Hardware Review by Jack Vanlieshout

I have been involved in Audio/Video for a long time, and of all the products involved in a system, speakers seem to be the hardest to get to know.

Speakers seem to be the component that is most affected by all of the other items in the sound reproduction line as well as the environment surrounding them.

Is the room dead enough or live enough? Are the walls solid enough, ceiling high enough? Are they toed in and leaned back correctly. Too much or too little and the sound can be changed dramatically.

That is just the speaker and room interaction. Now lets see if the cables are right and does the amp being used have enough guts to make the speaker work properly. Is there enough power there to push that woofer out, stop it and suck it back to where it started?
This is particularly true of larger speakers. Lets face, a speaker will, in its own time move back to its original position after it has been pushed out, but that is a slow process and would most probably sound about as crappy as can be. As such, your amp better be able to push woofer material out in a nano second and then suck it back to the position needed to play the noted requested completely against the wishes of nature and physics.

With the above in mind, I would like to attempt an amateurish description of a set of speakers that have found their way into my media room. The Definitive Technology Pro Tower 400's.
These rather odd looking speakers are about 4' tall 8" wide and less than a foot deep. They are somewhat squared off in front and very ovalized in the back. They are made out of a heavy man-made plastic or resin type material that seems very dead when I rap my knuckles on them. That is very good. They are designed to have spikes installed into the bottom thus coupling them directly to the floor rather than resting loosely on the carpet.
The speaker compliment inside of the so called "Box" are compromised of 3 - 6.5" woofers, 2 of which are used as a subwoofer, 1 of which is the midrange and a metal dome tweeter.
The woofers and tweeters are all placed into their own sub enclosures within the cabinet, which have been cross-braced considerably inside the cabinet. Again a very good thing. The 2 woofers that are used as a subwoofer are powered by an internal dedicated 125 watt amplifier whilst the other woofer and tweeter are powered by an external power source. Your amp or receiver.

I have always had some trouble with trying to match my previous ultra fast speakers to a subwoofer without some problems. Even when the speakers were rolled off properly and the sub came into play at just the right frequency, there were audible discrepancies. Lets face it, in general an 8" woofer moves faster and more easily than a 12" or 15" woofer does. As such there is quite often a speed and/or sound difference.

That is one of the reasons that I came to look into the Def Techs, the sub and mid range units were designed to work together from the get go.

And do you know what, they do work well.

I am still amazed at how some of the new speaker products on the market can get such amazing performance from such small enclosures and drivers. Take the Carver Sunfire True Sub for example. When that baby first came out it put out so much that it would vibrate across the floor. I was astounded.

Well here I am again. I cannot believe the amount of bottom end woof that emanates from the twin 6.5" "sub" woofers in each of the enclosures. In my somewhat largish room the bottom end is nothing sort of astounding. Tight, tuneful and DEEP. I would guess that they reach well into the lower 30 Hz range. With Authority. Physics be damned here my friends, these babies will move some air with speed and power.

Let us use a good example to start our demonstration, such as the beginning of Pink Floyds "Dark Side of The Moon". I prefer the 20th anniversary special edition. It is way smoother than the normal CD release with slightly wider dynamics and deeper more solid bass.

During the heartbeat section, the Def Techs can move the legs of my pants. The power and the glory that follows throughout the rest of the disc is there to be different drums used even when the bass line follows the drum whacks. This effect can be enjoyed at any reasonable sound pressure level…and beyond.

Guitars come across with a certain purity not always heard on speakers in this price range.

Cymbals are rendered with a certain purity while always maintaining that metallic sound. Instruments and voices are well preserved and do present a depth of image. Not as deep as my previous speakers but good nonetheless. Pretty Cool.
On orchestral pieces that require the reproduction of double basses and cellos they can really approximate the huge amount of air that comes from bows being pulled across the strings allowing the sound to resonate within the body of the instrument. Wood instruments sound like wood instead of bees flying in a group.
The Def Techs don't move as much air as an orchestra going full tilt boogie, but they can provide some visceral excitement that is heard at a live event. An example would be the ending of the Berlioz "Symphony Fantastique" on the Reference Recordings label. All of the music is there but I can hear the instrumental confusion setting in as the climatic ending approaches, the soundstage tends to fall in upon itself unlike the real thing wherein the music keeps swelling raising the flesh on my bones.

