A faster connection between Motu 8pre and Mac Pro

[RobertSix]

I have a motu 8pre from the generation when it still had firewire 6 pin connectors. I currently plug it in to the MP with a 6-pin to 9-pin cable. I'm not sure if this is the best method, or if there is a better way to connect.

Recently I upgraded to SSD, and learned that I couldn't get a benefit from 6G drives because my MP is limited to 3G in the HD slots. Then I learned that OWC has this accelsior thing that can go into the PCI and wallah... 6g+ ssd. This to me was a bit mindblowing and made me realise I need to ask more questions and re-examine what I know about my setup and how it can be improved, hence the question about how I'm connecting my audio device to the tower.

I'm trying to reduce the latency as much as possible. Do you know of any hacks to improve this connection? I believe it can handle 400mb/s beacause it is a firewire 400 device on the motu, but might there be a way to improve this somehow?

 

[derbothaus]

Not really. FW400 is fine for most small recording sessions (under 16 streams at once maybe more not sure) Latency is controlled mainly in the driver implementation and the unit you bought. For example I get as low as 2.6ms round trip through my ULN-2 @96KHz 32 samples. Usually I record just straight 44.1KHz and 32 samples with about 4.8ms latency. Pretty good for non PCI based. It uses a FW400 connect and I use a standard cross over FW800-FW400 cable. Your DAW adds even more latency but if you are getting slap back effects you may just need to tweak. Point is FW400 is perfectly suited to audio recording and a bit better than USB 2. It doesn't have the bandwidth of PCI but it gets the job done. Bandwidth and latency are, for the most part, unrelated.

 

[RobertSix]

Not really. FW400 is fine for most small recording sessions (under 16 streams at once maybe more not sure) Latency is controlled mainly in the driver implementation and the unit you bought. For example I get as low as 2.6ms round trip through my ULN-2 @96KHz 32 samples. Usually I record just straight 44.1KHz and 32 samples with about 4.8ms latency. Pretty good for non PCI based. It uses a FW400 connect and I use a standard cross over FW800-FW400 cable. Your DAW adds even more latency but if you are getting slap back effects you may just need to tweak. Point is FW400 is perfectly suited to audio recording and a bit better than USB 2. It doesn't have the bandwidth of PCI but it gets the job done. Bandwidth and latency are, for the most part, unrelated.

I didn't think firewire could handle that much, but I haven't done the math! So thanks for that.

I don't get a noticeable slap back effect, but overall I have about 3-4ms latency and I guess I am aiming for as close to realtime as possible. If I drop down below 100 samples it is fine until the production starts to get a bit heavier then I get all sorts of weird things, causing me to freeze tracks and so on for playback. This, obviously has nothing to do with the firewire connection and probably more to do with... ram? cpu? hdd?

 

[derbothaus]

I didn't think firewire could handle that much, but I haven't done the math! So thanks for that.

I don't get a noticeable slap back effect, but overall I have about 3-4ms latency and I guess I am aiming for as close to realtime as possible. If I drop down below 100 samples it is fine until the production starts to get a bit heavier then I get all sorts of weird things, causing me to freeze tracks and so on for playback. This, obviously has nothing to do with the firewire connection and probably more to do with... ram? cpu? hdd?

Yes, Yes, and Yes

 

[DPUser]

Does that 8Pre have a hardware mixer built in? Unless you are recording VI's or simply must monitor thru effects, you can use a hardware mixer to provide you with near-zero-latency monitoring while recording regardless of buffer size. I keep a hardware reverb patched in at all times for delay or reverb as may be desired while recording, returned only to the monitor mix.

PS: DP8 released today!

 

[spoonie1972]

Edit: Seems DPUser beat me to it


You shouldn't be trying to record with Software Monitoring "on" in the first place - it can really screw up your takes and you can lose the jive, pocket, or whatever other terminology one uses to define timing.

If that box is anything like the 2408 or the 828fw, it has a monitoring engine built into the unit that is as near to zero latency as you can get.

If you insist on monitoring with effects on, may god help your soul... or get a used Protools HD setup (4 *samples* latency). Some of the newer native boxes have post-input/monitoring effects built into the rack. Seems these things are maturing.


YMMV.