Review Velodyne Acoustics VI-Q 10:Features and technology
The common features with the Deep Waves models include, first of all, the consistent restriction to a single colour version, namely matt black. For ambitious home cineastes, no other colour is an option anyway, because glossy surfaces reflect the light from the projector and screen even in a darkened home cinema. Careful attention to detail is also evident in the robust, textile-covered cover frame, which is made of 10-millimetre-thick MDF: Instead of the magnetic fixation that is contemporary for loudspeakers, thick, solid retaining pins together with corresponding mounts on the baffle ensure that the cover does not vibrate at all, even at very high levels.
Connectors for all scenarios
In terms of connections, the VI-Q follows the company's credo of taking into account all application scenarios as well as the different equipment of the components to be connected. Therefore, the VI-Q 10, like all Velodyne woofers, has speaker-level inputs that allow the subwoofer to be connected to a stereo system whose amplifier has neither a subwoofer output nor a preamplifier output. In this version, one speaker cable leads from the amplifier outputs to the speakers as usual and another leads to the VI-Q's speaker-level inputs. Ideally, the stereo amp will have two pairs of outputs: otherwise, banana plugs or spade terminals and bare wire must be connected to the same binding posts, since the VI-Q - like almost all subwoofers - has no speaker-level outputs from which the second speaker cable would go to the speakers. Nevertheless, many discerning music listeners prefer this type of connection because the subwoofer receives the same, unaltered stereo signal as the speakers.
For stereo integrated amplifiers with preamplifier or subwoofer output, the VI-Q's high-level inputs, which are designed with solid RCA sockets, are recommended. The socket for the right channel also serves as an LFE input, which is the best choice for connection to AV receivers. To optimise the interaction with AV receivers, the VI-Q's internal DSP crossover can be deactivated with a small switch on its rear panel, with two LEDs indicating its status. This ensures that the AV receiver is allowed to do its job without interference when it comes to bass management. In a significant contrast to the Deep Waves models, the VI-Q subwoofers also have a second pair of high level inputs, fitted with XLR sockets. Balanced XLR sockets are particularly immune to interference, which can be quite relevant with long cable runs; many high-quality amps and AV preamplifiers are not equipped with these connections, originating from the professional sector, for nothing. In addition, the VI-Q also offers RCA and XLR high level outputs as well as an LFE output to pass the signal through to another subwoofer.
Technology
Closed cabinets are a Velodyne tradition, and the VI-Q 10 is no exception. This design principle has decisive advantages over vented enclosures when the primary requirement is to achieve maximum precision: Where there is no reflex port, there is guaranteed to be no airflow noise, and for the best possible impulse response, closed volumes are the silver bullet. However, they pose a challenge, because the forces acting inside the enclosure are enormous in a powerful subwoofer - a very rigid enclosure design is therefore a top priority. Thus, Velodyne manufactures the baffle of the VI-Q woofers from a high-strength, 50 millimetre thick multiplex board, which is made up of 21 layers. The remaining cabinet parts are made of HDF with a wall thickness of 22 millimetres. Robust aluminium feet connect the subwoofer to the floor; they are fully covered with synthetic fabric on their underside, which dampens vibrations and protects sensitive surfaces.
New cone driver
The components in the cabinet are also carefully designed and matched to achieve the most precise reproduction possible; with this in mind, Velodyne even does without the passive radiators implemented in the Deep Waves models and several other series in the VI-Q woofers.
The basket of the new 10" cone driver installed in the VI-Q 10 is made of steel to arm it against vibrations; the cone is made of carbon fibre and is therefore very light and at the same time particularly torsion-resistant. It is suspended in a wide nitrile rubber surround. The drive system has been optimised in detail to ensure the lowest possible distortion values. It contains a generously dimensioned ferrite magnet and has a 3" voice coil wound in four layers of pure copper wire. The voice coil former is made of double-coated carbon fibre, the large 6" spider is made of cotton-polypropylene blend. To minimise thermal and mechanical stress, six holes in the rear pole plate ventilate the drive system in the area below the spider, the pole plate in front and at the voice coil.
On the amplification side, the engineers rely on the proven Class D topology, powered by a fast switching power supply. Two MOSFET transistors in the supply circuit deliver 25 amps of current and 650 volts of voltage, ensuring superior power reserves.