SPL

SOUND PERFORMANCE – MADE IN GERMANY

https://spl.audio/en/professional-fidelity-en/

From the manufacturer:

SPL has been developing professional audio technology for over 35 years.
Sound studios all over the world rely on the outstanding sound quality.
Mastering studios demand the highest standards in terms of audio performance, because they put the finishing touches to music productions – with the proprietary SPL 120V technology.

In our Professional Fidelity series, we refer to this unsurpassed technology as VOLTAiR technology.

Experience music on the same level as the mastering sound engineer.
Infinite dynamic range.
Sense for spatiality.
Detail-rich, vivid, honest and plain simply beautiful.

This is SPL VOLTAiR technology.