What is stereo?

There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.

H.H. Scott '59

Dali DaCapo loudspeakers

The Dali DaCapo is a supremely neutral musical instrument over a broad frequency band, capable of reproducing an accurate illusion of the natural ambience of the recording venue and of the relative position of the musicians on a stage. The Dali DaCapo is not a high efficiency loudspeaker, nor is it a "loud and proud" party animal. What it can do with unparallelled grace and precision is disappear on those rare and precious occasions ehen the artist's performance and the labours of the studio engineers place you in the palpable presence of living music. If this is the experience you are interested in, then the Dali DaCapo will bring you years of listening pleasure.

Ribbon design
Theoretically, there are two approaches to the construction of a ribbon driver: 1) a single, pure aluminium ribbon, or 2) several aluminium ribbons electrically connected in series and laid out in parallel on a foil backing. The pure aluminium ribbon has the lowest mass, but also several disadvantages. For one thing, current only passes through the magnetic field once, which means low efficiency, and secondly, the impedance of such a ribbon would be very low, making the loudspeaker compatible with only the most esoteric (and expensive) amplifiers. Thhis would be in conflict with our express intention to make the Dali DaCapo compatible with economically amplifiers of good quality. To achieve reasonable efficiency and an acceptable impedance, we opted for 4 aluminium conductor tracks on a foil backing with a thickness of 12 micrometers. This yields an impedance of almost 4 ohms, with virtually no phase angles, making the Dali DaCapo child's play for any quality amplifier.
A magnetic gap in excess of 15 mm will not be uniform, with force decreasing towards the center of the field. Thus the magnetic force exerted on the ribbon closest, to the magnets will be greatest, since they are electronically in series. By employing aluminium conductor tracks of different width, wee vary the current density, thus compensating for variations in the strength of the magnetic field.

The crossover network is a linear phase 3rd order filter with large air core inductors and capacitors selected after extensive listening tests. The choice of internal cable was also the result of listening sessions: LC-OFC (Linear Crystal Oxygen-Free Copper) for the ribbon driver and 2,5 mm oxgen-free cable for the bass driver. The total system impedance is approx. 4 ohms, but because of the frequency indpendent nature of the load, the Dali DaCapo is a suitable partner for any quality amplifier. The crossover, which includes a fuse to protect the ribbon, is conveniently located at the bottom of the loudspeaker. The generous screw terminals accept banana plugs, spade lugs and cable diameters up to 10 mm.

Cabinet design
In the Dali DaCapo form reinforces function. The cabinet, a radical departure from the garden-variety loudspeaker enclosure, has side panels of MDF, a material with high density and excellent internal damping. The side panels of the bass section are 28 mm MDF. The same material is used in a 45 mm thickness for the ribbon section. The rear panel is assembled from three sections of the finest quality chipboard which join at odd angles and reinforce each other in an extremely rigid system. The front panel of the Dali DaCapo is also a special sandwich construction, with an outer section which is mechanically isolated from the rest of the cabinet using a visco-elastic damping board. The bass driver is mounted directly on this board for effective damping of cabinet resonances. Internal bracing has been carefully calculated through modal analysis and three adjustable spikes form a solid foundation for the Dali DaCapo, allowing the listener to tilt the speaker at just the right angle for a given listening position.

Woofer :  10 x 40" membrane driven with 8" woofer
Midrange/ Tweeter :  40" ribbon
Frequency Response:  45 - 20 ,000 Hz (±4 dB)
Impedance:  4 Ω
Sensitivity:  85 dB/1m (2,83 V)
Recommended Amplifier:  50 to 200 W/channel
Dimensions (W x H x D):  450 x 1180 x 310 mm (18" x 86-1/2" x 12")

Weight:  30 kg

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