1. Introduction

1.1. Project objective

This project aims to tackle the problem of how to recognise drum sounds in the context of music recordings.
In addition a software package is proposed, intended for recording studio use, that can categorise all drum hits within a rhythm played by a drummer. In so doing a digital recording of a rhythm can be split and categorised into its constituent drum parts and then 'played' by rhythms created by other drummers.
It is intended to use neural networks as the method of recognition and the main bulk of work within this report will be in how different types of network adapt to this task.

1.2. Impact of samplers on modern music

A "sampler" is the common term for any electronic musical instrument that can digitally  record sound from a wide variety of sources and reproduce the sound by means of a piano type keyboard or computer based sequencer. The first commercially available instrument of this kind was an Australian based product called the "Fairlight" produced in 1980. Since then, and owing to huge improvements in digital technology, many different types of sampler have become available. Accordingly, the use of samplers in modern music has grown rapidly since the mid eighties and their impact on various styles of music has been dramatic. One very popular use of the sampler has been to "sample" (record) bare drum rhythms from old recordings and to use these to form a rich juxtaposition with other modern musical instruments. Due to the drastically different recording techniques and philosophies used in recordings dating from the sixties and seventies, it was found that the sonic qualities of music and rhythms from these periods were virtually impossible to reproduce using modern studio equipment. Over the years literally thousands and thousands of these bare drum rhythms (which from here in will be referred to as break beats or breaks) have been discovered on increasingly diverse record collections, bringing a renewed popularity to forgotten records and also financial remuneration to writers and publishers.

1.3. Impact of computers in music production

Microprocessors have been used in electronic musical instruments from as early as the start of the seventies, however computers only began to show their musical colours in the early eighties. The most popular use of computers in those times (and still the most popular today) was to digitally control electronic instruments via an emergent interface known as MIDI (musical instrument digital interface). Whole songs could thus be arranged and played back in continuously editable format with little use of analogue tape. Software packages designed for this type of task are commonly known as a sequencers. In recent years it has been possible for complete multi-track hard disc recording systems to exist on a single PC or Mac. Producers and sound engineers have according built up vast libraries of sounds that include many break beats.