First of all. I want to rave on about d24 Pro Tools. I have been using various systems since September ‘97 with excellent results. Recently I went into the studio to cut tracks on a Sony 3348 48 track digital machine. In the past when multiple takes had to be edited together we would rent a second 48 track machine and copy the pieces from one machine to the other much like video editing. The Sony machines lock to one millisecond accuracy, and perform all required edits flawlessly.

Sometimes the edit points don’t work with all 48 tracks edited in exactly the same place. If a guitar pickup is earlier on one take or a bass note rings over the edit point on another take, the edit points will be different for each track. With a tape based machine you have to perform multiple passes over the required edit spot changing the edit point slightly each time to accommodate the variances. This is where hard disk editing comes in.

This time instead of two Sony 48 track machines, we decided to use one Sony 48 track and a d24 Pro Tools system. Since the edits would be done on the basic tracks before the overdubs, there would only be 24 to 32 tracks to deal with during the editing. The interface to the Sony 48 track would have to be digital, and we would have to have lots of storage that was readily available when we needed to change tunes.

The digital transfer was easy. An Otari UFC-24 format converter box was used to get the digital data back and forth between the Sony 48 track and Pro Tools. One UFC-24 will convert 24 channels of digital audio from any format to any other format. Previously I have transferred 48 channels at a time by using two UFC-24s synced together. They work flawlessly. Digital audio signals can also be rerouted as they pass through the UFC-24. If you want track 17 of the source machine to end up on track 3 of the destination machine you are only a button press away. You can reroute all 24 channels at once if you want to.

Two New Gig Toys

In my system I do a lot of transfers between Pro Tools and ADATs. I have also found that I never have enough physical channels to get in and out of my Pro Tools system. Until this week, I had two 888/24 I/O interfaces and one 882 I/O interface. This gave me 8 digital or analog ins and outs from each 888 box, and 2 digital or 8 analog from the 882 box. I needed more digital I/O. Digidesign just started shipping their new ADAT Bridge, one of which went right into my Pro Tools system.

Unlike Digidesign’s previous ADAT Interface, the second generation ADAT Bridge is a snap to install and works without a hitch on the first try. The box occupies a single rack space and acts like two eight channel interfaces, giving you 16 channels of digital I/O on ADAT optical cables. You also get two 20 bit D/A converters for monitoring purposes, and channels 1 & 2 can be AES or SPDIF. AS an added feature, the ADAT Bridge will work in stand-alone mode allowing you to transfer two channels of digital audio from AES (or SPDIF) to or from ADAT optical.

If your primary recording device will be ADATs, you can set up a Pro Tools system so that the only interface is the ADAT Bridge. With the bridge connected to one or two ADAT machines, the ADATs become your analog I/O. In my system now I have two 888 boxes and the ADAT Bridge which gives me 32 channels of I/O. The two 888 boxes are connected with a “Y” cable to the d24 card, the first 8 channels of the ADAT Bridge are connected to a DSP Farm card, and the second 8 channels of the ADAT Bridge are connected to a second DSP Farm card. So far everything works fine, now, where do I store all of this stuff?

I Hate Everything

One of the things that I hate most of all is backing up data. Another thing I hate is running out of room on my hard disk when I only need another 30 seconds of recording time. Since the new d24 Pro Tools system expects to see its storage devices on the Mac SCSI bus, it makes it much easier to experiment with different storage devices.

I get Pro Tools files sent to me on 1 gig Jazz drives. I used to transfer them to a non removable hard disk before mixing. I added a SCSI accelerator card to my Mac 9600/300 and moved the Jazz drives over to the accelerator. I found that I could get 24 tracks of material directly off of the Jazz drive, even if there was a fair amount of editing in the Pro Tools session. I then tried recording directly to the Jazz drive and found that I could reliably record 16 tracks at 16 bits or 12 tracks of 24 bits without overrunning the drive. The only problem was that I could use more than 1 gigabyte. Enter 2 gig Jazz drives.

For the current project I am transferring a lot of data into Pro Tools. Partly because we can listen to previous takes of a song without waiting to change tapes on the Sony 48 track machine. Removable media seemed to be the answer, so I hooked up two 2 gig Jazz drives. I set the disk allocation table so that 12 tracks are stored on each drive, so I basically have 4 gigs of space before I have to change disks. With the DAE buffer set high enough, and the drives connected to the SCSI accelerator card, I have no problem recording 24 tracks at once to the drive pair. When I get to the point where there is not enough room for another take, I just pop in two more Jazz cartridges and go.

For more demanding recording loads, I record to a 9 gig 10,000 rpm Seagate Ultra-Wide SCSI drive. This allows me to record 32 tracks of 24 bit simultaneously onto one drive. With a dual channel SCSI accelerator card and two of these drives and the Digidesign 32 channel upgrade, there is no problem recording and playing 64 tracks at a time.

Session Documents

I found that the longest delay in changing media is opening a new session document and getting everything set to record, so I cheated. After initially setting up the session document on one of the removable cartridges with all of the routing, track names, number of tracks, destinations, etc., I copy the document to the resident hard disk. When it comes time to load new blank cartridges I copy the session document from the internal drive and open it. All I have to do is record enable the tracks and go. Each pair of Jazz cartridges I insert have the same name. The top drive cart is labeled “AA” and the bottom drive cart is labeled “BB”. This keeps me from having to change the disk allocation table each time I reopen the session document on a new pair of carts. The physical labels on the cart show the name of the song stored.

The End

I didn’t mean for this to end up being a Pro Tools column, but I find that I am doing more and more of this kind of stuff to get albums done. Lots of ADAT and Pro Tools sessions including Take 6, Tower of Power, Robben Ford, Less McCann, Shirley Horn, Flora Purim, Bela Fleck, Steely Dan, and others. It seems like bringing your Pro Tools system to a project is becoming as natural as bringing your own near field monitors.