A toJazZ in Sofia, Bulgaria. Pure Jazz & Clarity with Vera20!

The 15th anniversary of the A to JazZ Festival, held from July 2–5, 2026 at South Park 2 in Sofia, gathered a total audience of 60,000 music enthusiasts over four days, reaching up to 20,000 attendees per day. As one of the continent's most significant outdoor jazz events, A to JazZ presents a rich blend of traditional acoustic jazz, modern improvised sounds, and international world music – on a single open-air setting that required "a powerful, extremely precise sound reinforcement system capable of serving a massive footprint while maintaining pristine sonic clarity across diverse musical styles."

From delicate acoustic jazz to powerful fusion and international world music, the diverse line-up put the system through its paces — with every act relying on the same rig in front of up to 20,000 listeners a day.

A Milestone Anniversary, Four Days Running.

For its 15th anniversary, A to JazZ once again transformed South Park II into a large-scale open-air concert venue. The 120 × 80-metre site placed significant demands on the sound system: one main PA had to maintain consistent tonal balance and intelligibility across the entire audience area, from the front rows to the very back.

The Challenge

The primary acoustic challenge was covering the expansive 120 × 80-metre outdoor area while maintaining a perfectly linear frequency response and consistent tonal balance throughout the entire audience area.

The musical program raised the stakes further. Delicate, dynamic acoustic jazz instruments and sensitive open microphones demanded an exceptionally quiet stage, while powerful modern jazz fusion called for uncompromised low-end performance. The system therefore needed to deliver powerful low frequencies into the audience area while keeping low-frequency spill off the stage to preserve clarity for the performers.

The Solution

Despite its remarkably compact footprint and light weight, the TW AUDiO VERA20 system delivered exceptional SPL output with ultra-precise directional control and exceptionally linear dispersion across the entire 120 × 80-metre field.

To tackle the low-end requirements and stage clean-up, 16 x S32 subwoofers were deployed in a cardioid sub array. This configuration provided maximum rejection behind the sub array, creating an exceptionally quiet stage environment.

This allowed sensitive acoustic jazz instruments and vocals to be amplified without low-frequency bleed, phase issues or feedback. Coupled with VERA20’s natural, crystal-clear sound character, the setup preserved every acoustic nuance while providing an immersive, high-fidelity experience for up to 20,000 jazz enthusiasts.

Main PA	32× VERA20
Subs	16× S32 (cardioid configuration)
Sub/Infrasub	4× B21
Amplification	8× Powersoft X4

Despite its remarkably compact footprint and light weight, the TW AUDiO VERA20 system delivered an exceptional SPL output with ultra-precise directional control and exceptionally linear dispersion across the 120m x 80m field. Nikolay Penkov - Audio Consultant, NAT Ltd