Cary B. Cornett
11-15-2015, 06:30 AM
Today I will be recording a choir concert. The last time I recorded this choir was the first field recording I had done since upgrading my interface to a MOTU 2408 MKIII (from a MKII). At the same time, I had set up a new old computer for field work so I didn't have to pull out my studio DAW. This machine got the 424 PCI card that came with the MKIII I bought.
My purpose in this upgrade was to be able to go up to 96k sample rate if I want. In the portable rack (used in studio and for remotes) with the 2408 MKIII I have two PreSonus Digimax FS (serious improvement over the ADA8000 units they replaced). These worked very well with the old interface.
In the old setup I used one Digimax unit with the ADAT A ports on the 2408, and the other with the ADAT B ports. I always clocked the Digimax from the 2408 via ADAT.
Now, the Digimax has two sets of ADAT optical ports. At sample rates up to 48k, the first set handles all 8 channels. Above that rate, each set carries only 4 channels. I wanted to be able to go to the high sample rates without moving any optical cables. So,
ADAT A of the 2408 now goes to the first port on the first Digimax,
ADAT B of the 2408 goes to the first port on the SECOND Digimax, and
ADAT C of the 2408 goes to the second port on the FIRST Digimax.
I have not yet tried to run anything at 2fs, but when I first tried to record with the new setup, I got random clicks that indicated a clocking problem. I didn't have time for extensive troubleshooting, so I tried setting the first Digimax unit to internal clock (I only needed 7 inputs for this session). After that, everything was rock solid.
So, I'm left to wonder what caused the clocking problem. Was it the new 424 card, the Audiowire cable, or some defect in the 2408 mkIII? One other possibility is that the Digimax unit doesn't like being split between ports A and C for high sample rates, even when the LOW sample rates are being used.
Today I will be using a different Firewire cable that I tested in the studio with the old mkII unit.
Has anyone else here run into a similar problem with similar equipment? If so, what solution did you find?
My purpose in this upgrade was to be able to go up to 96k sample rate if I want. In the portable rack (used in studio and for remotes) with the 2408 MKIII I have two PreSonus Digimax FS (serious improvement over the ADA8000 units they replaced). These worked very well with the old interface.
In the old setup I used one Digimax unit with the ADAT A ports on the 2408, and the other with the ADAT B ports. I always clocked the Digimax from the 2408 via ADAT.
Now, the Digimax has two sets of ADAT optical ports. At sample rates up to 48k, the first set handles all 8 channels. Above that rate, each set carries only 4 channels. I wanted to be able to go to the high sample rates without moving any optical cables. So,
ADAT A of the 2408 now goes to the first port on the first Digimax,
ADAT B of the 2408 goes to the first port on the SECOND Digimax, and
ADAT C of the 2408 goes to the second port on the FIRST Digimax.
I have not yet tried to run anything at 2fs, but when I first tried to record with the new setup, I got random clicks that indicated a clocking problem. I didn't have time for extensive troubleshooting, so I tried setting the first Digimax unit to internal clock (I only needed 7 inputs for this session). After that, everything was rock solid.
So, I'm left to wonder what caused the clocking problem. Was it the new 424 card, the Audiowire cable, or some defect in the 2408 mkIII? One other possibility is that the Digimax unit doesn't like being split between ports A and C for high sample rates, even when the LOW sample rates are being used.
Today I will be using a different Firewire cable that I tested in the studio with the old mkII unit.
Has anyone else here run into a similar problem with similar equipment? If so, what solution did you find?