The first two (of six) string quartets by George Macfarren (1813-1887) are now available to listen to or download as mp3 files on IMSLP:
http://imslp.org/wiki/String_Quartet_No.1_%28Macfarren,_Sir_George_Alexander%29 (http://imslp.org/wiki/String_Quartet_No.1_%28Macfarren,_Sir_George_Alexander%29)
http://imslp.org/wiki/String_Quartet_No.2,_Op.54_%28Macfarren,_Sir_George_Alexander%29 (http://imslp.org/wiki/String_Quartet_No.2,_Op.54_%28Macfarren,_Sir_George_Alexander%29)
These are amateur performances but are generally quite assured and and well worth a listen for those interested in the byways of Victorian music.
The third String Quartet (1842) has now also been added: http://imslp.org/wiki/String_Quartet_No.3_%28Macfarren,_Sir_George_Alexander%29 (http://imslp.org/wiki/String_Quartet_No.3_%28Macfarren,_Sir_George_Alexander%29)