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bexbissell

macrumors newbie
Original poster
Nov 15, 2008
2
0
Hi all,

I was recording a session over the weekend on my iMac 24" (2.4ghz/4GB ram) using Logic Pro when I started to experience intermittent high volume audio crackling/interference whilst recording audio tracks.

I believe this may have been caused by my Audio card (Focusrite saffire pro 10 I/O) sharing the same Firewire bus as my external hardrives (2 drives in a Galaxy Metal Gear RAID enclosure) as the noise ceased when I moved the drives onto the USB port.

(I tried connecting the Harddrive via FW400 and also daisychaining it to the Sound card but the noise returned.)

Here is how I had my system set up:

iMac - FW400 port > Focusrite Sound Card
iMac - FW800 port > Galaxy Metal Gear Hard drive - Disk 1 - Audio samples (BFD - 250GB) / Disk 2 - Audio recording drive (250GB)


Now I am unsure how to continue.

If I connect the Hard drive caddy via USB I am concerned that it won't have enough bandwidth to stream audio samples whilst recording audio.

Also, as I have a 500GB Time Capsule connected to my iMac via Ethernet. I was wondering if Ethernet is usable for Audio work, either as a recording drive or as a sample holding drive?

as I was considering this setup:

iMac - FW400 port > Focusrite Saffire
iMac - USB2 port > Galaxy MG Hardrive - Disk 2 - Audio recording drive (250GB) / Disk 1 - unused/backup
iMac - Ethernet port > Time capsule - Audio samples (BFD - 500GB)

is this madness?

Perhaps another option would be to get another caddy for the unused drive and connect like this:

iMac - FW400 port > Focusrite Saffire
iMac - Bus 1 USB2 port > Galaxy MG Hardrive - Disk 2 - Audio recording drive (250GB)
iMac - Bus 2 USB2 port > New hardrive enclosure - Disk 1 - Audio Samples

Can anybody offer any suggestions as to what would be the safest, fastest or most reliable setup, I'd really like to be able to take advantage of the FW800 speed if possible?

:confused:

Thanks everyone.

links:
http://www.galaxymetalgear.com/products/3500_mgbr.html
 

product26

Cancelled
May 30, 2005
777
9
I have experienced problems when sharing the firewire bus with both my interface and a hard drive. Even tho you have a separate 400 & 800 ports, they share the same bus. This limits your set up quite a bit. USB simply wont keep up... at all.

With an iMac, your best bet is to use the internal SATA drive for working files & the external for storage.

To test this, transfer the session/files to the internal hard drive and try again.
 

Fishrrman

macrumors Penryn
Feb 20, 2009
28,246
12,388
RE:
"I believe this may have been caused by my Audio card (Focusrite saffire pro 10 I/O) sharing the same Firewire bus as my external hardrives (2 drives in a Galaxy Metal Gear RAID enclosure) as the noise ceased when I moved the drives onto the USB port."

I would say that, if you tried the above configuration and "the noise ceased", then stick with it.

One other thought. You have 2 firewire ports, one 800 and one 400, is that correct?

If so, I'd suggest connecting the Saffire to the 800 port (use a 9-pin to 6-pin cable), and connect your hard drives to the 400 port. You might consider connecting only ONE of the external hard drives, the one you're actually recording audio files onto.

Another approach is the one that I use myself. I have a white Intel iMac and have the internal drive partitioned, with several smaller-sized (8 gig or so) partitions set up for my audio projects. The small partition size limits the physical area that the drive must "write to" and keeps my audio files separated from all other files on the drive. I find that I can record 2 24-bit tracks without any problems at all. Haven't tried using more than 2 tracks simultaneously yet. But the iMac processor and internal drive handles this easily. You don't have to record to an external.

- John
 

johnboner

macrumors newbie
Oct 7, 2009
2
0
Focusrite&firewire hd

Hi!

I have the exact same problem with my setup, 2,66iMac,Saffire pro 26 and a WD 500gb external hd,both firewire. Has anyone solved this problem? Maybe a firewire hub could do the trick, then I could use just one fw-port on my mac.
 

schlep

macrumors newbie
Dec 6, 2010
1
0
same problem with firewire bus.

I suppose it's a bandwidth issue. Silly that the 800 and 400 firewire ports share the same bus. What's the point in having two ports if you can't use them both.

I have a firewire800 external drive and a firewire400 audio card. I only use the drive for backups so I just leave it unplugged most of the time but I feel like i should be able to keep it plugged in. When I do have it plugged it it will crash my audio card altogether if I open any audio software. I mostly just use Traktor for DJing and the sound card will crash if I open Traktor with my harddrive plugged in. Super lame.

I suppose we should report the problem to Apple and perhaps they will remedy it in future models as I don't see an option to make them work together currently. I suppose I could use the USB connection and leave my harddrive plugged in as I don't really need the speed of the FireWire800. I bought the firewire 800 model because I had that extra port on my computer so I thought "Hey, that's an awesome place for a backup drive." apparently not if you have a firewire audio interface.
 

Starrla1000

macrumors newbie
Dec 11, 2010
1
0
Malibu, CA
I have read on the net that most audio engineers are going with an eSATA card for their external hard drive connection via your expresscard/34 slot. The expresscard/ 34 slot is a separate bus from your dual/connected firewire 400 & 800 bus. Having your external hard drive on one bus and your audio interface/ card on the firewire ports does best. Chose an expresscard/34 adapter and external hard drive with a connection like eSATA for the streaming speed.
 

johnboner

macrumors newbie
Oct 7, 2009
2
0
Problem solved...maybe

Last night I decided to try my fw-hd with my fw-saffire-interface. Same damn crackling/hissing wouldn't go away. Someone told me I should check my Audio Midi Setup on my mac. I changed the clock source to "mac".

Everything runs just right now! At the same time I'm pissed off and happy!
 
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