The Speaker as a System
The ingredients of a speaker function as a system only if great care is taken in the matching of the individual components and dimensioning of the cabinet to match the crucial driver (woofer) parameters. With German engineering and ingenuity the L700A (and L500A) accomplish in modest sized enclosures what other manufacturers often do less well in "battleship cabinets". You will be amazed by the clean, accurate bass performance of these speakers which employ very modest sized drivers (7" diameter for the L700A; 8-1/2" diameter for L500A). It is not true that low frequency bass means large woofers, our 7" woofers work very well at 25 Hz. But it is true that in two-way speakers, small sized woofers yield superior dispersion in the midrange. Also the musically important transient response of a small woofer excels. That's why we choose small woofers for the benefit of open, transparent reproduction without compromising bass performance.
The L700A (and L500A) are designed to reproduce the input signal as faithfully as possible. Both offer very smooth full-range frequency response from the lowest organ tone to well beyond audibility, superb dispersion and unsurpassed transient response.
The Woofer
The L700A is two-way acoustic suspension speakers. Truly good-two-way systems are difficult to design since woofer and tweeter have to cover a rather wide range of frequencies. For instance, the Braun woofer does cover a large portion of the midrange frequencies, up to 1500 Hz. The human ear is extremely sensitive to coloration and distortion at these frequencies, therefore our engineers developed a unique woofer cone material, which is stiff so it moves like a piston at bass frequencies, yet is soft and self-damping at high frequencies to prevent cone break -up . In addition, this material had to be light so that musical transients would be quickly and cleanly handled.
Our woofer cone has a soft suspension resulting in a low resonant frequency and making it move with high efficiency and accuracy.
We believe it should not require a super-power amplifier to drive our speakers to high levels properly, so we built the efficiency into our drivers. We gave them unusually strong magnetic fields (9500 Gauss). In this way even a fairly low power receiver driving Braun speakers will give you concert hall realism. Efficiency is a particularly important consideration in four-channel installations, since quadrophonic receivers often offer less reserve power per channel than stereo receivers. Of course the Braun works well with high power amplifiers also.
The Tweeter
All Braun loudspeakers from the smallest to the mighty three-channel LV 1020 share one jewel, the unequalled 1" diameter soft-dome tweeter. This elegantly simple-looking device gives Braun speakers their unprecedented open clarity, superwide dispersion and silky smoothness in frequency response. No other tweeter we know of moves so accurately and with so little distortion as our 1" soft-dome. This is accomplished by the strong magnetic field of 15,000 Gauss driving a dome that weighs a mere 0,2 grams, which is a great deal lighter than the usual tracking force required for a good turntable cartridge.
The distorting break-up so common with paper cone and dome tweeters is entirely prevented by suspending our tissue dome by its own sealed acoustic chamber, and by damping out resonances with a unique (sticky) damping fluid.
This design gives our tweeter the ability to handle transient and musical details so faithfully that it can be called ear opening. In spite of its lightweight the Braun dome can tolerate substantial amounts of power. The tiny voice coil stays cool by radiating all the heat through the very narrow coil gap of one one-thousandth of an inch right into the heavy one pound magnet.
The Crossover
No matter how good the drivers may be, only with a crossover of equal performance will a speaker perform at its best. Braun is so convinced of this that we use heavy eighteen ounce copper coils for perfect linearity and for minimum losses, as well as expensive metal film capacitors for long-term stability, low losses and for never changing frequency response of the speaker system.
Specifications
Driver Complement:
One 1" diameter soft dome tweeter
Two 7" diameter high compliance woofer
Speaker System
Frequency Response: 25 - 25,000 Hz (DIN)
Power Handling: 35 Watts (RMS) (DIN)
Efficiency: 88 dB for 2 Watt input at 10 feet
Crossover Frequency: 1,500 Hz ±2 dB/octave
Impedance: 4 Ω
Cabinet Finish: White acrylic lacquer on wood or Walnut veneer
Grille: Removable black double knit or beige Cloth Grille
Dimensions (H x W x D): 21-6/8" x 12-1/4" x 10-1/2"
Weight: 32,5 lbs (net)
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