Computer Applications In Music Frank Markovich Fall 2004 Revision A
A to D and D to A • These will be critical for you to understand with digital audio. • Will only cover the basics. • The world in Analog not digital but we do mainly digital recording now. • We take an analog signal and convert it to a digital signal. This is called A to D conversion.
The 2 important numbers • Number of bits, early recordings were only 8 bits, then the industry went to 16, now 24 bits is standard and 96 is even getting to be common with other’s inbetween. • Sampling rate – how many conversions per second. The higher the sampling rate the higher the accuracy of the conversion. Typically in music it is 44KHz, 48KHz, or 96KHz. Less than 44KHz (32KHz is reserved for mainly voice – lecture etc.). Nyquest says that the frequency must be at least 2 times the highest frequency of interest to capture the information. Since the human ear can hear up to 20KHz – well some can, that means that the sampling rate must be over that frequence. • I will show on the board the idea of this.
D to A • Going back the other way you must convert from digital back to analog. • Same concepts apply and your D to A must match frequency and sample size in order to work properly.
Recording • I just want to give you an introduction into digital recording. We will first review the A/D and D/A. • I will do this with equipment in our lab to start but will bring in ProTools at a later date. • To start we will use sound forge. We will start on Page 6 of the online manual.
Sound forge advantages • Easy to get started. • With an external mixer can do quite a bit. • Good method to learn the basics, very little equipment required etc. • I use this for simple things – lectures etc. • Very fast and easy to learn. Once you have learned this other programs will fall into place. • Good for just scratchpad or for a small demo. If you need something fast this works well.
Sound forge disadvantages • Only 2 channels. For most recording this is just not enough. - I use at least 2 just per instrument. • Not full featured in the version we are running. I really prefer to use ProTools for critical work. • Some small bugs that are bothersome. • Not in a format that studios can mix down to easily. • Lower dynamic range than external systems. • No automation in the version – new version may offer it with an external Mackie Mixer.
Mackie Mixer • Manual is loaded on your computer at school. Be sure to read it then play with the mixer. • Also review the hook up manual. • At this point will go to word document on basic mixing.
Software Mixers • In order to really take advantage of these you must know the basics of mixing. • The idea is just the same as a H/W mixer. • Following is a 2 page on one S/W mixer. • I like Vegas as a stand alone mixer but it may be overkill for you.
Do a write-up of each section – at least a couple of sentences summing up the section. Add in any questions that you may have on this.
MIDI, which means: • Musical Instrument Digital Interface, • is a digital communications protocol. In August of 1983, music manufacturers agreed on a document that is called "MIDI 1.0 Specification". Any device that has MIDI capabilities must adhere to this specific data structure to ensure that all MIDI devices are capable of working together. This protocol is a language that allows interworking between instruments from different manufacturers by providing a link that is capable of transmitting and receiving digital data. It is important to remember that MIDI transmits commands, but it does not transmit an audio signal. The MIDI specification includes a common language that provides information about events, such as note on and off, preset changes, sustain pedal, pitch bend, and timing information. The specification has been updated more recently with specific data structures for handling sample dumps, MIDI time code, general MIDI and standard MIDI files. To see a complete listing of all MIDI data, go to:
There are four main categories of MIDI data. The following charts represent information on the current hexadecimal numbers that are used in MIDI transmission. Each MIDI message includes a Status Byte. If they are required, Data Bytes will follow each Status Byte. Some of the example below have links that may be clicked for more detail about the MIDI event.
MIDI at NDNU COLLEGE OF NOTRE DAME MUSIC TECHNOLOGY LABORATORY MIDI AND MUSIC SYNTHESIZERS This handout presents instructions for using General MIDI specifications with each of the three music keyboard synthesizers in the Music Tech Lab. If you need more details than are in this handout, consult the published manuals at the computer stations.
Start up Finale In the Help choose “How to use the manual”
After reading how to use the manual go to help and read Chapters 1-3 • in the manual. • Do a paper for assignment 6 on how you will use Finale or a notation • program in your music development. • Answer the following questions: • Why use the computer to notate? • What advantages does the computer have in doing notation? • What could be future uses for the computer in notation? • How will you use the computer and notation? • What roadblocks do you see to learning how to notate on the computer? • This should be turned in by Oct 11, 2004
2) Which website that have lots of MIDI files to download? How to put a MIDI on my web page? What is the difference between MIDI and MP3? Let’s start by answering these questions: MP3 files are audio files that have been compressed. The compression takes the audio files and makes them smaller with some minor loss of information. Digital data (16 bits) is in the original Wave file. This is at 44KHz with 16 bits. That data would normally be run through a DAC (Digital to Analog Converter) and converted into an analog signal to drive the speakers. With MP3 the data is compressed and on playback it uncompressed but is still handled in a similar matter. A 3 minute MP3 would have about 4Meg of information. MIDI files are computer files that are MIDI data. No music until it goes through a MIDI instrument and the digital data is then read to control the instrument and make the music. A 3 minute MIDI file would have about 1K of data. Much smaller and easier to handle.