They say they don't make 'em like they used to, but in the case of this Italian boutique filterbank, they do!
The Vertice Seconda Serie is an analogue 'filterbank' built as if it were 1975. I know this because creator Stefano Bersanetti sent me a foam board with a selection of the authentic '70s components he uses in every build, each one more chunky and colourful than the next. He is rightly proud of his through-hole and hand-soldered circuit boards, which are a work of art in themselves, and this passion for retro quality is evident in the front-panel design too, with chunky Bakelite knobs, switches which wouldn't look out of place on a submarine, chrome carry-handles, hand-crafted wooden end-cheeks and 'proper' quarter-inch jack sockets for inputs and outputs. Even the orange-on-brown panel printing will have you wondering if you've stepped back in time. The look and feel of the Vertice, then, promises something quite special in the sound department. Does it deliver?
In the best tradition of analogue filterbanks, the Vertice is built around three multi-mode 12dB/octave filters which can be arranged and modulated in different ways. The filter circuit is a customised Sallen-Key filter originally created by Nyle Steiner back in 1974, and most famously used in the Steiner-Parker Synthacon. It's a filter known for its lively, unstable resonance, and a fine choice for a 'character' unit. An interesting addition to the circuit design is a switch to change the resonance (referred to on the panel as 'emphasis', for purely historical reasons). The natural resonance of the Sallen-Key filter is Diode mode but there's also a Transistor mode here, switchable per filter. It's always difficult to describe resonance characteristics, but I think Transistor mode offers a meatier, more metallic body. Diode mode can be much more shrill, and disappears into ultra-sonic frequencies more easily. Both sound fantastic, especially when you overdrive the filter inputs.
Each filter has a set of controls at the top of the unit, comprising cutoff frequency, emphasis (resonance) and a low-, band- and high-pass switch. As well as each filter's frequency control, there's a large master control which offsets all three at once. The three filters can be configured using a series of switches to create serial, parallel or stereo routings, which appear at both a pair of...