I ordered the Logitech Z-906 to replace my long-lost Creative Gigaworks 7.1 THX kit (which, by the way, shook its own amplifier board apart), and am very impressed.
Packaging
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When the speakers arrived from Amazon, they were double-boxed: first in a stiff cardboard box for shipping, and inside that the thinner-gauge (but well-padded) Logitech box containing the kit itself.
A word of warning for those of you whom encounter the same confusion as I: the wires for three of the speakers (front-left, front-right, centre) are tucked inside a protrusion in the cardboard "netting" surrounding the speakers themselves. It took me a moment to figure this out as the rear-left and rear-right wires are visible with the speakers themselves, but the other three are concealed.
The subwoofer itself is self-explainitory, along with the AC cable, and a standard 3x 3.5mm 5.1 input cable for use with PC soundcards.
Inputs
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There are 6 distinct inputs provided by the Z-906: 1 of them is the 3x 3.5mm "analog" input, there are 2x Optical inputs, at least one SPDIF (Coaxial) input, and multiple twin-AUX (PHONO) inputs... all of which can be connected at the same time, and switched via both "head unit" as well as its remote control.
Remote Control
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The Z-906 comes with a neat remote control, small, with a total of 7 buttons: Power, Input Select, Mute, Level Select (independant volume control for each channel), Vol-, Vol+, and Effect (toggles between 2.1, 4.1 and 5.1 when not using DTS encoding from your audio device or PC).
The remote is (as one would expect) IR, so does require line-of-sight in order to function... though this is to be expected and works from at least as far away as 10 meters based on my own tests.
Surround Speakers
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The quality of the sound from the satelites (Front, Centre and Rear speakers) is exactly what you'd expect from THX-certified speakers... crystal clear, of very high fidelity, and free of the various types of distortion you get from lesser speakers.
Their construction has a very rugged and well-thought-out quality, and the single cone in each speaker encapsulates both the "Bass Reflex" and "Tweeter" along with the typical Mid-frequency you'd expect from a satelite speaker. This actually makes them look "cool", as well as sounding brilliant.
If you wish to modify the satelites (which I do NOT recommend... why mess with perfection?) you would need a 5mm Hex Key, as opposed to the typical Phillips Screwdriver you may expect.
The front and rear speakers can easily be mounted to stands (which is what I have done with mine)
Subwoofer
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The subwoofer on the Z-906 is very interesting, in that it is capped to remove distortion, which you may feel curbs some of the bass at the lowest end. This is actually a GOOD thing, as it addresses an issue I have encountered with a rival speaker system (Creative Gigaworks 7.1 THX) a few years ago where the vibration in the lowest end from the subwoofer literally shook the amplifier board to pieces, destroying the entire kit.
THERE IS PLENTY OF BASS provided by the Z-906! Far more than any sane person would ever want.
The build quality of the subwoofer box (which also encapsulates the amplifier and input panel) is the finest I have encountered for speakers of this type. The box contains a single Bass Port, which (despite what ametures may tell you) is far superior in quality and effect to having multiple Bass Ports.
The subwoofer cone is protected by a CONCAVE metal mesh, which is the first time I've ever encountered such a thing (all other subwoofers I've had have a CONVEX mesh, or no mesh at all). Making the mesh concave is actually very clever, as it prevents denting when moving and repositioning the Subwoofer. Denting would of course be a big problem as it runs the risk of puncturing the subwoofer cone as it vibrates... NOT a problem with the Z-906!
The Head Unit
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The Z-906' Head Unit is fairly attractive compared to others I have seen, with a sleek shape and the use of Orange LEDs (as opposed to the traditional Green).
The Head Unit provides 4 buttons (in order, Left to Right, same definitions as with the Remote): Input Select, Effect, Power, Level Select. Further-more, it provides a nice large dial (the Head Unit's counterpart for Vol- and Vol+ buttons as per the remote).
LEDs indicate the Power State, Input, Decode and Effect selections. A ring of LEDs indicates the volume level, where each LED has 3 levels of brightness as you increase or decrease the volume.
An arranged set of LEDs to the right provide indication of channels (e.g. they indicate when you're adjusting the volume of just the front speakers, or the subwoofer, or the centre channel, or the rear), and also show you whether your audio device (such as a PC or Hi-fi) is outputting in 2.1, 4.1 or 5.1 at any given time. This is a very neat feature, and the first time I've seen such a thing.
Recommendations
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I highly recommend running the Z-906 on an Optical cable if your audio device supports it! Failing that, use SPDIF (Coaxial) if available. Digital Input has superior transmission quality to Analog, and Optical in particular is 100% free of "noise" (which copper-based cabling is prone to).
Overall Impression
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The Z-906 is by far the best speaker system of its type I have encountered over the years. It is very simple to set up (shouldn't take you more than 10 minutes, most of which is the time it takes to unbox each item, and carefully lay down the cabling for each speaker).
It appears Logitech has applied focus to simplicity, keeping both the remote and the head unit free of "gimmicks" which could serve to confuse more than impress. This is a good thing, as you want Speakers to sound great (and good looks are a plus, certainly provided by the Z-906 in my opinion)... you don't want them to make cups of tea and toast! The Z-906 provides the raw ingredients for an epic surround sound (or even stereo, when playing music) experience.
The pricetag is good (especially when Amazon are selling it on offer) for a system of this calibre.
The RMS rating of the Z-906 is 500W total, however I have measured as high as 550W RMS, which (if you think about it) is more sound than you're paying for (a bonus).
This is a rare review for me, in that I have literally nothing negative to say about the Z-906 (so far, anyway). I was impressed before I even ordered them by their good looks and specification, I am pratically blown away by them as they sit here adourning my entertainment system.
Highly recommended for anyone serious about sound!