into new realms, as you will discover.
Like a Pultec, the EQ is achieved passively, i.e. with no amplification of frequencies as such, only subtractions, with an overall gain make-up circuit. Here, the four EQ bands are wired parallel, (unlike most EQs, which are series). This avoids extreme signal loss, so less gain (50dB) is required. Manley claim other benefits to this approach. In essence, it makes it difficult to overdo things, by virtue of the way the bands interact. Three bands boosting a similar frequency by 20dB will give a 20dB boost, not a 60dB one. (Who needs that?) Transformer-balanced outputs are claimed to also bring a sonic benefit.
Components have been carefully selected, and designed to interact musically, rather than achieving any artificial numerical goals in terms of bandwidths or dBs of boost. Rather than using a large bunch of transistors (like most EQs), the MP uses metal film resistors, film capacitors and hand-wound inductors to sculpt the sound. The restorative gain circuits use tube gain stages. There are two tube amplifiers per channel, and valves are run at over 300VDC. The output is capable of (cleanly) driving up to 37dBu!
The ‘Massivo’ lives up to its nickname. This 3U monster is extremely heavy. The thick metal front implies that this is not a box to be sniffed at. On the back, a big mains transformer is oddly mounted outside the case, no doubt for sonic reasons. XLR and TRS jack connections are all at +4dB, but the jacks can be made to work at –10dB by flipping internal DIP-switches. These are about the most modern thing inside, and looking through the mesh top is like peering into the back an ancient TV set.
The front panel has a smart, simple approach with the two channels' controls laid out side-by side with most of the controls mounted in black panels. The rest of the surface area is attractively etched metal. The larger panels are bolted-in modules which feature the controls and electronics of a single band, enabling possible future upgrades such as active bands, stepped-gain mastering EQ etc.
In the centre are main controls: Power is switched with a rotary knob. The illuminating ‘In’ button for each channel stays off for the first 20 seconds while the voltages build up to a relay click. The little Gain knobs for each channel are really just fine-trims, with a usefully high-resolution range of -5 to +4dB. High- and Low- Pass Filters are also positioned here in the middle. These each offer 5 frequencies (and Off) which are a sensible range of 22, 39, 68, 120 and 220Hz for High-Pass, and 6, 7.5, 9, 12 and 18kHz for Low-Pass. These are approximately 18dB per octave for the High Pass Filters, but somewhat steeper Low Pass Filters, with an especially steep 18kHz filter which is a remarkable 60dB per octave (theoretical) for "warming up digital". The lowest three Low-Pass filters have a little boost just below the cut-off frequency, which adds some colour, instead of just dullness.
Each band on each channel includes two panels of controls. The first, permanently fixed into the front panel, features a toggle switch for Boost, Cut (with LED indicators behind the legending) or Out, and a Shelf/Bell toggle. The former relates to the gain control in the other panel, and with only one direction to turn the knob, this gives double the range normally available on a rotary control. Therefore, 20dB of gain or cut is not unwieldy. These are stiffer and have a better feel than knobs on other Manley gear. There is little by way of calibrated legending, but this is deliberate, as with different settings there is between 6dB and 20dB maximum gain.
Switched frequencies are well-chosen, roughly º-octave spaced. These settings overlap and interleave, with the low band ranging from 22Hz to 1kHz , low-mid from 82Hz to 3.9kHz, high-mid from 220Hz to 10kHz , and high from 560Hz to 27kHz. As well as its conventional function in bell mode, the bandwidth knob also controls the steepness of the shelf. When in Shelf mode, setting a narrow bandwidth introduces what is referred to as a ‘Pultec Shelf’, i.e. the effect you get on a Pultec when you Boost and Cut a low frequency simultaneously. This gives a little dip in the low-mids above the main LF boost. With the Massivo you can also do this ‘upside-down’ using Cut, and the effect is pleasing with a High-Frequency shelf too. And all four bands have shelving capability. Marvellous! By the way, the two highest and lowest shelves behave differently from other frequencies, so as not to cause problems with extreme settings.
In use, one is sometimes surprised by the subtlety of extreme settings, and I found myself gratuitously EQing everything in sight as I recorded, often when I might not normally have EQ'd at all. Despite this perceived subtlety, the results were always far more satisfying than the 'flat' sound, and nothing like you would get from the conventional EQ on any console.
The manual is really quite remarkable in the depth of its approach, with an incredible detail of explanation into why the unit is the way it is. For example, the Power On switch warrants well over 200 words. Almost every design feature is justified, and any thoughts of criticism are headed-off with explanations. There is even a highly enjoyable section on studio engineering, which I suspect is more useful than certain audio engineering courses. The only pathetic 'moan' I can come up with is that the Bandwidth and Gain knobs feel a bit too loose. Either I am losing my touch, or this is the best outboard EQ I have encountered. The latter, I hope...
Reproduced with kind permission from www.George.Shilling.Com. Copyright ©