[In "Slackline" for cello and piano by Pascal Dusapin] the two performers create an impressive sound space through movement in perfect synergy.
ResMusica, Michèle Tosi, 13/01/2020

In "Invece" for violoncello solo [by Pascal Dusapin] Anssi Karttunen combines passion and expressive gesture., Jérémie Bigorie, 13/01/2020

… six commentaries on English love poems [Hans Werner Henze - Englische Liebeslieder] teeming with a profusion of textures and colours. The Finnish cellist Anssi Karttunen could easily have got lost in the jungle, but I never mislaid his instrument’s trail — pure golden honey, sprightly and lyrical.
The Times, Oliver Knussen, 14/06/2019

The second cello concerto by Magnus Lindberg, with the excellent soloist Karttunen, is a masterpiece of balance; Karttunen doesn’t miss an opportunity in each movement to demonstrate his comprehensive ability., Michael Loos, 13/06/2016

For the soloist, the piece [Dutilleux’s …tout un monde lointain] is a virtuoso workout, with runs that span the instrument’s range, ghostly harmonics and an emphasis on the cello’s very highest range. He threw himself into an energetic, intense performance, handling all of the work’s technical challenges.
Miami Herald, David Flesher, 11/04/2016

Respite was provided by “Notes on light” for cello and orchestra, written by Finnish composer Kaija Saariaho. Anssi Karttunen displayed every possible playing technique of the cello with presence and confidence.
Saarbrücker Zeitung, 27/05/2014

…this is also brilliantly mature cello writing that takes full advantage of Karttunen's natural grace unruffled by even the most extreme virtuosic demands. Mainly, Lindberg exploits the cellist's mastery of nuance.
Los Angeles Times, Mark Swed, 20/10/2013

…Karttunen’s virtuosity and versatility are clearly on show, but so too is his shining, beautifully clean tone. A must for anyone curious to hear what 30 modern minds can subject a cello to.
The Strad, Edward Bhesania

Ms. Saariaho composed “Notes on Light,” an unconventional cello concerto, last year for the brilliant soloist here, the Finnish cellist Anssi Karttunen. (…) As always in a Saariaho score, color is primary, and Mr. Karttunen showed a mastery of myriad colorings in his rhapsodic performance.
The New York Times, 16/08/2008

The new 15-minute work has thick chords and delicate trills that seem to fill the air with heady, languid sensuality. Yet it still has power, and the virtuosity on display was arresting, given that Lindberg is a superb pianist and Karttunen perhaps the most impressive cellist on the scene today.
Los Angeles Times, 10/08/2006