Harry Halbreich is a Belgian musicologist.

He studied with Arthur Honegger

Arthur Honegger

Arthur Honegger was a Swiss composer, who was born in France and lived a large part of his life in Paris. He was a member of Les six. His most frequently performed work is probably the orchestral work Pacific 231, which is interpreted as imitating the sound of a steam locomotive.-Biography:Born...

 and later with Olivier Messiaen

Olivier Messiaen

Olivier Messiaen was a French composer, organist and ornithologist, one of the major composers of the 20th century. His music is rhythmically complex ; harmonically and melodically it is based on modes of limited transposition, which he abstracted from his early compositions and improvisations...

 at the Paris Conservatoire. From 1970 to 1976 he was Lecturer in Musical Analysis at the Royal Conservatory in Mons

Mons

Mons is a Walloon city and municipality located in the Belgian province of Hainaut, of which it is the capital. The Mons municipality includes the old communes of Cuesmes, Flénu, Ghlin, Hyon, Nimy, Obourg, Baudour , Jemappes, Ciply, Harmignies, Harveng, Havré, Maisières, Mesvin, Nouvelles,...

. He worked on numerous radio broadcasts and co-founded the Belgian music magazine Crescendo for which he has been major contributor.

He is known for a number of books, articles and studies on modern and contemporary music, including works on Messiaen, Claude Debussy

Claude Debussy

Claude-Achille Debussy was a French composer. Along with Maurice Ravel, he was one of the most prominent figures working within the field of impressionist music, though he himself intensely disliked the term when applied to his compositions...

, Arthur Honegger

Arthur Honegger

Arthur Honegger was a Swiss composer, who was born in France and lived a large part of his life in Paris. He was a member of Les six. His most frequently performed work is probably the orchestral work Pacific 231, which is interpreted as imitating the sound of a steam locomotive.-Biography:Born...

 and Bohuslav Martinů

Bohuslav Martinu

Bohuslav Martinů was a prolific Czech composer of modern classical music. He was of Czech and Rumanian ancestry. Martinů wrote six symphonies, 15 operas, 14 ballet scores and a large body of orchestral, chamber, vocal and instrumental works. Martinů became a violinist in the Czech Philharmonic...

. He has prepared musical catalogues of the works of Honegger and Martinů, and their works are therefore sometimes referred to by their H number. He assisted Nicolas Basri in orchestrating Honegger's opera

Opera

Opera is an art form in which singers and musicians perform a dramatic work combining text and musical score, usually in a theatrical setting. Opera incorporates many of the elements of spoken theatre, such as acting, scenery, and costumes and sometimes includes dance...

, La morte de Sainte Alméenne, originally written in 1918 for voice and piano; the new version was premiered in Utrecht

Utrecht (city)

Utrecht city and municipality is the capital and most populous city of the Dutch province of Utrecht. It is located in the eastern corner of the Randstad conurbation, and is the fourth largest city of the Netherlands with a population of 312,634 on 1 Jan 2011.Utrecht's ancient city centre features...

 on 26 November 2005, on the 50th anniversary of the composer's death.

Halbreich's interest in modern music has led to articles on composers including Iannis Xenakis

Iannis Xenakis

Iannis Xenakis was a Romanian-born Greek ethnic, naturalized French composer, music theorist, and architect-engineer. He is commonly recognized as one of the most important post-war avant-garde composers...

, Giacinto Scelsi

Giacinto Scelsi

Giacinto Scelsi , Count of Ayala Valva was an Italian composer who also wrote surrealist poetry in French....

, György Ligeti

György Ligeti

György Sándor Ligeti was a composer of contemporary classical music. Born in a Hungarian Jewish family in Transylvania, Romania, he briefly lived in Hungary before becoming an Austrian citizen.-Early life:...

, Edgard Varèse

Edgard Varèse

Edgard Victor Achille Charles Varèse, , whose name was also spelled Edgar Varèse , was an innovative French-born composer who spent the greater part of his career in the United States....

 and Maurice Ohana

Maurice Ohana

Maurice Ohana was an Anglo-French composer of Sephardic Jewish origin.Ohana was born in Casablanca, Morocco. He was a British citizen until 1976, as his father had been born in the British overseas territory of Gibraltar. He originally studied architecture, but abandoned this in favour of a...

. But he has also written on composers of the past including Johann Sebastian Bach

Johann Sebastian Bach

Johann Sebastian Bach was a German composer, organist, harpsichordist, violist, and violinist whose sacred and secular works for choir, orchestra, and solo instruments drew together the strands of the Baroque period and brought it to its ultimate maturity...

 and Ludwig van Beethoven

Ludwig van Beethoven

Ludwig van Beethoven was a German composer and pianist. A crucial figure in the transition between the Classical and Romantic eras in Western art music, he remains one of the most famous and influential composers of all time.Born in Bonn, then the capital of the Electorate of Cologne and part of...

.