The best part about the Isarphilharmonie at Gasteig HP8 could have been the foyer, until Utopia Orchestra owned it.

This foyer is exciting, industrial, and perfectly sized. Built as a temporary 2,000-seat concert hall while the original hall is being reinvented, the venue makes use of an old factory building for the front-of-house: ticketing, café, cloakrooms, toilets, circulation, and probably a few spaces I never found.
Once the bell rings, it is time to percolate through the narrower entry towards the new-build concert hall and its tighter circulation spaces. Locals may know the routes to avoid bottlenecking, but there are enough newcomers (me) to jam the main access.
The concert hall itself is black, continuing the industrial-chic language, with steel wire mesh as balcony fronts. Suitable choices for a temporary hall. The seats and aisles are comfortable, but one cannot quite shake the feeling of being in an ad-hoc space.
The bare walls above the stage may contribute to that impression, but the main giveaway is the sawtooth-shaped ceiling. This curious design decision seems to reduce overhead reflections noticeably, from my row 18 seat. The sound envelopment lacked one dimension: clear sound coming from the sides, some from the rear, but not much from above. A clear contrast with KKL Luzern.
I also found that the hall did not favour blend in the string sections. Perhaps a result of the sawtooth ceiling and a largely horizontal diffusion pattern covering the entire room, including the side walls of the stage. The effect was a very analytical image of the orchestra, with individual instruments presented individually, too much to my taste.
Thankfully, Maestro Teodor Currentzis and his extraordinary Utopia Orchestra brought a programme with real punch, and an energy that made us forget the black walls, the two-dimensional sound, and the wire mesh.
Vilde Frang was stunning in Berg’s Violin Concerto, Dem Andenken eines Engels. Even more impressive, she returned as first violinist for Mahler’s First Symphony, Titan.
This time, almost all musicians, except the cellists, were standing, moving with the music, and physically magnifying each phrase. It was contagious and exhilarating, but it also seemed to improve the blend of the orchestral sound. Perhaps the movement of the instruments introduced just enough “fuzz” into the otherwise analytical reflection patterns. The orchestra sounded phenomenal, intimate, celebratory, inviting, passionate.
We were all carried away to a standing finale, the audience charged with as much adrenaline as the musicians. Maestro Currentzis and the Utopia Orchestra blew the sawtooth roof off the hall. I absolutely loved it.
With that Orchestra, the hall becomes great value for a temporary venue.
Luckily, there was still enough left in the tank for a backstage chat and a drink with musicians, back in that great foyer, where the bar closed far too soon.
