Somewhat akin to Brahms, Holmboe attempted a considerable number of string quartets before completing what is now officially his first. Once that hurdle was overcome, however, he wrote quartets throughout the rest of his life, and was working on one when he died. The recorded works are as follows:
- String Quartet No.1, op.46 (M.159)
- String Quartet No.2, op.47 (M.161)
- String Quartet No.3, op.48 (M.165)
- String Quartet No.4, op.63 (M.183)
- String Quartet No.5, op.66 (M.188)
- String Quartet No.6, op.78 (M.210)
- String Quartet No.7, op.86 (M.224)
- String Quartet No.8, op.87 (M.225)
- String Quartet No.9, op.92 (M.228)
- String Quartet No.10, op.102 (M.243)
- String Quartet No.11 'Quartetto Rustico', op.111 (M.262)
- String Quartet No.12, op.116 (M.269)
- String Quartet No.13, op.124 (M.277)
- String Quartet No.14, op.125 (M.278)
- String Quartet No.15, op.135 (M.291)
- String Quartet No.16, op.146 (M.306)
- String Quartet No.17 'Mattinata' (Morning), op.152 (M.312)
- String Quartet No.18 'Giornata' (Daytime), op.153 (M.314)
- String Quartet No.19 'Serata' (Evening), op.156 (M.313)
- String Quartet No.20 'Notturno' (Nighttime), op.160 (M.322)
- Sværm (Swarm), string quartet version, op.190b (M.360)
- Quartetto Sereno, op.197 (posth.) completed by Per Nørgård
Kontra Quartet recordings
There is only one complete set of the quartets, performed by the Kontra Quartet (Da Capo
8.207001).
The separate volumes are often still available and may even still be cheaper in some formats (at least some download stores appear to have failed to pass on the sharp discounting of the CD edition of the box set).
- Volume 1: Quartets 1, 3 and 4 (Da Capo DCCD 9203)
- Volume 2: Quartets 2, 5 and 6 (Da Capo 8.224026)
- Volume 3: Quartets 7, 8 and 9 (Da Capo 8.224073)
- Volume 4: Quartets 10, 11 and 12 (Da Capo 8.224101)
- Volume 5: Quartets 13, 14 and 15 (Da Capo 8.224127)
- Volume 6: Quartets 17, 19 and 20 (Da Capo
8.224128)
- Volume 7: Quartets 16 and 18, Sværm and Quartetto Sereno (Da Capo 8.224131)
The recording of String Quartet No.4 also appears on Da Capo's compilation from its Holmboe recordings,
The Key Masterpieces (Da Capo 8.226101-02), and one movement of the Quartetto Sereno appears on
Two Centuries of Danish Classical Music: An Anthology in Sound (Danish Music Information Centre MICD 4).
Copenhagen Quartet (Københavns Strygekvartet) recordings
The other major sequence of recordings is on LP by the Copenhagen String Quartet, who gave the premiere of most of the quartets from no.7 onwards. However, their recordings only cover quartets 1 to 10, 15 and 16, and it appears they have never been made available in a more modern format.
Quartets 1 and 4 were originally released in about 1963 (Fona LPK 538 and LPKS 538, mono and stereo respectively). At some point, quartets 7 and 8 were also released (Fona LPK 543), and quartet no.8 also appeared with Nielsen's 4th quartet (Turnabout TV 34217S).
Quartets 1 to 10 were then released in the early 1970s on a series of 5 LPs with similar covers as follows:
- Quartets 7 and 8 (Fona TF 108)
- Quartets 1 and 4 (Fona TF 109)
- Quartets 3 and 5 (Fona TF 110)
- Quartets 2 and 6 (Fona TF 111)
- Quartets 9 and 10 (Fona TF 133)

The recordings of quartets 1, 4, 7 and 8 appear to be the same as on the previous releases, but I am not certain of this. The recording of String Quartet No.1 was released again in the
Dansk Musik Antologi Series, coupled with two of Holmboe's choral works (EMI DMA 076).
The recordings of quartets 15 and 16 were released on an EMI disc that was part of the
Dansk Musik Antologi series (EMI 6C 065-39452 (DMA 048)).
Other recordings
As far as I'm aware, other recordings of the string quartets are only available on vinyl with one exception.
String Quartet No.1 was recorded by the Erling Bloch quartet, who premiered the work, on three 78 rpm discs (HMV DB 20137-39).
String Quartet No.2 was recorded in 1954 by the Musica-Vitalis Quartet (Decca LXT 5061/London LL 1078). It appeared with Nielsen's 2nd quartet (although it seems the London version has the spelling "Nielson"!).
In 2016 the recording was reissued by Forgotten Records (fr 1035), with the Nielsen quartet and also Nielsen's piano suite
Den Luciferiske.
String Quartets 3, 4 and 6 were all recorded by the Koppel Quartet, who had also premiered these three works. Quartet No.3, recorded in 1954, was coupled with Nielsen's 4th quartet (Decca LXT 5092/London LL 1119). This pair of recordings have been included in a 2015 box set called
DECCA SOUND - THE MONO YEARS 1944-1956 (Decca 4787946), making this the only performance other than the Kontra series that is definitely available in a more modern format.
Quartet No.4 was recorded in 1959 and coupled with a cello sonata by Hermann Koppel (the member of the quartet was Julius Koppel) on an LP called
Music at Louisiana (LRLP 3003)
Quartet no.6 was coupled with
Quartetto Brioso, op.21 by Per Nørgård (Wilhelm Hansen LPWH 3011).
Finally,
String Quartet No.11 was recorded by the Scandinavian String Quartet who also premiered the work. It was again coupled with Nielsen's 4th quartet (EMI 6E 061-38119).