we'll need more information to make a judgement. What's your Mother board, cpu, ram, and all hard drives. You should have 1 hard drive for OS and programs, one for audio recording and one for samples.

My only suggestion would be to add a FW800 hub.

I doubt that your firewire is to busy, it's the nature of daisy-chaining that the first device in the chain has to pass all of the data, all devices are not created equal, some take more time, a hub will make the data available to all devices at the same time.

2,8GHz Intel Core i7, internal drive (for system only) is 500GB 7200rpm

How does one add a FW800 hub to a MBP without the express port? I remember looking for that product a while back, but not finding anything.

I made the decision to have just one drive for both projects and samples, 1. because I didn't think adding a second drive would increase performance if I was gonna daisy chain anyway, and 2. because of portability convenience. But maybe I was wrong in those assumptions..
I'm wondering if a USB drive would be fast enough to ease some load off the Lacie drive, for either projects or samples. Bus-powered USBs seems to come no faster than 5400RPMs, but maybe the rpm speed isn't a bottle neck (I heard that mentioned in some places)

Another option would be to get the FF-UFX, and run it on the USB port (assuming the daisy chaining is the issue). If running both projects and samples off the same disk is the problem I'm not sure what would solve it..

Thanks again, I'm grateful for further advice!

Using the same drive for audio files and samples can cause the drive read head to constantly skip between different physical locations of the drive, so it ends up spending more time seeking than actually reading, and you don't achieve the full potential speed. The firewire bus isn't the bottleneck in this case.

The OP states he is using a La Cie drive for the audio so that eliminates the OS/Audio drive issue. Actually IMHO the La Cie drives are not up to snuff especially if transferring via 1394B. The Apogee One doesn't exhibit the same issues because the channel count is insignificant. The more or less standard external hard drives are made by Glyph.

This shouldn't be the problem for that MBP but in older motherboards the ICH memory controller was traditionally the fault point for daisy chaining 1394 devices in 1394B protocol.

Rasmus Faber, post: 377129 wrote: 2,8GHz Intel Core i7, internal drive (for system only) is 500GB 7200rpm

How does one add a FW800 hub to a MBP without the express port? I remember looking for that product a while back, but not finding anything.

I made the decision to have just one drive for both projects and samples, 1. because I didn't think adding a second drive would increase performance if I was gonna daisy chain anyway, and 2. because of portability convenience. But maybe I was wrong in those assumptions..
I'm wondering if a USB drive would be fast enough to ease some load off the Lacie drive, for either projects or samples. Bus-powered USBs seems to come no faster than 5400RPMs, but maybe the rpm speed isn't a bottle neck (I heard that mentioned in some places)

Another option would be to get the FF-UFX, and run it on the USB port (assuming the daisy chaining is the issue). If running both projects and samples off the same disk is the problem I'm not sure what would solve it..

Thanks again, I'm grateful for further advice!

You would connect the hub via the existing firewire port, all data is present at the ports at the same time, and available to each device.

Daisy chaining a second drive won't be a problem at moderate track counts at all. If you had money for a UFX that would indeed eliminate the chaining issue. USB drives do indeed come with 7200rpm hdd. Mostly in pro level enclosures. Glyph drives again are the standard but I frequently have made my own using enclosures with Oxford 924 or 934 chipsets and Seagate bare drives.