UnicoDM is a hybrid dual-mono power amplifier design that is the perfect mate for the Unico PRE preamplifier, although it will blend seamlessly into most high-quality audio systems. Compared to the previous model of the same name, the new Unico DM features more than just a facelift. We wanted to substantially improve the unit in its most important design parameters, and the current version is more robust and powerful than ever before.
- Power output: 160W RMS continuous on 8ohm (stereo)
- 650W RMS continuous on 8ohm (mono)
- Frequency response: flat @ 10Hz ñ -0.1dB @ 100kHz
- Input stage: Pure class A Double tube stage (ECC82/12AU7)
- Output stage: Dynamic class A, Triple POWER MOSFET complementary pair
- Input connectors: 1 unbalanced, 1 balanced
- Output connectors: 4 + 4 per bi-wiring
- Power consumption: 900W max
- Dimensions: 17in x 7in x 17.3in
- Net weight: 55lbs
Unison Research really lives up to the name; it’s a true unison; a combination of loudspeaker manufacturer (Opera) along with two parallel electronics brands ? the all valve Unison and the valve/transistor hybrid Unico ranges. The Italian company has one of those richly deserved reputations for building lovely looking products, and even if the powder-coated Unison models represent the diffusion line, these aren’t exactly fugly products, either.
The looks are new, even if the names aren’t. There was a Unico preamplifier that came before, also called the Unico Pre. But that was big and tall and slightly clunky looking line-and-phono affair, where the new Pre just looks like a well-built, standard sized one-box line-only preamp. It’s a hybrid design, featuring J-FETs in the input stage and ECC82 double triodes in the gain stage. This, the company considers, gives the best overall balance; the J-FETs for linearity, the triodes for four-o (smooooth) smoothness across the mids.
It’s a four-input pre, marked CD, tuner and two auxiliary inputs. There’s also a tape monitor circuit. The inputs are run through both balanced and single-ended pathways, with a selector at the front. In theory, you could run four separate balanced and four single-ended sources (and the single-ended only tape) through the Pre. The chassis is laid out dual-mono style, with all the left and right channel inputs and outputs at either side of the pre, and the IEC mains and odd-ball spring-clip speaker cables-for-amplifier link in the centre of the rear panel. Each side of the Pre has one balanced and two single-ended connections to the power amp.
The DM power amp is also derived from its squared-off predecessor. It’s still a big case, but shorter and wider than before. The DM name is short for ‘Dual Mono’, and once again it’s two amplifiers in a box, sharing a common central power supply. The 150 watter is capable of being driven in bridged mode, at which point its power rises to a whopping 500 watts per channel. Like the Pre, the DM is a hybrid design, but this time uses a pair of ECC82s in the input stage (again, think smooth, this time just a three-o) and push-pull MOSFETS at the meaty end. It can be used in balanced and single-ended mode.
Aside from the more conventional lines, the biggest changes to the amps involve increased logic control, especially on the Pre. Both models still have soft-starts and carefully controlled warm-ups (no sound for the first 30 seconds to give those tubes a gentle nudge into life), but now without the pink light show from the power button. In addition, the Pre now moves source selection from a simple four-position rotary dial to a logic-driven affair. This means little green indicator LEDs at each source and a central LED volume display. It also means the control surfaces have some of the worst feeling knobs around, completely free from resistance and with some deliberate play. This isn’t a deal-breaker, as it’s a sign of moving away from ‘hard’ controls on the front panel, but some still want their volume dials to feel ‘right’ and that’s not going to happen here. The remote, on the other hand, feels wonderful thanks to its wooden back panel. Unison alternates between handsets with the bare minimum of buttons and ones that can control anything in a 20 metre radius. This falls into the latter category ? given the limited level of control on the front panels, this handset can operate balance, control matching CD players and more. Comprehensive, but you might spend a lot of time swearing at it because the pause button looks identical to the station selection control.