Question:
Royksopp (Norwegian pronunciation: ['royksop]) are a Norwegian electronic music duo from Tromso, formed in 1998. The duo consists of Svein Berge and Torbjorn Brundtland. Royksopp is the Norwegian word for the class of mushrooms known as puffballs, the band's name substitutes o in place of o. Berge and Brundtland were introduced to each other through a mutual friend in Tromso, Norway. They enjoyed the same films and music, and shared an interest in electronics.
Royksopp's third studio album, Junior, was released on 23 March 2009, featuring the single "Happy Up Here". The song debuted on BBC Radio 1's Pete Tong show on 9 January 2009. It was officially released digitally on 16 March 2009. The music video for "Happy Up Here", made by Reuben Sutherland, features elements from the arcade game Space Invaders. Both the single and the video were met with positive reactions from the press and fans.  "The Girl and the Robot", the second single from the album Junior, featuring vocals from Swedish singer Robyn, was released on 15 June 2009. The vinyl and digital versions of the single included remixes of the song by Kris Menace, Chateau Marmont and Spencer & Hill. At the 52nd Grammy Awards, the Jean Elan remix of "The Girl and the Robot" was nominated for Best Remixed Recording, Non-Classical. "This Must Be It" is the third single from the album, including vocals from Swedish singer Karin Dreijer Andersson of The Knife and Fever Ray. The single also featuring remixes by Thin White Duke, LehtMoJoe, Rex the Dog and Apparat, among others. The band later released the stems for the song "Tricky Tricky" as part of a remix competition and the winning entries were released on 27 October 2009.  Junior was a success around the world. The album peaked at number one in Norway, the band's third consecutive release to do so. Junior also peaked at number 21 on the UK Albums Chart and charted on many Billboard charts, including the Billboard 200-the first Royksopp release to do so-where it peaked at number 126. The album also peaked at number four on the Top Electronic Albums chart and number two on the Top Heatseekers chart.  Junior was followed by Senior, which is more quiet, "withdrawn and introspective" and "create[s] an atmosphere and an ambiance". Senior is the duo's first album to consist solely of instrumental tracks. The first single from the album, "The Drug", was released on 9 August 2010. The album itself was released on 13 September 2010, and was successful in the band's native Norway, peaking at number one, the band's fourth consecutive release to do so.
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What kind of instrumental tracks or name one?

Answer:
Junior was followed by Senior, which is more quiet, "withdrawn and introspective" and "create[s] an atmosphere and an ambiance".

Answer the question at the end by quoting:

Jeremy Webster "Fred" Frith (born 17 February 1949) is an English multi-instrumentalist, composer, and improvisor. Probably best known for his guitar work, Frith first came to attention as one of the founding members of the English avant-rock group Henry Cow. He was also a member of the groups Art Bears, Massacre, and Skeleton Crew. He has collaborated with a number of prominent musicians, including Robert Wyatt, Derek Bailey, the Residents, Lol Coxhill, John Zorn, Brian Eno, Mike Patton, Lars Hollmer, Bill Laswell, Iva Bittova, Jad Fair, Kramer, the ARTE Quartett, and Bob Ostertag.
Fred Frith has used a number of different guitars, including homemade instruments, over the years, depending on the type of music he is playing. For the more structured and refined music he has often used a Gibson ES-345, for example on his solo album, Gravity. For the heavier "rock" sound, as in Massacre, he has used an old 1961 solid body Burns guitar, created by the British craftsman Jim Burns. On his landmark Guitar Solos album, Frith used a modified 1936 Gibson K-11 guitar (q.v. for details).  For Frith's early unstructured music, as with Henry Kaiser on With Friends Like These, and his early table-top guitar solo performances, he used a homemade six- and eight-string double-neck guitar created by a friend, Charles Fletcher. Frith told DownBeat magazine in 1983: "It was the one and only guitar that he ever built ... he constructed it mainly out of old pieces from other guitars that I had, and for the body I think he used an old door." The possibilities offered by homemade instruments prompted Frith to start creating his own guitars, basically slabs of wood on which he mounted a pickup, a bridge, and strings stretched over metal screws. "The basic design of the instrument is supposed to be as rudimentary and flexible as possible," Frith said, "so I can use an electric drill to bore holes into the body of it to achieve certain sounds ... ."  Frith uses a variety of implements to play guitar, from traditional guitar picks to violin bows, drum sticks, egg beaters, paint brushes, lengths of metal chain, and other found objects. Frith remarked: "It's more to do with my interest in found objects and the use of certain kinds of textures which have an effect on the string ... the difference between the touch of stone, the touch of glass, the touch of wood, the touch of paper - those kinds of basic elements that you're using against the surface of the strings which produce different sounds."  In a typical solo improvising concert, Frith would lay a couple of his homemade guitars flat on a table and play them with a collection of found objects (varying from concert to concert). He would drop objects, like ball bearings, dried beans, and rice on the strings while stroking, scraping, and hitting them with whatever was on hand. Later he added a live sampler to his on-stage equipment, which he controlled with pedals. The sampler enabled him to dynamically capture and loop guitar sounds, over which he would capture and loop new sounds, and so on, until he had a bed of repeated patterns on top of which he would then begin his solo performance.

Was there anything interesting about there playing technique?
Frith uses a variety of implements to play guitar, from traditional guitar picks to violin bows, drum sticks, egg beaters, paint brushes, lengths of metal chain, and other found objects.