Purifi built its name on Eigentakt amplifier modules and a near-obsessive approach to measurement. The Purifi SPK16 Kit is that same engineering culture applied to something DIY speaker builders can actually put their hands on: a stereo pair of driver-and-crossover kits, first shown at High End Munich back in 2023, now finally shipping now that its waveguide-loaded tweeter has reached full production.
What the Purifi SPK16 Kit Actually Includes
The kit itself is a 2-way, passive-radiator-loaded design: two PTT1.3T04 tweeters with a 147mm waveguide, two PTT6.5X04 extended-stroke woofers, and four matching PTT6.5PR passive radiators, all with black anodized aluminum cones. A mass-tuning kit is included to adjust the passive radiators’ bass alignment after assembly. What the Purifi SPK16 Kit deliberately leaves out is just as telling: no cabinet, no crossover components and no damping material are supplied. Purifi’s own build description is explicit that this is not a step-by-step manual but “a guide showing how a cabinet can be made,” aimed squarely at builders who already know their way around a table saw.
The Same Measurement Obsession, Applied to a Cabinet
Where the Purifi SPK16 Kit distinguishes itself from a typical driver bundle is in how it was engineered. Purifi used model-based design in Comsol and Matlab to shape the box before a single prototype existed, then verified everything with gated far-field measurements, near-field driver and passive-radiator scans, and a microphone-in-box technique to reconstruct accurate bass response below the limits of a normal anechoic gate. The passive radiators sit in a force-cancelling configuration – one on each side of the cabinet – specifically to cancel out unwanted enclosure vibration rather than fight it with brute-force bracing.
Full VituixCAD project files and CTA-2034-style spinorama measurements are published alongside the kit, so builders can inspect – or redesign – the crossover Purifi engineered rather than take it on faith. Complete documentation, including the build description and driver datasheets, is available on Purifi’s own SPK16 Kit product page.
Purifi is candid that this particular kit is not for everyone: its own FAQ points builders who aren’t confident building a cabinet toward a future, fully-inclusive kit that will ship complete with enclosure and crossover. Until then, the Purifi SPK16 Kit remains a drivers-and-know-how proposition, aimed at the DIY community Purifi says it wants to keep adapting the design.
Pricing and availability
The Purifi SPK16 Kit is listed at DKK 14,400 (tax excluded) for a stereo pair of driver and passive radiator sets plus the mass-tuning kit. Cabinet materials, crossover components, damping foam, screws and a Speakon connector must be sourced separately by the builder. At the time of writing the kit was shown with a 10-12 week shipping estimate once ordered.
Key specifications
- Design: passive, 2-way, passive-radiator loaded, force-cancelling passive radiator configuration
- Tweeter: 1x PTT1.3T04, 1.3-inch with 147mm waveguide
- Woofer: 1x PTT6.5X04, 6.5-inch extended-stroke, black anodized aluminum cone
- Passive radiators: 2x PTT6.5PR, black anodized aluminum cone, mass-tuning kit included
- Enclosure (as designed): 250 x 450 x 300mm, cabinet not included
- Bass extension: 32Hz at -3dB (as modeled by Purifi)
- Crossover point: approximately 1.8kHz
- Price: DKK 14,400 (tax excluded) per stereo pair kit, cabinet and crossover parts not included
