Memphis Car Audio VIV900.5
Brand-new from the folks at Memphis Car Audio comes a line of DSP-powered amplifiers, with all-new looks and leading edge technology. The new series is known as the Six Five Series, and is Memphis' first real foray into the DSP world. There are seven different models in the series with one-, two-, four- and fivechannel variations.
All of the amplifiers have a cool new cosmetic treatment and have the controls hidden behind a magnetically-latched cover panel. For the purposes of this review, they sent us a pre-production prototype of the five-channel version, called the VIV (Six Five, get it?) 900.5.
The new look from Memphis also comes with a few unusual features, such as the ability to select from one of seven possible illumination colors for the power-on indication. The control for the LED color is found along with all of the rest of the controls, under the hinged front cover of the amplifier, just above the connections. In addition to the variable LED color, the amp is equipped with 24-dBper-octave crossovers, which provide bandpass configurations in addition to the typical high- and low-pass filters.
The VIV900.5 is rated at 50x4+300x1 into four ohms, or 75x4+500x1 at two ohms. Should the need arise, the sub channel can also drive a one-ohm load. Also, in the interest of maximizing system design flexibility and installation friendliness, the VIV900.5 has three different ways to turn it on, with sensing for DC offset as found on most head units, signal sensing with musical input, and the conventional 12-volt trigger. To make signal routing simpler for installers, there is also a switch that allows you to drive the amplifier with just a single pair of inputs, or four inputs to allow fading with constant bass output.
The heatsink is sized appropriately for this powerful an amplifier, and because of that and the high efficiency Class-D topology, the amplifier has excellent thermal performance, which is a sore spot for a lot of multi-channel car amps. The power and speaker connections will take generously sized cables (four- and 10-gauge, respectively) and the terminals are well-insulated and protected.
When it comes to tuning the system, to complement the accurate DSP-controlled crossover filters, there is also a variable bass boost controller that can provide up to 18-dB of bass boost at 45 Hz. This filter is also designed to have a high Q factor, which means its bandwidth is narrow so as to not have a detrimental effect on adjacent frequencies. This makes it more effective as a tuning tool, and results in a deeper, tighter bottom end.
I connected the amp in my sound room's reference system, using a two-ohm 12 in a sealed enclosure as my woofer system, and then two pairs of four-ohm component speakers were connected for the full-range sound. After setting the subwoofer crossover