Klipsch PRO-650T-RK sandstone

The PRO-650T-RK takes the shape of a realistic rock to blend into a flower bed, along a pathway, or near a pool, while delivering hi-fi quality sound. Klipsch incorporates the same acoustic principles used in its indoor speakers, with a dedicated Tractrix horn and a 16.5 cm IMG woofer. The speaker is sold individually.

A Tractrix horn designed for outdoor use

Klipsch has used Tractrix-profile horns since 1989 on its indoor speakers. The principle is simple: the horn’s shape controls how sound propagates from the tweeter, which improves efficiency and reduces distortion. On the PRO-650T-RK, Klipsch designed a specific Tractrix horn adapted to the constraints of outdoor listening. Horizontal dispersion reaches 105°, a wide angle that makes it possible to cover a broad listening area without creating too pronounced a dead spot between two speakers.

The tweeter is a 2.54 cm aluminum dome coupled to this horn. The system sensitivity reaches 90 dB, a high value that means in practical terms that the speaker makes the most of every watt supplied by the amplifier: it plays loud with little power, and the dynamic headroom remains comfortable even at moderate volume.

An IMG woofer built for the outdoors

The 16.5 cm woofer uses an injection-molded graphite (IMG) cone. This material, which Klipsch uses across its entire Reference range, is both light and rigid. The light weight allows the cone to react quickly to transients; the rigidity limits unwanted deformation that colors the sound, especially in the lower part of the spectrum. Frequency response extends down to 100 Hz (± 3 dB), which is respectable for a satellite speaker of this size, without claiming to replace a subwoofer. Outdoors, where there are no walls or ceiling to reinforce bass through reflection, a dedicated subwoofer (such as the PRO-10SW-RK from the same range) is still recommended if solid low-end foundation is desired.

Compatible with 8 ohms, 70 V, and 100 V

This is one of the understated but important strengths of this speaker: it includes a multi-tap transformer that makes it compatible with three types of systems. In 8-ohm mode (bypass), it connects directly to a conventional hi-fi amplifier. In 70 V or 100 V mode, it integrates into a distributed audio system, the type of wiring used in commercial installations and large gardens where many speakers are distributed over long cable runs.

The transformer offers several power settings: 6.25 W, 12.5 W, 25 W, and 50 W in 70 V; 12.5 W, 25 W, and 50 W in 100 V. Selection is made via a rotary switch located underneath the speaker, accessible without tools. This adjustment makes it possible to balance the volume among the different speakers in an installation, taking into account their distance from the listening areas.

Fiberglass, stainless steel, and IP45 certification

The enclosure is made of reinforced fiberglass, UV-treated to resist aging in the sun. The hardware is stainless steel. The internal acoustic materials are waterproof. The whole unit is IP45 certified, which corresponds to protection against solid objects larger than 1 mm (fine dust, insects) and against low-pressure water jets from all directions. In practical terms, the speaker can withstand rain, automatic sprinklers, and seasonal bad weather. It is not, however, intended for immersion, even partial.

The speaker weighs just under 5 kg and measures 277 × 245 × 341 mm. It sits on the ground without mounting, held in place by its own weight and flat base. Two finishes are available, granite and sandstone, to match different types of rock gardens and outdoor spaces.

Technical Specifications

Design and use

• Type: outdoor satellite speaker (rock effect)
• Acoustic design: Tractrix horn-loading for high efficiency and low distortion
• Dispersion: wide horizontal coverage for even sound distribution
• Applications: residential, commercial installations, gardens, terraces, parks

Drivers

• 2.54 cm aluminum dome tweeter
  • Coupled to a new-generation Tractrix horn
  • 105° dispersion
• 16.51 cm IMG (Injection Molded Graphite) woofer

Audio performance

• Frequency response
  • 100 Hz – 24 kHz (± 3 dB)
  • 92 Hz – 30 kHz (± 6 dB)
  • 77 Hz – 35 kHz (± 10 dB)
• Sensitivity: 90 dB
• Coverage angle: 105°
• Power handling: 100 W (peak)

Connectivity and installation

• Compatibility: 8 ohms (bypass), 70 V / 100 V lines
• Integrated multi-tap transformer
  • 70 V: 6.25 W, 12.5 W, 25 W, 50 W
  • 100 V: 12.5 W, 25 W, 50 W
• Power selector: tool-free rotary switch (easy access under the speaker)
• Installation suitable for small- to large-scale distributed systems

Construction and durability

• UV-treated reinforced fiberglass enclosure
• IP45 certification
• Waterproof acoustic materials
• Stainless steel hardware
• Designed for long-term outdoor use in demanding weather conditions

Dimensions and weight

• Dimensions (W x H x D): 277 x 245 x 341 mm
• Weight: 4.98 kg