DIGITAL RECORDING BASICS

DIGITAL RECORDING BASICS

MUM 2600

Professor Calle

Miami-Dade College SEDT

MUM 2600

Professor Calle

Miami-Dade College SEDT

Sample RateSample Rate

Sample Rate: The amount of times sound wave information is sampled or recorded per second during the digital recording process.

Sample rate is measured in kilohertz (kHz). Higher sampling rates improve the sampling

frequency range and thusly create more accurate recordings.

Sample Rate: The amount of times sound wave information is sampled or recorded per second during the digital recording process.

Sample rate is measured in kilohertz (kHz). Higher sampling rates improve the sampling

frequency range and thusly create more accurate recordings.

Sample Rate - continuedSample Rate - continued

The standard sample rate for all commercial CDs is 44.1kHz.

The default sample rate students will use for MUM 2600 is 48kHz.

The Nyquist Theorem states that in order to capture digital sound accurately, one must sample at twice the highest frequency.

Since humans hearing range is 20Hz to 20kHz, the standard has become 44.1kHz.

The standard sample rate for all commercial CDs is 44.1kHz.

The default sample rate students will use for MUM 2600 is 48kHz.

The Nyquist Theorem states that in order to capture digital sound accurately, one must sample at twice the highest frequency.

Since humans hearing range is 20Hz to 20kHz, the standard has become 44.1kHz.

Sample Rate - continuedSample Rate - continued

Sample rates vary for different software and hardware DAWs*. Consult your manuals.

Sample rates for Digidesign hardware:– M-Box = 44.1 and 48kHz– 002 = 44.1, 48 and 96kHz– HD = 44.1, 48, 96 and 192kHz

*DAW = digital audio workstation

Sample rates vary for different software and hardware DAWs*. Consult your manuals.

Sample rates for Digidesign hardware:– M-Box = 44.1 and 48kHz– 002 = 44.1, 48 and 96kHz– HD = 44.1, 48, 96 and 192kHz

*DAW = digital audio workstation

Bit DepthBit Depth

Bit depth refers to the number of bits used to describe each sample generated during the recording process.

If one records at a 48kHz sample rate and a 24-bit depth this means there are 48,000 individual 24-bit representations of sound recorded every second.

The standard bit depth used on commercial CDs is 16-bit.

Bit depth refers to the number of bits used to describe each sample generated during the recording process.

If one records at a 48kHz sample rate and a 24-bit depth this means there are 48,000 individual 24-bit representations of sound recorded every second.

The standard bit depth used on commercial CDs is 16-bit.

Bit Depth - continuedBit Depth - continued

Higher sample rates and bit depths require larger hard drive space.

Note: 24-bit recordings require 50% more hard drive space than 16-bit recordings.

The default bit depth for MUM 2600 is always 24-bit.

Higher sample rates and bit depths require larger hard drive space.

Note: 24-bit recordings require 50% more hard drive space than 16-bit recordings.

The default bit depth for MUM 2600 is always 24-bit.

Hard DrivesHard Drives

For best results always use:– ATA/IDE, SCSI or Firewire drives operating at

7200 rpm drive spin speed. – Firewire drives must contain the Oxford 911 or

921 chip.– Drives must have a 3-Megabyte transfer rate

and a 10-millisecond seek time. You may not record directly to a CD or DVD

because they are too slow for digital audio.

For best results always use:– ATA/IDE, SCSI or Firewire drives operating at

7200 rpm drive spin speed. – Firewire drives must contain the Oxford 911 or

921 chip.– Drives must have a 3-Megabyte transfer rate

and a 10-millisecond seek time. You may not record directly to a CD or DVD

because they are too slow for digital audio.

Hard Drive RulesHard Drive Rules

Do not record onto your main system drive.– Digital recording causes heavy disk fragmentation and

can and usually will cause your directory data to be so fragmented that the hard drive will stop working and you will loose all of your data.

Backup your work to a secondary drive, CD or DVD.

Defragment your drives regularly using software such as TechTool Pro or Norton Utilities.

Do not record onto your main system drive.– Digital recording causes heavy disk fragmentation and

can and usually will cause your directory data to be so fragmented that the hard drive will stop working and you will loose all of your data.

Backup your work to a secondary drive, CD or DVD.

Defragment your drives regularly using software such as TechTool Pro or Norton Utilities.

More Hard Drive RulesMore Hard Drive Rules

Always un-mount a drive prior to disconnecting it from your computer.

You may un-mount a drive using a disk utility or by simply dragging it to the trash. After that, wait until the lights stop blinking or the drive is no longer visible on the desktop.

This is specially critical with removable SCSI and Firewire drives.

Always un-mount a drive prior to disconnecting it from your computer.

You may un-mount a drive using a disk utility or by simply dragging it to the trash. After that, wait until the lights stop blinking or the drive is no longer visible on the desktop.

This is specially critical with removable SCSI and Firewire drives.

Class Hard Drive ProceduresClass Hard Drive Procedures

Create a folder called, LastNameFirstInitial- Calle2600, on one of the Firewire drives of the Macs in the Pro Tools lab and MIDI lab respectively. Create this folder in both rooms.

The folder name should look like: CalleE-Calle2600.

All of your projects will go in these folders and these folders only. You may back up your work to your own drives if you like.

Create a folder called, LastNameFirstInitial- Calle2600, on one of the Firewire drives of the Macs in the Pro Tools lab and MIDI lab respectively. Create this folder in both rooms.

The folder name should look like: CalleE-Calle2600.

All of your projects will go in these folders and these folders only. You may back up your work to your own drives if you like.

Class ProjectsClass Projects

Projects will be assigned by the professor. Students must complete their own work. No

“qualified engineers” may assist you with your projects or you will fail.

All projects will be turned in on the day specified in audio form.

Absolutely no vulgar language will be accepted for any project. Use a blue word and your project earns an F. No exceptions for any reason under any circumstance.

Projects will be assigned by the professor. Students must complete their own work. No

“qualified engineers” may assist you with your projects or you will fail.

All projects will be turned in on the day specified in audio form.

Absolutely no vulgar language will be accepted for any project. Use a blue word and your project earns an F. No exceptions for any reason under any circumstance.

Session defaultsSession defaults

All of your MUM 2600 Pro Tools sessions will use the following defaults:– 24 bit depth– 48kHz sample rate– .wav file audio file format

All of your MUM 2600 Pro Tools sessions will use the following defaults:– 24 bit depth– 48kHz sample rate– .wav file audio file format