## 2 Materials and Methods
### Details  
Eight different examples each of eight different classes of acoustic scene were recorded for a total of 64 recordings. All recordings are exactly 10 minutes in length. The uniform recording duration facilitates easy segmentation into clips of equal length (e.g., 20 segments, each 30 s long). Basic segmentation tools are available with the dataset in order to assist with this. The recordings were planned out specifically to create a completely evenly-weighted dataset between the various scenes and to facilitate easy partitioning into folds (e.g., six recordings used for training, the other two used for testing).  
The location classes were inspired by the classes featured in the TUT database: lakeside beach, bus, cafe/restaurant, car, city center, forest path, grocery store, home, library, metro station, office, urban park, residential area, train, and tram [25], but restricted to open public spaces, reflecting the shifted focus of this work towards acoustic scene analysis. The eight classes in EigenScape are as follows: Beach, Busy Street, Park, Pedestrian Zone, Quiet Street, Shopping Centre, Train Station, and Woodland. These location classes were chosen to give a good variety of acoustic environments found in urban areas and to be relatively accessible for the recording process. The recordings were made at locations across the North of England in May 2017. An online map has been created showing all the recording sites and is listed in Supplementary Materials. Basic location details are included in the dataset metadata, along with recording dates and times. Although individual consent is not required for recording in public spaces, permissions of the relevant local authorities or premises management was sought where possible. Some locations would not allow tripod-based recordings, so the microphone stand was held as a monopod. These are noted in the metadata.  
A little over 10 minutes was recorded at each location, with a short amount of time removed from the beginning and end of each file post-recording. This removed the experimenter noise incurred by activating and deactivating the equipment and achieved the exactly uniform length of the audio clips. During recording, every effort was made to minimise sound introduced to the scene by the experimenter or equipment. It should be noted that occasionally a curious passerby would ask about what was happening. This was fairly unavoidable in busier public places, but since conversation is part of the acoustic scenes of such locations, these incidents should not affect feature extraction too much. Discretion is advised if these recordings are used for listening tests or as background ambiences in sound design work.  
The complete dataset has been made available online for download. The full database is presented in uncompressed WAV format within a series of ZIP files organised by class. Since each recording is 10 minutes of 25 tracks at 24-bit/48 kHz, the whole set is just under 140 GB in size. As this could potentially be very taxing on disk space and problematic to download on slower internet connections, a second version of the dataset was created for easier access. This second version consists of all the recordings, but limited to the first-order Ambsonic channels (four tracks) and losslessly compressed to FLAC format within a single ZIP file. This results in a much more manageable size of 12.6 GB, whilst still enabling spatial audio analysis and reproduction. This is also in accordance with the UK Data Service's recommended format for audio data [34].