Siltech Debuts the Pantheon Loudspeaker By John Atkinson October 28, 2007 — The invitation looked intriguing: "We are happy to welcome you to The Netherlands in September for the offical introduction of the Siltech Pantheon Loudspeaker." Siltech introducing a loudspeaker? I was well familiar with the Dutch company, celebrating its 25^th anniversary next year, as a cable manufacturer. Indeed, some of the first high-end cables I had found to sound better than what I had been used to were Siltechs, back in the mid-1980s. Paul Bolin had been impressed by his auditioning of more recent G5 models in 2004. And Siltech's founder, Edwin van der Kley, is married to the irrepressible Gabi van der Kley, principal of Crystal Cable with whom I had had a rather intense breakfast meeting with during last May's Home Entertainment 2007. (All conversations with Gabi are intense.) But loudspeakers?

I was planning on visiting the UK in late September to attend to some family matters, so it was hardly "a bridge too far" to tack a day on to that trip to visit Siltech in Arnhem, Holland.

There, in the restaurant associated with Arnhem's historic Roosendael Castle, Edwin unveiled the Pantheon to an assembly of journalists, dealers, and distributors. The Pantheon is intended to be the flagship of a range of speakers, and will cost upward of $120,000/pair in the US. Weighing 310 lbs and standing 63" tall, the speaker combines a pair of isobarik-arranged 16" Audio Technology woofers in a large, reflex-loaded bass bin with a 7" AT midrange unit in a separate enclosure, and a curved, 19" x 5" electrostatic tweeter. Internal wiring is, of course, all Siltech G7 silver-gold alloy, and the fourth-order crossover features 5.5 lb air-core inductors and high-quality capacitors.

The woofer tuning is unusual, in that the design goal for the system Q was very low, 0.5 with the port open, 0.38 with it closed. This overdamped alignment, optimized with extensive computer modeling of the speaker's interaction with the room acoustics, is essential, Edwin van der Kley feels, due it its tuning not being adversely affected by room resonant modes. Even with this low Q, the Pantheon's bass extension is said to be a low 18Hz, –3dB. The speaker's overall directivity is said to be carefully controlled. All the design work was perfomred using a set of analytic programs from Comsol in Sweden.

The very low-mass, high-sensitivity tweeter has a diaphragm just 0.03mm in thickness and is specified as having useful HF extension to 39kHz. It is sourced from Cadence in Pune, India, the high-end division of one of the sub-continent's largest speaker manufacturers, and it emerged in conversation with the van der Kleys and Cadence's managing director, Ajay Shirke, that the Indian company has taken a partnership interest in Siltech. Certainly, Edwin (right in my photo) looks pleased with the turn of events, while Stereophile contributor and erstwhile Hi-Fi News editor Steve Harris (center) and current Hi Fi News editor Paul Miller (left) examine the Pantheon close-up.

Considering its bulk, the Pantheon looks extremely elegant, thanks to the styling, the result of the work of Traditional Arts Ltd, a London-based associate of the Prince of Wales Charity Foundation. The lustrous, hand-finished piano-black lacquer is complemented with either aluminum or gold-plated metal parts, and is finished off with a trim of bull-hide leather from Hulshof Royal Dutch Tanneries.

But what of the sound? Siltech had set up the speakers in the very large room at the Roosendael restaurant with a full dCS Scarlatti digital front-end and Pass Labs X-1 preamp and X-250.5 power amplifiers. The room was hardly suitable for critical listening, but the Pantheons played loudly without strain. While lateral dispersion seemed excellent for a design with an electrostatic tweeter, it became apparent that there was a sweet spot in the vertical listening window. On that axis the integration between the midrange unit and the electrostatic tweeter was seamless. Acoustic objects hung in the air between and behind the speakers and there was no sense of anything within the soundstage being associated with the physical loudspeakers. And the bass was to die for, with a superb combination of the extension and definition.

I understand that Siltech's Pantheon will be making its US debut at January's Consumer Electronics Show in a room at the Venetian, driven by Krell amplification. That's a room I will be sure to visit on the first day of the Show!