Whats MIDI ?
Midi stands for "Musical Instrument Digital Interface" it can be used for many different applications these days but its mainly used as the name suggests to connect a musical instrument like a keyboard to a computer. Other uses are....
1. for sequencing musical notes
2. for controlling equipment, even lighting not just audio related equipment
3. time code MTC.... MIDI TIME CODE
4. MMC .... MIDI MACHINE CODE. for remote contoller type applications. eg stop play rewind ff ect...
5. For updating the firmware on some equipment, eg Roland VS series.
How does MIDI Differ from Digital Audio ?
The easiest way to explain the difference is to say that MIDI is like Sheet music or score....Sheet music isn't music that u can hear but it tells a musicain how to play an instrument, MIDI is the HOW to play an instrument not the actual sound of an instrument. Digital Audio is the sound of an instrument that has already been played.
Both digital audio and MIDI are 0's and 1's however DA is recording/sampling the analog wave form and must sample it at 11kHz miniumum to give u an intelligable sound of the human voice. MIDI on the other hand is only recording which note is played, how long it was played, how hard it was played ect.... This is the basics, MIDI does record a lot more info than just that including aftertouch ect... But to keep it simple I will use this following example.
When you push a key on a midi keyboard the note (C3 for middle C) is sent out the midi port, when u release that key on the keyboard another MIDI message is sent saying that the key is no longer being held down. If you record only the note on message and not the note off message then when you play back the midi through a sound module the sound will continue on forever unless the sound has a decay time set as default. The way to stop this hanging note is by sending what is called a "full panic" which is a string of all midi note off messages one after the other.
How do u burn MIDI to a CD ??? You cant burn midi directly to a CD becuase its like putting sheet music into your Cd player.If you ever burn a midi file to a cd then u will get a sound similar to a Dialup Modem connecting. As far as a CD player is concerned those 0's and 1's are just random numbers.
How do u turn MIDI to Audio / WAV ?? if u have a firm grasp on what midi is and how it produces a sound then u should be able to work it out by thinking logically. I will explain what happens when u play a midi sequence then how to turn midi into audio. When u push play in your favourite sequencing program then the midi is sent to a midi driver which can then send it to either a midi out port or to a internal mid sound modual that is located in a chip on your sound card. The ADSP24 range of cards are AUDIO cards not SOUND cards that is why there is no midi synth on board and also why the card is capable of very high quaity recordings. If your midi is sent out a midi port then to hear the midi a sound modual is needed to be connected up to that port. The sound modual then turns the note information of the MIDI into audio via samples that are in the modual. To get the Audio that this sound modual produces into a WAV file all you have to do is record the outputs of the modual into your favourite audio recording package just like you are recording your guitar/mic/drums/tin whistle or what ever you play.
If you have a sound card in your computer or use software synthesis then you will need to record the outputs of the sound card which can create a ground loop that will dump all weird noises into your audio card. There is an easy way to fix this for around $20. Also feedback may occur because of input monitoring.
Wingroove is one program that i know of that can create WAV files from a MIDI file since it has a sound bank of its own which it uses to create the sounds. This method is not very commonly used due to it not being very flexable like an external sound modual.Your stuck with only 128 different sounds to choose from.
How do I improve my midi sounds ?
Visit this link to hear the difference a good quality soundcard can make. If you want higher end sounds you will need to use expensive sound moduals like the roland JV1010 or use virtual instruments like sampletank or gigastudio with a gsif compatable soundcard.
