Such is his perfectionism, Douglas Fearn spent nearly 10 years researching and designing this stereo compressor. You’ve seen the picture, it’s a 3U case, but in the flesh it is an even more imposing construction, with a great thick bevelled-edged front panel, and a paintjob seemingly thicker and more shiny than a brand new steam train.
The unit is extremely heavy, approaching 10kg, and the case is very deep. Despite an all-valve Class A signal path, a surprising quantity of solid state electronics governs the compression characteristics. The case packs in circuitry of all types, from hand-wired components to surface-mount chips. Although I did not experience excessive heat it is recommended to allow 1U of space above and below. Furthermore, there is a side-mounted fan, which was a little noisier than I was comfortable with, with the unit unracked. But this was Serial No. 006, which had evidently been bashed around a bit. Under the thick steel top panel there is an internally mounted thick steel sheet holding an entire city of components, including five PCBs, eight valves and four Jensen transformers, two labelled as custom made for Fearn.
One PCB includes large capacitors resembling an oil depot. The other boards are stacked in pairs, and include surface mounted components. Several larger items hide underneath the metal sheet, including the mains transformer and aforementioned cooling fan. Eight separate regulated voltages are supplied to the plates. The inner workings of this lovingly assembled monster are quite something to behold. Controls are in mirror formation on each side of the front panel, these correspond to left and right channels. Great big toggles switch the VUs from gain reduction to level indication, and these are proper official VU meters – their characteristics conform to the relevant ASA standard, despite the cute stylised vintage surrounds. These are pleasantly rear-lit, and there is also an orange ‘pilot-light’ when power is on. To be picky, orange legending on a red background doesn’t make for the most legible of labelling. And the mirror layout of the knobs is counter-intuitive, so I was frequently turning the wrong knob! However, none of the knobs are labelled with any calibration, so this is really a suck-it-and-see unit, where the use of ears come first and foremost.
The rear of the deep, thickly panelled case includes XLR connections for the inputs and outputs, an IEC mains socket and voltage selector, plus a ground binding post. Also found hidden here beneath the IEC socket is a power rocker switch – not the most convenient location on a deep rack-mounting unit.
After ditching the LA-2A concept, Fearn chose an unusual approach to compression. According to the manual, using a very high frequency carrier signal, a pulse-width modulator controls the duty cycle of a gain reduction element. Despite the solid state boards witnessed under the lid, the signal does not itself pass through this complex gain control, but instead a shunt circuit controls gain reduction, thus avoiding degradation and distortion. So this is no Fairchild – the sound is incredibly clean, quiet and neutral for a valve compressor, and relatively transparent. However, despite the transparent nature, it sounds big and natural, effortlessly controlling signal dynamics. There is no discernable colouration, even when working fast and hard. And it can certainly do that – the time constants range from extremely fast to very slow.
The uncalibrated pots work smoothly, although the rotary Separate/Linked switch had worked itself loose on the review model. The Threshold knob reveals a fairly hard knee as it is turned clockwise. There are conventional Attack and Release knobs, but rather than a ratio control, there is a Harder-Softer knob. This control is difficult to fathom at first. Often, it seems moderate changes to this have little sonic effect, mainly because the compression is so clean. But this adjusts several characteristics; at Harder, the ratio is increased, but also, fast attack and release times seem to get even faster, so that large amounts of gain reduction on the fastest settings can start to introduce break-up of the sound on, say drums. With a fast attack, it is possible to make drums sound choked. Slowing the attack and keeping the Release fairly quick produces great crunchy drum ambience, but this breathes better with the knob at full Softness. Turn towards Harder for more constipation.
With all settings there seems to be something of an automatic release occurring, with fast transients flipping back and longer notes keeping the needle down for a very slow recovery when they stop. Due to this clever circuitry, it is difficult to overdo other instruments and particularly vocals. Harder is generally better for tightening up bottom end, bass guitar is tamed in a very natural way with no apparent choking, although Softer can be more exciting, allowing more freedom for the signal to breathe. Because of the interaction with the Attack and Release knobs, it is best to tweak all three when setting up. The make-up Gain controls range from around -3 to +15dB, a good range with plenty of gain available, and allowing fine adjustment. In Linked mode, all the control is on the left channel, with the right’s Gain knob the only active knob on that channel. This makes stereo setup very straightforwards.
The VT-7 represents one very dedicated man’s vision of the ultimate compressor. And that vision is that it should essentially be invisible. It doesn’t shout and boast, but instead performs an honest job of keeping dynamics in check. It is very hard to make this unit do anything bad; even if you set everything as fast as possible, the distortion is far from nasty. For all the solid state electrickery, you get a big natural valve sound, and even the hardest compression won’t colour the sound. You really can’t go wrong.
Straightforward, honest, intelligent, clean, valve compression; almost never sounds bad; compression can be virtually inaudible
No bypass; no sidechain input; fan noise; rear power switch; mirror layout not intuitive; poor legending; heavy; expensive; compression can be virtually inaudible
Reproduced with kind permission from George Shilling. Copyright George Shilling.