Differences In Pro Tools Systems LE vs HD: In the pro tools world there are two main versions of the program and they work in completely different ways. LE: These versions of Pro Tools make use of a usb or firewire audio interface connected to a Mac or PC. The program itself uses the audio interface to pass audio data in and out of the real world and then uses the computers processor to handle the workload of using plugins and managing track counts. Pro tools LE can handle multitrack recording, mixing, editing, Midi editing, the processing of virtual processors (EQs, compressors and the like.) and virtual instruments. It has a maximum resolution of up to 24bit/96khz and a maximum track count of normaly 48 mono or stereo voices at 48khz but they can be upgraded to a maximum 192 tracks with the addition of the various Pro Tools toolkit bundles. In the past, Digidesign/Avid required that the end user only uses their own proprietary audio interfaces for use with Pro Tools. But Since Version 9.0, the Pro Tools suite has expanded to make use of most usb and firewire audio interfaces, regardless if they were made by Digidesign/ Avid. For the purpose of this course we will illustrate just the Digidesign/Avid Interfaces. The Mbox Family The Mbox line of usb audio interfaces are currently in their third generation and there have been some changes, but by and large the current generation and the previous generation are still very similar. The Mbox Mini. They start small with the 2 in 2 out Mbox mini which features 2 instrument inputs and a single microphone preamp with phantom power. This interface operates using the usb 2 protocol and gives Pro Tools users a maximum resolution of 24bit/48khz. The Mbox. The standard Mbox has more features than the mini starting with the addition of a second mic preamp, an inbuilt midi interface, spdif ins and outs and an increased resolution of 24bit/96khz. Like the mini it is also a usb Interface. The Mbox Pro: The pro adds two more mic preamps to the mix for a total of 4. It has 4 additional line inputs 2 auxiliary RCA aux inputs (With a phono compatible RIAA filter.), 6 analog outputs, 2 headphone outs and a breakout cable for midi and spdif ins and outs. While this is a lot of I/O upgrades, perhaps the main improvement is the inclusion of 2 firewire 400 ports on the back which makes communication with Pro Tools much faster. It also has inbuilt dsp for monitoring and reverb. The 003 Family: The only difference between the Mbox line and the 00 line is the amount of I/O included and the fact that you can put a 003 in a standard 19in rack. The 003 and the 003+ The 003 series interfaces are similar to the Mbox pro in the fact that it uses a Firewire 400 cable as a means of communicating with Pro Tools. The main differences are the addition of mic preamps (4 on the 003 and 8 on the 003+), and the amount of analog inputs increases to 8. The amount of analog outputs increases to 8 as well but with the extra addition of 2 main monitor outputs that you can use to switch between two sets of speakers using a front panel switch. The digital I/O remains largely the same with the Mbox line but with the one exception of the ADAT lightpipe (or TOSlink) digital input and output that allows the simultaneous transfer of 8 digital ins and outs over a single cable. This is useful for using additional mic preamps with digital I/O or an analog mixing console with the use of an analog to digital converter or AD/DA converter. You can also use these various interchanges of I/O to supplement the use of outboard effects such as analog EQs and compressors through the use of external AD/DA converters and the lightpipe interface. HD: On the software side of things, Pro Tools HD looks very similar to its LE cousin as far as how the program operates (albeit with some slight modifications). In fact, the transition from using a Pro Tools LE system to using an HD system can be a very seamless process. The difference however is how HD processes and manages the audio stream and processor tasks, such as plug ins and track counts. On a LE system it is the job of the main processor of the host computer to do most of the heavy lifting in a Pro Tools session. It is quite possible to overload your main CPU just by having to many tracks open at once, or by having too many plugins running in a single session. By using an HD system however, the task of the host CPU is almost eliminated entirely (with the exception of mundane things such as, drawing the Pro Tools GUI on the computer screen). It works by using PCI-e cards called Core Cards and Accel cards to take the burden of processor intensive tasks away from the main CPU. It accomplishes this feat by using 9 DSP prossessor chips per card to act as surrogate CPUs designed to calculate large amounts of linear data such as real time audio. Each card can handle 32 tracks of I/O and up to 96 audio voices at once and a single HD system can accommodate 1 Core card and 2 Accel cards for a total of 96 tracks of I/O and 128 audio voices. HD I/O: Another way a Pro Tools HD system operates differently to its LE cousin is the fact that when you buy an all in one interface like an Mbox or a 003, all of the hardware that you might need is included in the box. It’s almost like most of the important components of any digital studio are built together in one convenient package. A 003 interface contains an inbuilt, A/D D/A converter, microphone preamps, a master summing buss, and direct instrument and line level I/O; THAT’S A LOT OF STUFF! But when you buy a pro tools HD system it is designed to be completely modular. That means when you buy the Core and Accel cards with the necessary software included; it is still not enough to start recording. You would still need to buy some A/D D/A converters, mic pres, direct and instrument inputs and perhaps a monitor/master summing device. This approach also makes using large format analog recording consoles, such as, the SSL 4000G+ a much more concise and practical task. M-Powered: There is yet a third version of Pro tools Available. M-powered is an attempt to give everyone from every budget a chance to use this powerful recording system. M-Powered is essentially the Pro Tools LE software suite designed to be purchased as a standalone software package and married exclusively to an M-Audio branded audio interface (sold separately). The software is near identical to its LE cousin in every regard except for the fact that the track counts are limited to 48 voices and it is not possible to mix in surround in the M-Powered version. There are possibly thousands of ways to approach building a Pro Tools system. We will cover many of these possibilities in our in-class discussion. Please keep this guide handy for future reference and also if you yourself need some help choosing the right system for you. Thanks for reading. Mr. Wigley (The Wizard)..