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Logitech Z-640 Review

Logitech Z-640
MSRP $43.00
“Overall the Z-640 is one of the best systems in the sub $100 price range; high praise for such a competitive market.”
  • Great value
  • excellent bass and treble
  • The mid range is lacking


With ever increasing applications for speakers (new game, computer, & theater systems) as well as new standards (5.1, 6.1, Dolby, THX, etc.) audio makers are constantly aiming at a moving target.  The latest two releases from Logitech (Z-640 & Z-680) aim to fill all the home needs at two very competitive price points – and do very nicely.  But after last year’s award winning Z-560 series that may come as no surprise.   Read on to see how the Z-640 compliments Logitech’s speaker line-up.


Logitech currently offers a fairly wide range of speaker choices at very competitive price breaks.  The Z-640 Dolby digital 5.1 surround sound speakers list for ~$100 but can currently be found online and with various rebates for less than $60.  There are presently more than a dozen manufactures of PC speakers in this price range so it does well to note first the features that set these apart from the rest.

First and foremost the quality and volume of the bass are outstanding – the best we have found in this price range.  The subwoofer alone uses 23.5 Watts RMS – almost half of the 6-speaker system’s combined 51 Watt power.  (As a side note we are pleased that Logitech sticks to the more accurate RMS rating than the oft exaggerated peak-power that nearly every other speaker manufacture in this price range does.)  Even at maximum power we detected very little distortion from the sub – which is exceptional in this price range.  The hefty sub is enclosed in a sturdy non-ported enclosure that is also remarkably good looking.   The built-in amplifier and all the speaker connections live in the back of the sub, making it heavier than it would seem.  These help to keep it from bouncing around when the bass hits.  The bass volume control is also on the back of the sub – perhaps not the best place but nevertheless the standard.

The four satellites and center channel speakers each use 5.5 Watt 1 7/8″ tweeters that produce adequate highs and almost work as a midrange.  If it wasn’t for the lackluster midrange capability we would have given the Z-640 a perfect score.  (Note that the two more expensive Logitech models use a bigger tweeter with excellent midrange)  Yet at this price range it is hard to find much better in all-around sound.  (i.e. Several similar priced speakers have better midrange but worse high and lows.)  Mounting is quite simple with a reversible stand on each unit, allowing the satellites to mount on either a horizontal surface (shelf, floor, etc.) or a vertical surface (wall, side of TV, etc.) and still point horizontally.   The center channel has the volume, fader, center, and matrix controls, as well as a headphone jack.  More expensive models more conveniently place these controls in a separate box, allowing adjustments without reaching over the screen to the center channel speaker.

For what it is worth, the Logitech system is arguably the most aesthetically pleasing speaker system among similar priced units.  In particular the blue LED power indicator in the center channel is eye catching (especially for infants).

Perhaps the best feature of the speaker system besides its price is its versatility.  Not only can it be used with 5.1 Dolby digital capable PC soundcards, but an included adapter allows any device with stereo RCA audio cables to be connected & played on all speakers by simply pressing the matrix button.  This allows PC, video game systems, TV, VCR, and DVD to all use the same speaker set.  Probably the most un-advertised and most useful application is that it makes a very capable and cost effective home theater 5.1 Dolby digital surround sound system.

Setup and Installation

Setup is quite simple as the satellites each use a cable with one RCA connector to plug into the sub.  More expensive models use standard speaker wire and work better for custom installations where custom lengths are needed.  The Z-640’s RCA cables could be extended by buying extra male to female RCA cables.  This would be needed for a full installation but for a computer desk with relatively short distances to the speakers the included cabling is adequate.


Logitech has done an excellent job with its latest Z-640 series speakers and, because of the price, we have found little to criticize.  Bass and treble frequencies are excellent, midrange frequencies are slightly lacking.  Logitech’s two more expensive models provide better midrange but for a cost.  Overall the Z-640 is one of the best systems in the sub $100 price range; high praise for such a competitive market.

Editors' Recommendations

Digital Trends Staff
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