Question: Barcelona is the second solo album recorded by a singer known for his four-octave what?
Context: Barcelona is the second solo album recorded by Freddie Mercury, frontman of popular British rock band Queen, and operatic soprano Montserrat Caballé.  Released in 1988.  It is the second and final solo album recorded by Mercury. Ronnie Lane's Slim Chance is the second solo album recorded by Ronnie Lane, one of the founders of Small Faces and Faces, after he left Faces to live on a farm in Wales.  In homage to his perceived chances of commercial success, he named his band Slim Chance.  Six of the thirteen songs on this album were written by Lane, the rest of Slim Chance, and Kate Lambert, his wife; the remainder were cover versions.  Haunting, profound, and witty, the album did not exceed his commercial expectations. In the Now is the second solo album by British singer-songwriter Barry Gibb, released on 7 October 2016 by Columbia Records.  Although his second solo album (since 1984's "Now Voyager"), it is the first of all new material since the Bee Gees' final studio album "This Is Where I Came In" (2001).  Gibb said of the album: "This is a dream come true for me.  It's a new chapter in my life.  I always hoped one day that The Bee Gees would be with Columbia or indeed Sony so, it's a great joy for me to start again this way with such great people." Omari Ishmael Grandberry (born November 12, 1984, known by his stage name Omarion) is an American singer, songwriter, rapper, actor and dancer.  He is best known as being the lead singer of the American R&B boy band B2K; the group achieved success with singles like "Bump, Bump, Bump", "Uh Huh", and "Girlfriend", which all reached success on the "Billboard" Hot 100.  After the group's disbandment, Omarion released his debut solo album, "O" (2005), which debuted atop the "Billboard" 200 and received a Grammy Award nomination for Best Contemporary R&B Album at the 48th Grammy Awards.  His second solo album, "21" (2006), contained his second highest-charting single to date, "Ice Box", which reached the top 20 on the "Billboard" Hot 100.  His third solo album, "Ollusion" (2010), was released on January 12, 2010, with the lead single, "I Get It In".  His fourth solo album, "Sex Playlist" (2014), spawned the single, "Post to Be", which was certified 3x platinum and reached number 13 on the Hot 100 chart in May 2015, and became his highest charting single to date. The Saga Continues is the second solo album recorded by funk musician Roger Troutman, released in 1984 on the Warner Bros. label.  The album contains Troutman's cover of Wilson Pickett's "In the Midnight Hour", which reached #34 on the U.S. R&B chart, as well as hits "In the Mix" and "Girl Cut It Out", a duet with Wanda Rash.  Like his previous solo offering, "The Many Facets of Roger", Troutman and his band mates from Zapp, including brothers Lester, Larry and Terry, helped contribute to the album. Tasty is the second solo album released by recording artist Patti LaBelle, her second solo album with Epic Records.  Compared to the success of her debut album, released the previous year, the album performed only modestly well but featured the popular tunes "Eyes in the Back of My Head", which became a club hit, the Latin soul flavored "Teach Me Tonight (Me Gusta Tu Baile)", the David Lasley composition "I See Home" (later covered a year later by Tina Turner) and the ballad "Little Girls".  "Eyes in the Back of My Head" became an international hit reaching the top five of the Italian singles chart.  The album also featured covers of songs by Boz Scaggs, The Drifters and Roy Hamilton in addition to a couple songs co-written by LaBelle herself, including "Teach Me Tonight" and "Quiet Time". Farrokh "Freddie" Mercury (born Bulsara; 5 September 1946 – 24 November 1991) was a British singer, songwriter and record producer, known as the lead vocalist of the rock band Queen.  He was known for his flamboyant stage persona and four-octave vocal range.  Mercury wrote numerous hits for Queen, including "Bohemian Rhapsody", "Killer Queen", "Somebody to Love", "Don't Stop Me Now", "Crazy Little Thing Called Love", and "We Are the Champions".  He led a solo career while performing with Queen, and occasionally served as a producer and guest musician for other artists. Arthur Maia is the second solo album recorded by the Brazilian bass player Arthur Maia.  The album is also known as "Sonora", which is the first song of it, and was well criticized by professionals around the world. Anita Lipnicka (born June 13, 1975 in Piotrków Trybunalski) is a Polish singer and songwriter.  Her career as a singer started with Varius Manx, a band she joined in 1993.  In 1996, she made a decision to pursue a solo career, she left the band and moved to London where she made her first solo album.  The album was called "Wszystko się może zdarzyć" (Everything Can Happen) and was a huge success.  In 1998 Lipnicka released her second solo album "To, co naprawdę" (What Is Real).  In 2000, her third solo album appeared-"Moje oczy sa zielone" (My eyes are green).  In 2001, Lipnicka started to work with John Porter.  Together they recorded two albums, "Nieprzyzwoite piosenki" (Indecent Songs) in 2003 and "Inside Story" in 2005.  Both albums were all in English.  The album "Indecent Songs" won The Fryderyk award for "The Pop Album of the Year." The discography of Propaganda (birth name Jason Emmanuel Petty), an American Christian hip hop and spoken word artist and poet from Los Angeles, California, consists of five studio albums, two EPs, twelve compilation appearances, eleven music videos, including one as a featured performer, and twenty-three guest appearances.  Discovered by the underground hip hop collective Tunnel Rats, Petty made his debut in 2002 on "Speak Life" by Sev Statik.  On April 8, 2003, he released his solo debut album, "Out of Knowhere", with UpRok Records, and recorded as part of the Tunnel Rats on "".  He then recorded with the Tunnel Rats for the collective's 2004 self-titled album.  In 2006 he released the "I Am Not Them EP" with Tunnel Rat Music and recorded "Live This" as part of the Tunnel Rats-affiliated group Footsoldiers.  Footsoldiers also collaborated with KRS-One on his album "Life", with Petty appearing on the song "I Ain't Leaving", and DJ Tony Touch released a mixtape featuring the group.  Petty released a second solo EP, "The Sketchbook: A Small Collection of Unreleased Material", independently in 2008, and his second album, "Listen Watch Focus", also came out in 2008 through End of Earth Records.  Petty's next three albums were all released through the Portland-based Humble Beast Records.  The first, entitled "Art Ambidextrous", was recorded in collaboration with Odd Thomas, and came out in 2011.  Petty's third solo album, "Excellent", came out in 2012, and charted at No. 7 on the "Billboard" Top Gospel chart.  Petty's fourth solo album, "Crimson Cord" came out on April 29, 2014, and charted at No. 5 on the Billboard Top Christian chart, No. 2 on the Top Gospel, and No. 8 on the Top Rap chart.
Answer: vocal range