This may be a fault of the big Yamaha receiver; as such I hooked my audio only separates to these speakers to see what happens. The stand-alone preamp and power amp tend to have much more power reserve and as such they may be able to control the Def Techs during the big passages.

The extra power and control do help, but the music power factor is limited a bit. You can't defeat physics completely.

Lets move to the midrange, which is covered by what appears to be an identical 6.5" driver as the sub woofer section. It just operates in a different range. The midrange is smooth, dynamic and gives voices a nice feel. Guitars can really scream or be smooth depending on the source material. The dynamics here can be truly outstanding when called upon to do so. Just when you think that the speakers have reached an upper limit, something happens and they increase their power and volume another notch. These things can rattle the walls.

My one complaint is that these speakers don't seem to provide a certain lifelike quality I hear on some more expensive speakers.

But let us now get to what this page is all about, Home Theater.

I am using the 2 Def Tech Pro Tower 400's for the left front and right channels and the Def Tech CLR 1000 as the center channel. The CLR 1000 uses essentially the same dual woofers and tweeter found on the main arrays. I am using the center cannel mounted atop the 53" Sony RPTV and as such, the center channel is in a slightly different plane from the mains. Never the less the soundstage across the front is wonderful. There is very little timbre change when sounds pan across the front. Voices are well rendered and rarely sound boxy or nasal.

As with music, this system has dynamics that will rock your world. The speakers literally disappear within a huge sound field while all the while providing an incredibly lifelike reproduction of the action on the screen.

I took my normal subwoofer out of the system thus leaving only the Def Techs to provide the bottom end and all I can say is WOW!!

As mentioned above, the subwoofer section of these speakers move air. They can make the room quiver along with me.
It is not just the power of the bottom end that moves these things to a higher plane; it is the top to bottom cohesiveness that I really appreciate. When using a separate sub there is usually some disparity between the lower end of the mains and the upper end of the sub. Not to mention the fact that it is hard to match a sub to the mains sonically.

With the Def Techs there is no problems following a bass riff right on down the scale, top to bottom.

When viewing an action flick, the Def Techs never falter. They provide what is needed from Jet engines to thuds from a dinosaur foot. Something unusual is occurring here as well, take the new release of "Jaws" on DVD. Overall the sound is pretty unimpressive, BUT, there are times when a bullet is fired or the shark hits the boat that a huge visceral amount of sound pressure must be instantly emitted. These speakers do it with aplomb. Particularly the center channel.

Conversely take a Disc like "The Beach". I won't comment on the movie but the soundtrack is alive with things happening. From low-level bug noises to giant low frequency sounds. The Def Techs seem to take it all in stride and move along. I have found almost nothing that fazes these things.

I would highly recommend these speakers for movies, no question about it. They are wonderful indeed.

I am less enthusiastic about them for music, but only slightly though.

As I mentioned above they seem to lack some life that I find in more esoteric speakers such as the Magnepans (MY fav's for music reproduction) or Martin Logans. But then again, the Def Techs are cheaper and seem to perform better on movies than either of the above.

Try these for Home Theater you will not be disappointed.

Definitive Technology Pro-Tower 400



Cut Away

ProTower 400 Specifications: Dimensions: 38.5"H x 7.75"W x 11"D. Response: 19Hz-30kHz. Nominal Impedance: 4-8 ohms. Rec. Assoc. Amp: 20-250 watts. Driver Complement: Two 6.5" cast- basket subwoofer drivers,  one 6.5" cast-basket upper bass/midrange driver, 1" pure aluminum dome tweeter. Built-in Amplifier: 125 watts RMS with auto on/off. Finish: Black or White
Price: Black or White $549 ea.