Silja Serenade – full retrofit of the onboard communication system
For one of the Baltic’s busiest passenger ferries, a retrofit onboard communication system was essential. Silja Serenade carries thousands of passengers and crew every week. When it came time to replace an aging intercom, the challenge was clear: modernize without tearing out miles of cabling or disrupting operations.
Zenitel’s retrofit team took on the task, building on earlier work to upgrade the vessel’s PAGA system. The goal was not only to replace old hardware, but to deliver a communication platform flexible enough to adapt to crew needs and operational demands for years to come.
A Flagship on the Baltic Sea
Built in Finland in 1990, Silja Serenade is a cruise ferry operated by Tallink Silja Line on the Helsinki–Stockholm route via Mariehamn. The ship is famous for its 143-meter promenade, lined with shops, restaurants, and cabins — a design that made headlines when she entered service. With capacity for 2,800 passengers and 450 crew, she remains a flagship on the Baltic Sea, where reliability and efficiency are vital.
Retrofit Onboard Communication System – From ASA to ICX AlphaCom
The retrofit replaced an aging ASA 101 two-wire digital intercom system with the modern ICX AlphaCom platform, building on the Exigo PAGA system installed three years earlier.
The scope was extensive: 16 NVT 48-port switches to migrate hundreds of endpoints onto IP, around 550 IP Deskmaster phones in crew cabins, offices, shops, and restaurants, and about 70 TFIE stations across outdoor areas, machinery rooms, and mooring decks. In passenger cabins, old ASA telephones were removed and replaced with loudspeakers using the old telephone wires, enabling clear PA broadcasts through ICX AlphaCom integrated with Exigo.
From the start, Zenitel worked closely with the vessel owner and onboard crew to ensure the setup reflected real operational needs.
“In the end it looked very nice and clean, but it took precision to get there. The installation was completed in drydock, with adjustments and training continuing after departure,” explains Thomas Aas, Marketing & Communication Lead at Zenitel Maritime & Energy.
Elevators, Flowire, and Smart Engineering
One of the more complex tasks was upgrading the elevators. Existing panels were kept but connected through TKIS-2 kits and FCDC3 Flowire technology, reusing old two-wire cabling to deliver full IP functionality.
This required detailed engineering and a steady hand to make the system both neat and reliable.
“With so many lines coming in, precision is everything,” Thomas notes. “If the system doesn’t start correctly, calls won’t reach the right endpoints — and you can imagine the chaos if it doesn’t work, in such critical spaces.”
Keeping Pace During a Major Refit
The retrofit took place during a major four-week docking period. Two extra weeks were added for unrelated upgrades to navigation, fire alarm, and engine monitoring systems, but Zenitel’s installation was completed on time. After the drydock, the team returned for a few days of fine-tuning and crew training.
This highlighted how communication systems are deeply connected to the vessel’s wider safety backbone. The new fire alarm, for example, was integrated directly with the Exigo PAGA, ensuring safety alerts could be broadcast instantly throughout the ship.
Collaboration as the Key Enabler
Retrofit projects rarely follow a straight line, but collaboration was key to making the project a success. Zenitel worked closely with the vessel owner, the onboard technical crew, and its own engineers to solve challenges as they arose.
“One of Zenitel’s strengths is closing loopholes early and streamlining the process,” Thomas says. “Challenges will always come up, but with skilled engineers and close teamwork, issues are solved onsite. In the end, everything was running smoothly — and I even tested the sound quality in the engine room and over the PA. To hear, be heard, and understood: that’s what it’s all about.”
Smarter Retrofits for the Future
The Silja Serenade retrofit reflects a wider movement in the Baltic ferry market. While most vessels in the region have already upgraded their PAGA systems to Exigo, many still rely on outdated intercom and telephone systems. Feedback from shipowners highlights the flexibility of ICX AlphaCom, which provides:
- A modern intercom system for daily use and safety-critical priority calls.
- A fully integrated talkback system for operational communication and conferencing.
This dual capability, combined with the ability to reuse existing cabling, makes retrofit onboard communication systems a cost-effective and sustainable choice. For ferry operators, it means reducing material waste, minimizing downtime, and future-proofing communication systems without compromising on quality.