With its geometric shapes, the concert hall resem­bles a space ship. (Photo: Adam Mørk)

The building looks like a space­ship that has just landed, in a green oasis near the Baltic Sea shore. An imposing plaza extends in front of the nearly 7000-square-meter struc­ture composed of oblique angles and expanses of glass. The “Latvia” concert hall, which opened in July 2019 along with a music school and music library in Ventspils, Latvia, is a visual treat – and not just from the outside.

Anyone who crosses the threshold of this concert hall, which cost approx­i­mately EUR 31 million, and makes their way into the larger of the two halls – the larger one holds about 600, the smaller about 150 people – will be amazed. Lamps remi­nis­cent of manta rays float high above people’s heads, elegant wooden ribs surround the view of the stage. The concert hall houses Latvia’s only public music library, a unique acoustic organ built by the German Johannes Klais, and what is prob­ably the world’s largest piano. The piano, which weighs 800 kg and is four and a half meters tall, is suspended on the wall three meters above the ground and is only acces­sible via a wooden stairway.

Library, school, and music studio

If after an event in the concert hall you have become curious about new music, you should take a look at the music library next door. With an area of more than 150 square meters, it offers edifi­ca­tion to students of the music school and it is also open to the public. Among other things, it houses an acousti­cally dense room including screen for very special music expe­ri­ences, as well as a sound studio for recording.

“Latvija’s” large audi­to­rium seats 600 people. (Photo: Lauris Aizupi­etis)

The building cost 31 million euros and is sure to impress. (Photo: Adam Mørk)

Its look was created by Stuttgart-based archi­tects haas­cook-zemm­rich. (Photo: Lauris Aizupi­etis)

“No day is like another”

This musical wonder­land is the work­place of Edgars Šifers. He started his job as tech­nical director there in August, after the concert hall was completed. Previ­ously, he worked as an IT system admin­is­trator for twelve years. He likes his new job and goes on to explain “No day is like another. Because the building is new, we are still learning to under­stand it.” As an IT specialist, he works with the building manage­ment system and he is respon­sible for elec­tricity, moni­toring tech­nology, fire protec­tion, and venti­la­tion. It’s the latter that occu­pies the bulk of his atten­tion in this start-up phase. “I learn some­thing new about the config­u­ra­tion of the venti­la­tion nearly every day,” he says.

Facility manager Šifers config­ures the air condi­tioning. (Photo: Lauris Aizupi­etis)

Several systems provide venti­la­tion and air condi­tioning for the concert hall. In total, there are nine central venti­la­tion systems and a decen­tral­ized system that works with indi­vidual units. While both concert halls are supplied centrally, decen­tral­ized facade venti­la­tion puts fresh air into play in the smaller rehearsal rooms and the music library, and this in an inno­v­a­tive manner.

Decen­tral­ized venti­la­tion “breathes”

A total of 74 FVPpulse units made by LTG AG of Stuttgart are installed in the rooms on the ground along the facade and these “breathe.” One fan apiece is installed in these units and a motor controls a flap which changes posi­tion every 20 seconds and thus regu­lates inflow and outflow — the breathing in and out, so to speak. Fresh air and exhaust air are taken in and blown out through the same opening in the wall. No venti­la­tion ducts are required, which makes instal­la­tion much simpler. The units work auto­mat­i­cally and also regu­late the CO2 level of the air in the rehearsal rooms.

When the “Inhala­tion” cycle starts, the outside air is drawn in through the facade opening and supply air filter.

The air flows through the heat recovery unit still warm from “Exha­la­tion” and is heated.

After­wards, the air passes through the fan’s inlet chamber (lower level).

The EC centrifugal fan trans­ports the air from the inlet chamber (lower level) into the pres­sure chamber (upper level).

In the upper level, the supplied air passes the silencer and the damper and flows into the supply air duct.

After leaving the supply air duct, the air is cooled or heated by the heat exchanger and is discharged through a supply air grille.

Further­more, they also contribute to the building’s basic concept to be energy-effi­cient. “In a room with three people, power consump­tion is less than 10 watts. That’s a great success,” says LTG exec­u­tive Ralf Wagner. The LTG engi­neers have also done great work with the heat recovery; a heat accu­mu­lator warms the air in the unit that is drawn in from the outside. “This way, we can achieve effi­ciency levels of up to 90 percent.” Addi­tional energy effi­ciency measures are a heat pump with approx­i­mately 400 geot­hermal probes and five venti­la­tion ducts under the concert hall that are each approx­i­mately 100 meters long.

For visi­tors to the music library and students of the music school, an optimal indoor climate and quiet venti­la­tion are essen­tial. This is ensured by decen­tral­ized venti­la­tion devices installed in the floor. (Photo: Lauris Aizupi­etis)

Venti­la­tion has to be quiet

With regard to venti­la­tion, in addi­tion to ques­tions of effi­ciency, acoustic values are espe­cially impor­tant. In the rooms of the music school where private lessons are given, a loud venti­la­tion unit would be extremely disrup­tive. “With the FVP pulse, there were strict noise spec­i­fi­ca­tions. We had to think about that together,” says Rudi Wein­mann, a regional sales director at ebm-papst, who has assisted LTG as a customer for more than 20 years. In each FVPpulse unit, there is an ebm-papst RadiCal, which is very quiet. However, the asym­met­rical intake situ­a­tion and the flap design of the units caused turbu­lence in the inflow to the fan, which gener­ated noise emis­sions that were too high. “Vortex plaits were created which directly hit the rotating impeller blades and thus produced a disturbing rotary sound,” explains Wein­mann. Together, the engi­neers at LTG and ebm-papst came up with the solu­tion to the problem: ebm-papst’s Flow­Grid. Mounted on the intake side, it splits up the vortex plaits and signif­i­cantly weakens them as they flow through. This reduced the sound pres­sure level and, finally, the noise emis­sion by 6 dB(A).

Edgars Šifers likes his job: “No day is like the other,” he says. (Photo: Lauris Aizupi­etis)

There is still poten­tial for improve­ment

The venti­la­tion works quietly and effi­ciently, but it can still be improved. At least this is what Edgars Šifers thinks. He is currently exper­i­menting with the control of the FVPpulse units based on the music school’s working hours. It is open from 8:00 AM to 9:00 PM. To save energy, the venti­la­tion units are switched off outside of these times. “However, when the units are only switched on at 8:00 AM, that’s not optimal for the indoor climate,” he says. “For now, we will switch them on at 6:00 AM and see how that goes. Perhaps in the future, it will be suffi­cient if we switch them on at 7:00 AM.” Just as in the small class­rooms where people prac­tice scales and rhythms, the adjust­ment of the venti­la­tion also requires some patience.