Technical View - Satellites
The Z-5450 satellites are the first that we have tested to use a ported design, featuring a small port aprox 1" in size above the 2.5" phase plug equipped midbass driver. The enclosure sits on sturdy plastic stands angled slightly up towards the listeners ears finally cloth covered speaker grills complete the package.
Firstly upon initial inspection built quality appears solid with each speaker having a weighty feel which was a sign of things to come. Each speaker is equipped with an aluminum phase plug to help with heat dispersion around the voice coil - looks ace too! The rear of the units feature two spring loaded speaker terminals large enough for the included 16 gauge wire. It seems the inclusion of a dome tweeter is really something of personal choice by the manufacturer as there seems not to be any price consideration as these are Logitech's most expensive speaker system. The supplied cone is 2.5" in size and appears to be made of paper with a rubber surround. Paper is not the most durable material but is the best medium between price and longevity, and stamped boldly below is the THX symbol (more on this later) and Logitech's brand name. All very humble and solid to the touch, stands are non-adjustable but grills are removable. Power figures are as follows - front 38-watts, centre 42-watts, wireless surround 40.5-watts each, which should be more than adequate for a multitude of usages.
The supplied specifications rate the frequency response to be 35Hz - 20,000 KHz for the total system individual figures for the satellites were not readily available. Most systems of this size cross over between the sub/sats at around 150Hz, which is generally about the lower limit for 2.5-3" drivers. Unfortunately an inherent problem faced with using drivers of this size is the position of the sound stage, which is produced largely below waist level out of necessity for the small drivers. So now the responsibility of providing a full sound is thrown to the crossover (basically the circuitry responsible for separating frequencies) which needs to be sent to the subwoofer and the rest are sent to the satellites.
A common technique for blending sub and sat together is to set the subwoofer to produce frequencies up to and just above the lowest rated value for the satellite. This is to assume the driver in the satellite does not roll off completely smoothly and does dip in MAX SPL at the lowest regions of its response curve. So, a good designer will set the bass unit to just slightly over-run this dip and blend seamlessly together. However done too vigorously is to create a "bass hump", which is the ugly result of producing the same frequencies twice thus creating an imbalance in the response curve, which is perceived as loud disagreeable bass to the listener. Once a shoddy crossover is built into a system no amount of tweaking will ever fix it.
Wireless you ask? Well for all intents and purposes they are, as no cable needs running to the decoder unit or sub however two more power outlets must be found, in some cases it is probably a simpler task to just use the wired version which Logitech also sells. The Z-5450 satellites use Logitech's wireless technology which has enough range to cover most rooms and worked well for the most part without a hitch. The hitch being that a secondary TV set in my living room was noticeably affected with the use of these speakers close by. However, we think this maybe a fault with the shielding components in the TV as to a lesser extent the Megaworks produce a similar type of interference. On this alone we would not deduct marks for Logitech's wireless technology, as it is not conclusive. Overall though credit for offering a choice to the end user along with added flexibility.