Question: Are Davey Havok and Timo Kotipelto lead vocalists?

full_context: Document 1: Tuomo Lassila: Tuomo Lassila (born 1965) is a Finnish musician best known as the former drummer, founder member and co-songwriter of the power metal band Stratovarius and currently the drummer and percussionist for the Finnish metal band Conquest.
Document 2: Markus Toivonen: Markus Toivonen (born 1979 in Helsinki) is the founding member of the Finnish folk/death metal band Ensiferum. Markus founded the band in 1995 and is the sole original member to have lasted the distance to Ensiferum's present incarnation. His role in the band is guitarist and primary songwriter. He has always contributed backing vocals and since the departure of Jari Mäenpää in 2004 has taken up a greater role behind the microphone, sharing the clean vocal parts with new bass player Sami Hinkka, with Mäenpää's replacement Petri Lindroos handling the harsh vocals.
Document 3: Blackoustic: Blackoustic is a collaborative acoustic album by Stratovarius and Cain's Offering vocalist Timo Kotipelto and ex-Sonata Arctica and Cain's Offering guitarist Jani Liimatainen (credited as Kotipelto & Liimatainen). The album was released on October 19, 2012, and entered the Finnish charts at #13 the first week. The album is self-financed. While initially only sold during performances, the album was eventually released through the Earmusic label, which had released the prior Stratovarius albums since "Polaris".
Document 4: Fourth Dimension (Stratovarius album): Fourth Dimension is the fourth studio album by power metal band Stratovarius, released on 11 April 1995 through Noise Records. The album is the band's first to feature vocalist Timo Kotipelto as well as the last with keyboardist Antti Ikonen and drummer Tuomo Lassila, thus being the last Stratovarius album to date featuring an all-Finnish line-up. Founding member and guitarist Timo Tolkki, who had served as the band's vocalist for their first three albums, still provided background vocals on "Fourth Dimension" before handing over lead singing duties to Kotipelto for all subsequent albums.
Document 5: David Draiman: David Michael Draiman (born March 13, 1973) is an American songwriter and the vocalist for the band Disturbed as well as for the band Device. Draiman is known for his distorted voice and percussive singing style. In November 2006, Draiman was voted number 42 on the "Hit Parader"’s ""Top 100 Metal Vocalists of All Time"". Draiman has written some of Disturbed's most successful singles, such as "Stupify", "Down with the Sickness", "Indestructible", and "Inside the Fire".
Document 6: Dreamspace: Dreamspace is the third studio album by power metal band Stratovarius, released on 9 February 1994 through Noise Records. It is the last Stratovarius album to feature guitarist Timo Tolkki on vocals (after which Timo Kotipelto became the lead singer on 1995's "Fourth Dimension"), as well as the first to feature bassist Jari Kainulainen.
Document 7: XTRMST: XTRMST is an American straight edge hardcore band featuring Davey Havok and Jade Puget of AFI. XTRMST is Havok and Puget's second side project after their electronic project Blaqk Audio. They released their debut album "XTRMST" in 2014 on long-time friend Steve Aoki's Dim Mak Records. Havok and Puget later added Chris Sorenson (Saosin) on bass, Josh James (Stick to Your Guns, Evergreen Terrace), Casey Jones on guitar, and Val Saucedo (Loma Prieta, Punch) on drums.
Document 8: Timo Kotipelto: Timo Antero Kotipelto (born 15 March 1969 in Lappajärvi, Finland) is the vocalist of the Finnish power metal band Stratovarius and is the creator and vocalist of the power metal band Kotipelto. Kotipelto is currently the longest standing member of Stratovarius, after the departure of Timo Tolkki.
Document 9: Kotipelto: Kotipelto is a Finnish melodic power metal self-named band by Timo Kotipelto created during a hiatus in activity for power metal band Stratovarius. Kotipelto has been commercially well received in their native Finland, with a Top 10 single "Beginning" from his first release "Waiting for the Dawn", and lyrics often concentrating on ancient Egyptian themes.
Document 10: Jani Liimatainen: Jani Allan Kristian Liimatainen (born 9 September 1980 in Kemi, Finland) is a Finnish musician, songwriter and backing vocalist. He is the former guitarist and one of the founding members of the power metal band Sonata Arctica. He has also performed with Cain's Offering, Altaria and Stratovarius vocalist Timo Kotipelto (his band mate in Cain's Offering).
Document 11: David Vanian: Dave Vanian (born David Lett, 12 October 1956) is a rock musician and lead singer of the punk rock band The Damned. Formed in 1976 in London, The Damned were the first British punk band to release a single, an album, have a record hit the UK charts, and tour the United States. With a fluid line-up since their founding, Vanian has been the only ever-present member.
Document 12: Dave Gahan: David "Dave" Gahan ( ; born David Callcott; 9 May 1962) is an English singer-songwriter, best known as the baritone lead singer of the electronic band Depeche Mode since their debut in 1980. He is also an accomplished solo artist, releasing albums in 2003 ("Paper Monsters") and 2007 ("Hourglass").
Document 13: AFI (band): AFI (abbreviation for A Fire Inside) is an American rock band from Ukiah, California, formed in 1991. They have had the same lineup since 1998: lead vocalist Davey Havok, drummer and backup vocalist Adam Carson, with bassist Hunter Burgan and guitarist Jade Puget, who both play keyboard and contribute backup vocals. Of the current lineup, Havok and Carson are the two remaining original members.
Document 14: Material (Blaqk Audio album): Material is the third studio album by American electronica band Blaqk Audio, consisting of Davey Havok and Jade Puget of AFI. it was released on April 15, 2016 under Blaqknoise/Kobalt Records. The first single from the album, "Anointed", was released on January 26 for streaming through SoundCloud and through digital retailers on February 19.
Document 15: Davey Havok: David Paden Marchand (born November 20, 1975), known professionally as Davey Havok, is the lead vocalist of the American rock band AFI, the electronic music band Blaqk Audio, hardcore band XTRMST, and new wave band Dreamcar.
ground_truth: yes