OPERA GRAND CALLAS SPECIAL EDITION PADOUK

Three-way floor-standing speaker system representing the reference model in the Opera Loudspeakers range. Its design combines a sophisticated acoustic architecture, a selection of drivers developed specifically for the brand and handcrafted construction, with particular attention to resonance control and the proper integration of the different frequency sections.

The cabinet is constructed from MDF and multiple layers of wood, with wall thicknesses ranging from 25 to 50 mm, the latter being used for the front panel. The total internal volume is 92 litres, divided into an 80-litre chamber dedicated to the woofers and a separate sealed enclosure for the midrange driver. The structure incorporates internal bracing and features a front panel that is internally machined around the drivers, a solution designed to reduce turbulence and unwanted reflections. The midrange chamber is also lined with highly absorbent expanded polyurethane foam sheets, which minimise internal reflections and help preserve midrange transparency.

The low-frequency section employs two 8-inch Scanspeak woofers, developed to Opera's specifications, featuring aluminium cones, rubber surrounds, symmetrical magnetic circuits and stabilisation rings. These drivers are designed to provide controlled output and operate linearly up to 1,500 Hz, despite being crossed over at 200 Hz. The midrange is handled by a driver featuring an annealed polypropylene cone, a symmetrical magnetic circuit and a black ABS phase plug. The latter helps eliminate resonances that can develop between the dust cap and the pole piece, contributing to natural reproduction of voices and instruments. High frequencies are reproduced by a ScanSpeak 9700 tweeter, while the reflected sound field is handled by two additional rear-mounted tweeters arranged in a natural dipole configuration. This auxiliary section contributes to a wider and deeper soundstage without directly interfering with the front-facing output.

The crossover features a configuration developed to manage the different acoustic sections independently, with the woofers and midrange crossed over at 200 Hz and subsequently treated as a single system through a low-pass filter. This solution allows the transition between the mid-bass section and the tweeter to be managed while maintaining control over the phase relationships between the drivers. The circuit employs Mundorf capacitors, MOX resistors and OFC copper inductors, while the sections dedicated to the tweeters and mid-bass drivers are mounted on separate PCBs to minimise self-induction effects and interference. The two rear tweeters also feature an independent crossover, allowing both the crossover frequency and attenuation level to be adjusted according to the characteristics of the listening room. The system also supports bi-amplification.

The Special Edition is distinguished by its Padouk finish, a wood species with a coral-red colour that gradually develops towards greyish-brown shades over time. In addition to its aesthetic qualities, this wood is valued for its hardness, stability and durability. The construction also features a 5 mm aluminium top plate engraved with the model name, replacing the previous glass element, together with a redesigned rear connection plate made from the same material. Internal wiring uses AudioQuest LGC (Long-Grain Copper) conductors, featuring a semi-solid concentric construction and a 16 AWG gauge. This geometry keeps the individual strands more stable within the cable and helps minimise electrical and magnetic interactions between conductors, preserving signal integrity along the path between the crossover and the drivers.

To facilitate integration into different listening environments, Grand Callas incorporates dedicated adjustments for low-frequency response and bass-reflex output. A switch located near the input terminals allows the woofer response to be modified: in the upper position, bass frequencies become more prominent, a setting suited to low-volume listening or larger rooms, while the lower position provides a more linear and extended response. The bass-reflex ports can also be blocked, converting the enclosure into a sealed configuration characterised by greater damping and tighter bass reproduction. These adjustments can be made independently on each speaker, allowing the two systems to be adapted to their respective installation conditions.

The shaped front baffle helps maintain accurate soundstage focus even at relatively short listening distances, starting from approximately 1.5 metres. The recommended distance from the rear wall is at least 20 cm, although the available response adjustments make it possible to manage room interaction and achieve a suitable balance in different listening configurations.

The nominal impedance is 4 Ohms, and maximum power handling reaches 500 W without clipping. The speakers are designed to work with amplifiers rated from 10 W upwards, while the specific crossover architecture supports bi-amplification but not tri-amplification.

Technical Specifications

• Type: Three-way floor-standing speaker; rear bass reflex; rear-firing dipole radiation system
• Finish: Padouk
• Tweeter: 1 x 25 mm Scan-Speak 9700, without ferrofluid, with double decompression chamber
• Midrange: 1 x 178 mm, annealed polypropylene cone, phase plug
• Woofer: 2 x 203 mm long-throw drivers, aluminium cones, rubber surrounds, symmetrical magnetic circuits with stabilisation rings
• Rear Radiation System: 2 tweeters in a natural dipole configuration
• Crossover Frequencies: 200 Hz / approx. 2,000 Hz
• Frequency Response: 32–25,000 Hz (-3 dB)
• Sensitivity: 89 dB (2.83 V / 1 m)
• Nominal Impedance: 4 Ohms
• Minimum Impedance: 3.2 Ohms
• Maximum Power Handling: 500 W (without clipping)
• Recommended Amplifier Power: From 10 W
• Crossover: Separate tweeter and mid-bass filter sections on independent PCBs; Mundorf capacitors, MOX resistors and OFC copper inductors; bi-amplification capability
• Adjustments: Low-frequency response adjustment switch; independent crossover for rear tweeters with adjustable crossover frequency and attenuation
• Enclosure Loading: Rear bass reflex; ports can be blocked for sealed-enclosure operation
• Internal Wiring: AudioQuest LGC long-grain copper, semi-solid concentric construction, 16 AWG
• Positioning: Minimum distance from rear wall 20 cm; nearfield listening from approximately 1.5 m
• Dimensions (H x W x D): 1,300 x 310 x 550 mm
• Weight: 75 kg per speaker