There are several artists with this name:

1) Experimental/noise outfit creating collages of sound and voice active between 1986 - 2004. They've created deeply anxious collages of sound and voice in a mixture of fear and beauty. There are some places where they scream their faces off, but mostly it is the nature of the sounds themselves: hordes of insects, demonic sighs, electric buzzes, rumbles, creaking that gets under your skin and into your head, whether you want it to or not.
First incarnation (1986 - 1997): Jon Carlson (a/k/a St. Degeneratus), Christoph Heemann (a/k/a Herr Mücke), and Achim Flaam (a/k/a Dr. Tengelmann)
Second incarnation (1999 - 2004): Jon Carlson, R. Stanford King, and Wes Weresch (a/k/a Wesley Mark).

2)Ultra is a Venezuelan rock band founded en 1994 under the name of Inteligencia Bruta and then changed into Ultra.

3) Ultra is a hip-hop superduo consisting of NYC rappers Kool Keith and Tim Dog.

4) Ultra was a Hard Rock band from San Antonio, Texas from the mid- to late-1970s. Their sound was a mixture of heavy Southern blues rock, psychedelic rock, and proto-metal. The members were: Galen Niles (guitar), Larry McGuffin (guitar), Don Evans (vocals), Scott Stephens (bass), and Tom Schleuning (drums). All of the songs were written by Niles, McGuffin & Evans. Their recordings were compiled two decades later into the album "Ultra" by Monster Records in Texas.

5) Ultra (also recording as Rider) is also an English pop band, which was most successful in the late 1990s.

6) Ultra was a synth-pop band from Latvia that existed around the late 1990s, conceived as one more Latvian-language version of the locally wildly popular Depeche Mode. Obviously taking their name from that group's 1997 album Ultra.

7) Ultra was an alias of Michael Phadt & Ullrich Brenner, who released three trance singles under the name from 2000-2001, "Free", "Let Freedom Reign", and "Lost in Time and Space"

8) Ultra is an anarcho-punk band from Barcelona. The band is made up of half ABSURDO and half ANARQUIA VERTICAL members. Their debut EP is pure fire, idealistic hardcore with venom and punch. Sonically clashing the golden years of Spanish or Italian hardcore with early NYHC and even Midwest hardcore while lyrically carrying the torch of anarchist Barcelona bands. Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.