2017 Orchestral arrangements for Hildur Guðnadóttir's and Jóhann Jóhannsson'smusical score of Garth Davis's film Mary Magdalene (premiere in 2018).
2017 Orchestral arrangements for Hildur Guðnadóttir's musical score of Stefano Sollima's film Soldado (premiere in 2018).
2017 String arrangements for Högni Egilsson on his album Two Trains. (Played and recorded by Viktor)
2017 String arrangements for Ragnar Ólafsson on his album Urges. (Played and recorded by Viktor)
2017 String arrangements for Jóhann Jóhannsson's rework of Ryuichi Sakamoto's Solari. (Played and recorded by Viktor)
2016 Arrangements for Emilíana Torrini and the Iceland Symphony Orchestra.
2015 Arrangements for a whole concert with a 15 piece ensemble playing Ólafur Arnalds' music for a concert in the Sydney Opera House.
2015 String arrangements on the song Hunger from the album Beneath the skin by Of Monsters and Men. (Played and recorded by Viktor)
2015 String arrangements for Barði Jóhannsson from Bang Gang on his newly released album The Wolves Are Whispering. (Played and recorded by Viktor)
2014 Arrangements of pieces by Karl Sighvatsson for Karlsvaka concert in Eldborg, Harpa Concert House. The program was as following:
2014 Helgi Björnsson. Ég fer á landrover frá Mývatni á Kópasker. Arrangements for 2 flutes and 3 clarinets.
2014 Uni Stefson. String arrangements, string recording and performing for the song Enginn grætur of Uni Stefson.
2014 Arrangements for Hanna Mia Brekkan a rhythmical band, violin, cello, clarinet and piano for a CD that I recorded, produced and mixed. The CD will be released later this year.
2013 Arrangements of Nils Bech (NO) for Nils and SKARK ensemble. Premiered in Harpefoss, Norway.
2013 String arrangements for President bongo for his new album Serengeti. (Played and recorded by Viktor)
2013 Songs by Ólafur Arnalds arranged for chamber orchestra. Played f.ex. in Volksbühne Berlin and in New York Live on NPR under the direction of Viktor Orri Árnason.
2013 Happy. Pharrell Williams's song arranged for 2 trumpets, horn, trombone, tuba and percussion. Played in Berlin by hauptstadtBLECH.
2013 Atmospheric string texture arrangements for Ólafur Arnalds in the making of the music for Broadchurch. The orignial music won the BAFTA price for the best original music in TV-series.
2013 Arrangement for a full symphony orcehstra of Jónas Sigurðsson's song Hafið er svart at the “Söngvaskáldin og Sinfó” concert the 30th of may, 2013.
2010 Alpanon. The DVD release of Hjaltalín.
2016 Var, for a Male choir, ensemble and electronics. Written for Karlakórinn Fóstbræður on their 100th anniversary.
2015 Nocturne for Viola and its difference tones.
2014 VIVID (55 min). A dance piece commissioned by Unnur Elísabet Gunnarsdóttir. Premiered at The National Theatre of Iceland.
2014 Hljóðprufa for 33 loudspeakers (12 Min). Electronic piece based on 3 different recordings of Hljóðprufa (2011). Premiered at Hochscule für Musik Hanns Eisler.
2014 Turyia. A collaboration between Högni Egilsson and Viktor Orri Árnason for the Hallgrímskirkja church bells.
2013 Vögguvísa fyrir fiðlu (4 min). Solo piece for violin, premiered by Hulda Jónsdóttir the 30th of July in Sigurjónssafn, Reykjavík Iceland.
2013 …Trans (16 min) for quintet. Dedicated to Jóhann Már Nardeau for his graduation from the Conservatoire Superieur Paris. The first two episodes were recorded for his graduation project. The work was performed in full length at the Hanns Eisler Preis, Viktor Orri won 3rd prize with his group on performing the piece.
2013 Tilbrigði fyrir strengjasveit (10 min). Performed by SKARK ensemble in Salurinn in Kópavogur under the direction of Viktor Orri.
2013 Septett - Performed at Klangwerkstatt in Berlin under the direction of Helmut Zapf.
2013 Recomposed Arias, with original melody. Premiered in Hanns Eisler Hochschule für Musik.
G.F.Händel: Piangero la sorte mia (7 min)
G.F. Händel: Where shall I fly (6 min)
Giacomo Carrissimi: Vittore mio core (4 min)
2012 Hljóðprufa for 3 string quartets (14 min). The piece Hljóðprufa (2011) was recomposed for 3 string quartets and played by SKARK ensemble in the garage of Harpa concert hall, and again in the Studio of Ólafur Elíasson in Berlín and in Harpefoss, Norway.
2012 Variationen für Klavier (10 min). Premiered by Bjarni Frímann Bjarnason in the Hanns Eisler Preis. Viktor Orri got the 3rd price in the competition.
2011 Dreams (9 min), for a full modern Orchestra (80 piece). The piece was chosen to be played at the UNM festival in Iceland but but it proved to be too large-scale for the occasion.
2011 Hljóðprufa (12 min), for a string quartet. Premiered at Podium Festival in Stokkalækur by Eygló Dóra Davíðsdóttir 1. violin, Magnus Boye Hansen 2. violin, Joachim Kelber viola and Adam Krzeszowiec cello. The piece was played again at the UNM festival in Iceland in 2012 by Strokkvartettinn Siggi.
2011 Triosatz (8 min). Premiered in Universität der Künste in Berlin by Bjarni Frímann Bjarnason electric keyboard, Anne Yumino Weber cello and Anika Weichelt clarinet.
2010 Hugleiðing (6 min). Composed for a young string orchestra from Tónskóli Sigursveins, dedicated to Helga Þórarinsdóttir. Also played by SKARK ensemble at Þjóðmenningarhúsið.
2010 Overture - played by the Icelandic Symphony Orchestra at Hjaltalín's - Alpanon concert.
2010 Frá myrkri til ljóss. Composed for the Festival of Sacred Arts in Iceland. A piece for clarinet, horn, trumpet, trombone, percussion and churchbells of Hallgrímskirkja. Performed in the tower of Hallgrímskirkja under the direction of Viktor Orri.
2009 Verk fyrir tvo. A duet for 2 violins and 2 violas, performed by 2 players only. 1 of each instrument is a scorda tura (detuned instrument). Dedicated to Bjarni Frímann Bjarnason and performed by Bjarni and Viktor at Bjarni's graduation from the Iceland Academy of the Arts in Salurinn, Kópavogur.
2009 Verk fyrir hljómsveit. Premiered in Ísafjörður at the Við Djúpið festival. The piece was broadcasted a couple of times on RÚV (The Icelandic national broadcasting service). The piece was performed for the 2nd time by the finnish ensemble Avanti at the UNM festival in 2010 under the direction of Jani Telaranta.
2006 Sinfonía nr. 1. Premiere took place at Reykjavík arts festival in 2009. Performed by with Ísafold ensemble and Hjaltalín.