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.
Crossover
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.
Specifications
Drivers:
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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