Canto USA’s RETRO Series LED retrofit Teatro Regio project in Turin, Italy updated the theatre’s older halogen houselights to fully dimmable LED while meeting strict constraints: no access to the false ceiling, smooth low-end dimming on the venue’s existing dimmers, and minimal disruption to the theatre’s schedule.
The Teatro Regio has a long history dating back to 1740 and the current auditorium opened in 1973 after rebuilding. As part of a larger modernization to improve technology and energy efficiency, Teatro Regio replaced older halogen flood lamps with LED fixtures. Canto USA spoke with Enzo Trovato of Decima 1948 about the project and the decision to use the RETRO Series.
Project goals and partners
Decima 1948 won the tender to upgrade stage machinery and provide a lighting package for a smaller stage; the RETRO Series was selected for house and stage flood replacements. Canto USA International coordinated with project partners and recommended the RETRO Series because it could be customized to the existing openings and retained smooth phase-dimming behavior on the theatre’s conventional dimmers.
For the project Canto USA International connected Decima 1948 with Zalight to ensure component compatibility and on-site support during adjustments.
Constraints: keep the existing infrastructure
One of the primary requirements was to avoid opening the false ceiling to run new electrical or signal cabling. The theatre also required consistent output and stable dimming, including at very low brightness percentages.
“The main aim for installing the new LED light fixtures was not to touch the false ceiling for the passage of new electrical or signal cables,” Trovato said. “It also had to have excellent dimming and stability of the LED even at a low percentage of brightness.”
Customizing the RETRO installation
The ceiling openings at Teatro Regio were square and required adapter plates so the RETRO units could fit without cutting or reworking surrounding plasterwork. Canto USA fabricated adapter plates to match the openings and allow a direct mechanical and electrical fit. With those plates in place, all 37 RETRO units were installed to match the existing layout.
The resulting configuration was effectively plug-and-play—RETRO modules mated with the existing connectors and dimmer system, while final optical adjustments were left for on-site tuning.
Installation timeline and final adjustments
The on-site team completed the main installation in about one week. A further three days were used for lens swaps and fine-tuning light levels and beam shapes to the theatre’s needs. That tuning ensured smooth low-end dimming and consistent color rendering across all fixtures before handing the space back for performances.
The coordinated approach—custom adapter plates, RETRO’s compatibility with existing dimmers, and on-site optical adjustments—allowed the theatre to modernize lighting with minimal disruption and without invasive ceiling work.
Canto USA’s RETRO Series Fully Dimmable LED Retrofit Houselights
Canto USA’s RETRO product family (including RETRO-Fusion® 2.0 and RETRO-Passive® 2.0) is designed to be 0–100% phase dimmable on legacy SCR, TRIAC, and IGBT dimmers while remaining compatible with modern dimmer systems. The RETRO units are offered in a range of color temperatures and CRI options and can be adapted to older houselight openings with custom mounting plates. For details on recent product updates to the RETRO line, see the Canto USA update post: Canto USA Upgrades the RETRO Series with Fusion 2.0 and Passive 2.0.
If you are evaluating a houselight LED retrofit for a historic theatre or venue and need a solution that preserves existing dimming and minimizes ceiling work, contact Canto USA to discuss retrofit options and mounting customizations.
