Although his music for the 2005 series of "Doctor Who" relied largely on sampled sounds, his later arrangements for the show, beginning with "The Christmas Invasion," have been more orchestral, often being recorded by the BBC National Orchestra of Wales, supplemented by vocal performances with Melanie Pappenheim and others. One of the most well-known orchestral numbers is 'Abigail's Song', sung by Katherine Jenkins, from the 2010 Christmas special "A Christmas Carol", was released in March 2011. The orchestral scoring (partly reflecting a larger budget) contrasts strongly with music for the classic 1963-1989 series of "Doctor Who", as produced by the BBC Radiophonic Workshop, Mark Ayres "et al.", which generally had an electronic feel, with innovative instrumentation.