Because Roland has officially abandoned the Edirol brand, you cannot buy the Super Quartet from a legitimate store. You cannot download it from Roland Cloud. It has become (software no longer sold or supported by its copyright owner).
If you're interested in downloading the Edirol Super Quartet VST, here are some steps to follow: Edirol Super Quartet Vst Free Download
Official sales and support from Roland/Edirol have ended. This means "free" downloads found on third-party sites are often unauthorized and may contain malware or be unstable on modern OS versions. Because Roland has officially abandoned the Edirol brand,
The (HQ-QT) is a vintage software synthesizer from the early 2000s that remains a "cult classic" among music producers, particularly those who appreciate early Touhou Project soundtracks or retro "Y2K-era" game music. If you're interested in downloading the Edirol Super
Noise Gate: Helps reduce background noise and hum, ensuring a clean and polished sound.
It is most famous for the "St. Concert" piano preset , which became iconic through its use by the developer ZUN in the Touhou series.