RapcoHorizon STBLOX Speak-On Cable Tester for NL4 Cables

The RapcoHorizon STBLOX is built for live sound engineers and production technicians who need fast, accurate Speak-On cable verification before and during shows. Housed in RapcoHorizon's standard BLOX chassis, it delivers a compact, rugged form factor that holds up to the demands of touring and installed audio environments where unreliable speaker cable connections cost time and performance.

With two NL4MP Speak-On panel-mount connectors and four independent push-button switches — one per pole — technicians can isolate and test each conductor path individually, making it straightforward to identify intermittent faults, wiring errors, or damaged poles in multi-conductor Speak-On assemblies. Four red LED indicators give instant visual confirmation of continuity for each pole without requiring a separate meter or adapter.

The STBLOX is part of the broader Tester BLOX family, which also covers XLR, 1/4-inch, and continuity testing scenarios using the same chassis and build standard. For production teams that need a consistent, no-frills cable testing toolkit across connector types, the BLOX series provides purpose-built tools that travel easily and perform reliably in rack rooms, stage setups, and permanent installs alike.