About This Issue

This issue completes the pair of special issues guest-edited by Eric Lyon on the topic of high-density loudspeaker arrays (HDLAs). Whereas the previous issue (Vol. 40, No. 4, Winter 2016) focused mostly on institutions that house HDLAs for computer music, the present issue is directed toward questions of spatial perception and compositional practice. Two of the five articles present the results of psychoacoustic experimentation. Two others present composers' perspectives on their artistic creations for HDLAs. Another article offers an overview of spatial audio that touches on both perception and composition. Please refer to the Editor's Notes in the following pages to learn about Eric Lyon's perspectives on this issue's articles.

The letters to the editor in this issue build upon the forum of position statements on HDLAs that was found in the previous issue.

The current issue also includes program notes for the annual Sound Anthology (which in other years often also includes video). Normally, the anthology would have been presented in 2016, but it was postponed to coincide with this issue's articles, some of which were authored or coauthored by composers represented in the anthology. We are indebted to Eric Lyon for curating this collection of music written for HDLAs, which was recorded binaurally for presentation as stereo audio files intended for headphone listening. The files are available on MIT Press's Web site (http://www.mitpressjournals.org/toc/comj/41/1). Our thanks go to all the composers and sound engineers involved in this project. It represents the first time our annual anthology has consisted of binaural recordings, and we trust that listeners will find the headphone experience of these spatial compositions to be compelling.

Other material in this issue was gathered by the Journal's regular editorial staff. Spencer Salazar edited the Announcements and News sections, as usual. (Among other items, the Announcements describe an upcoming four-day festival of HDLA music and sound art.) Following Ross Feller's Reviews section, which reports on musical recordings, Margaret Cahill's Products of Interest section announces a good number of hardware audio interfaces and digital signal processing software plug-ins, as well as some digital audio workstation controllers, microphones, and other audio accessories.