RECORD/PLAYBACK OF 8 CHANNELS AT 24 BITS IN
LOGIC AUDIO PLATINUM 4.6.1 USING STUDI/O AND EASI
This application note describes how we recorded 8 channels in Logic Audio Platinum 4.6.1, synchronized to an ADAT XT using the EASI STUDI/O driver in Logic 4.6.1. These settings also apply for configurations greater than 8 channels, but if you want to maintain 24 bit resolution, you'll probably need a faster CPU (and more memory won't hurt either).
|
Hardware |
Software |
|---|---|
| - Pentium-II 300MHz - SUPERMICRO P6SBS motherboard - Matrox G200 AGP Powerdesk graphics card - 128MB RAM - Adaptec AHA-2940U/AHA-2940UW PCI SCSI controller - 2.05GB Micropolis 4221W SCSI hard drive (system) - 4.5GB Seagate Cheetah 4LP SCSI hard drive (audio) - STUDI/O - ADAT XT20 |
- Windows 98 SE - Logic Audio Platinum 4.6.1 - Sonorus 1.996 drivers - Virtual Memory: 256MB minimum, 256MB maximum - Graphics Acceleration: Maximum Matrox settings: PCI bus mastering ON, Device bitmaps caching ON, Filtering when scaling ON, Polygon acceleration ON |
With this setup we were able to easily record 8 channels from the ADAT into the computer. We used the ADAT as the Master Word Clock. The ADAT was set to internal clock at the project sample rate, and STUDI/O was set to lock to Input A. STUDI/O Input A and Output A were connected to the ADAT digital output and input respectively. Note that we are recording 24 bits through STUDI/O to Logic Audio, but the XT20 is limited to 20 bit resolution recording and playback. You can substitute a higher resolution device without changing any of the settings shown here.
First, we see a couple of options by pulling down the AUDIO menu:
If you want to monitor your inputs through Logic, check 'Auto Input Monitoring'. Note that Logic currently doesn't use the zero-latency monitoring on STUDI/O, so for live punch-ins, you should monitor through your mixing board.
This is also a convenient place to set your song's sample rate.
Next, we set up the 'Audio Hardware & Drivers' Preferences:
We have STUDI/O set up using the EASI driver.
Enabling the 20/24 Bit option, you are set to record at 20/24 Bits!
To set the Buffer Size, you will need to go into the Control Panel. There, the largest Buffer Size is 220, which gives the best recording performance and plug-in performance. You might want to use a lower buffer size to reduce latency when doing live punch-ins. Be aware that this will increase the demands on your CPU and disk, however.
Notice that we have selected the EASI driver, and checked off all of the channels for use with EASI. We have the latency set at 100 blocks.
We're not doing mixdowns here, so we don't have a need to go from the normal 8 busses up to 16, but you can get 16 busses by checking the box. Also, you can up the total number of Audio tracks here, which is dependant only on the total system RAM you have. The memory Requirements shows how much you'll need for your new settings.
The other settings shown are recommended by Emagic, and seem to work the best.
Here, you see we have Logic Create waveform Overview after Recording. Just our personal preference...
Next we open the Audio Window in order to set our recording destination:
Here we set up the record Path to point to our super-fast audio disk.
No Logic application note would be complete without at least a reference to the Environment. This powerful concept is beyond the scope of this application note, but at least we can show you the basic audio Environment set up (but we urge you to become adept with the Environment, it's the whole key to Logic):
For recording, we set all the tracks to output from just one stereo pair, to conserve CPU cycles and get the most recorded tracks. Afterwards, you can modify the mixer, taking advantage of the busses and routing available in Logic, and taking full advantage of the outputs available on STUDI/O (16 digital plus 2 analog per card). As with any computer system, playback is way more efficient than recording, so once you have recorded everything into the computer, you can get way more than 16 tracks and 16 outputs.
For more info and ideas about Logic Audio Platinum 4.6 check out these sites:
|
|
|
|
|
Need to upgrade to Logic 4.6.1? Here is the link!
|
Keep in mind, that these are the settings that we used to get this setup working. Your mileage may vary.
