Напольная акустика — Joseph Audio PEARL Graphene

The Pearl Graphene is a floorstanding loudspeaker from Joseph Audio, the American company led by Jeff Joseph, and it is the model the brand also calls the Pearl3. US pricing has been reported at USD 44,999 per pair. It sits in a current catalogue that also lists the Perspective2 Graphene, Pulsar2 Graphene, Profile, Prism and Insider2.

Key specs that matter

Joseph Audio specifies a three-way layout with its Series/Parallel Asymmetrical Infinite Slope crossover, dividing the signal at 130 Hz and 2 kHz. Response in the listening window is held within 2 dB from 25 Hz to 20 kHz. Sensitivity is 86 dB SPL at 2.83 V RMS and 1 metre, measured anechoically in 4 pi space. Impedance is 8 ohm nominal with a minimum of 6 ohm. Each speaker is 1092 mm high, 279 mm wide and 457 mm deep. The pair ships in four cartons with a total shipping weight of about 145 kg.

Engineering and use context

The driver complement is a 1 inch tweeter, a 7 inch midrange and two 8 inch woofers. The woofers use aluminium cones and were created with additional magnet mass and a copper pole piece, mounted in a cast zinc alloy frame whose narrow fingers are meant to reduce internal reflections. Around the edge of the tweeter voice coil sits a field array of magnets, and the area behind the dome is kept free of reflective materials. The woofer, midrange and tweeter crossover circuits are physically independent, and each network is individually calibrated. Joseph Audio places the midrange and tweeter in their own enclosure rather than sharing a box with the bass drivers. The two enclosures are linked by solid brass points, which isolate the tweeter and midrange from the woofers. Signal enters through Cardas vise-type input terminals, a patented design that carries CE approval. The asymmetrical crossover uses different slopes for the high-pass and low-pass sections of each driver, an approach Joseph Audio applies across its current Graphene range.

Pairing

The impedance never falls far below its nominal rating, and Joseph Audio notes that a true 8 ohm load partners with a broad range of amplifiers, including valve designs. When comparing its sensitivity with 4 ohm speakers, the maker advises adding 3 dB to the Pearl's figure, since a 4 ohm load draws twice the current. At Axpona 2023 it was demonstrated with Doshi Audio electronics, Cardas Audio cabling, a J.Sikora turntable and Berkeley Audio Design digital components.

Alternatives

The Joseph Audio Perspective2 Graphene is a compact floorstander in the same range, also built with graphene coated magnesium woofers, Sonatex Hexadyn tweeters and an Asymmetrical Infinite Slope crossover.