elaborate—their personalities come out and it's not my part anymore; they get into and give it that swing that I can't give it." Rodríguez-López took the additional step of recording the band member separately before layering the various tracks to create each song. Drummer Jon Theodore was the first to record his parts, and he spent time arranging and mapping out the songs with Omar and in the process figuring out what the rhythmic structures would be stated on the recording process. "This is the first time I've ever been so methodical about recording. Normally I would go into the situation with as good an idea as I could, whether that was from performing the songs on tour or having a general road map. But this was the first instance where I considered every single hit all the way through, every figure up to and including every change. There were no question marks. So when I was tracking with the metronome it was just a question of right or wrong." An exception of such recording method was the middle section of "Cassandra Gemini", edited from a lengthy jam session. Tracking this way had a mixed reception in the band; Theodore and bassist Juan Alderete responded well to the individualistic approach while keyboard player Isaiah "Ikey" Owens didn't like it at all. However, as Rodríguez-López stated, "People filling in ideas can become tedious and counterproductive. You find yourself working backwards. When you're in the studio 'what ifs' are your biggest enemy, so my general rule is, if it's something you can't live with—if a sentence begins with 'I can't' or 'I will not'—then we examine it. But if it's 'maybe we should' or 'I think that' then it's like, hey man, full steam ahead. Not that there isn't a lot of refinement to what we do—obviously there is— but I consider it a balance of raw energy and refinement." Frances the Mute featured the largest array of guest musicians on any Mars Volta album to date. Flea, who played bass on De-Loused in the Comatorium, this time contributed trumpet to "The Widow" and "Miranda...". "L'Via L'Viaquez" featured guitar solos from John Frusciante as well as Omar's childhood hero, salsa pianist Larry Harlow, while "Cassandra Gemini" had Adrián Terrazas-González (who eventually became a full-time member of the band) on woodwinds. All the tracks also included full string and horn sections, arranged by