1x M-Audio Profire lightbridge
4x octopre's
Logic on a mac

Would that give me a full 32 channel recording setup. I don't think logic has any limits on inputs unlike protools M or LE which is 18.

Can anyone suggest anything I'm missing. Or any compatibility issues with Logic or even a better way to do this.


Thanks in advance.

Well, I can comment on part of the setup--I use the Profire Lightbridge but, in my case, have a DM1000 mixer on the front end and record with Audition on a PC at the other.

The Lightbridge "does what it says on the box" and, in my case, worked without a hitch straight away. I've done tests with all 32 channels and it seemed to record without clicks or pops--I stopped checking after 30 minutes. However, in "real life" I have yet to exceed 16 tracks at a time. My home studio is too small and I don't have enough mic stands to do much more!

A few things to consider:

First, the Lightbridge manuals are full of warnings not to hot plug the Firewire connection at the risk of damage to your PC. This doesn't sound like much but it can be a pain to make sure your PC is powered down before connecting the Lightbridge. A quick decision to tidy a cable can suddenly mean a full reboot. At least once, I've forgotten and plugged in while the PC was active with no problems (and forums are full of people who say they do it all the time) but this one has me slightly paranoid.

Second, have a thought to your word clock set up. You'll likely use the Lightbridge as the master and slave the Octopres. Done properly this would mean some kind of active distribution for the worldclock signal though it will PROBABLY work using BNC "T" pieces. I've certainly fed 4 external devices with T pieces but it's a case of user beware.

Third, it seems that audio devices can be fussy about the Firewire chipset used in the computer--the usual advice for PCs is to stick to TI chipsets, either built in or in an external adaptor. Not being a Mac owner, I didn't pay attention to what's what with that system, but know I've seen some reference to problems with some combinations. It's probably worth doing a bit of Googling.

Fourth, you probably know this already but, from memory, the ADAT outputs are an optional extra you'll have to buy for the Octopre devices.

As for the suitability of Logic and whether the Mac will be able to handle 32 simultaneous channels, I'll have to leave this to others!

Bob

That sounds like a good setup.



My current mobile recording rig is kind of the same idea. I have an o2R with an ADAT out card and a M-audio profire 26x26 interface. Mic channels 1-8 are straight into the desk and then out on ADAT using the direct outs to the profire. Channels 9-16 go into the profire then out on ADAT to the o2R. Most of the time I never have to record more than 16 tracks however if I did I would just buy another ADAT out card and have channels 17-24 going into the o2R and then out on ADAT to the profire.



You have not made it clear what is going to go in front of your setup. So for example if you were recording a live band would you double mic everything/use splitters or is this off the direct outs from a desk?



On paper it looks good as IIRC logic has up to 255 tracks so your should be just fine

As Kevin says you should have no problems with track count in Logic. in fact most top end DAWs have almost unlimited track counts!

The limiting factor is the power of the processor in your Laptop/PC

A half decent laptop will allow several dozen tracks without any problems at all BUT - beware of using loads of plug-ins as these eat up the CPU performance faster than anything else!

Try to record with as little as possible in the way of effects and wait for mixdown to add all the 'bells and whistles'

Another thing you might have to consider is the (sometimes depending on system/software) 2Gig file size limit which means you may have to plan the breaks in performance with starting a new project file for part two etc. when you are recording long gigs with a lot of tracks

And finally, the three golden rules of recording to software: Back it up, back it up again and back it up yet again!

Cheers
Anton

Er, processor power is rarely the limiting factor in basic recording. The most common issue is the ability of the disk to write (or read in the case of playback) quickly enough. Processor power tends to come into play during the editing/mixing process when real time effects are in use.



Yes but even without performance being a factor, it's bad procedure to record with effects as this limits your options later on. Far better to record dry and do your effects during the mix.

Cables.

A 32 channel loom will cost you £100 upwards depending on quality (Ebay bargain special vs Van Damme quality expense)

Cheers,

Peter

bob really hit the nail on the head with the hard drive issues. faster drives are a good idea, preferably on a dedicated disk designated for recording. it might even be worth considering solid state drives, if you can afford them! they don't suffer half as badly from fragmentation because they're random accessible. you could then copy your show to a cheaper bank of conventional HDDs to free up your SSDs.

Yep hard drive is where the bottleneck is in almost any system whilst recording. In reaper and samplitude it shows 1% CPU and 30% disk when recording 16 or so tracks. My ageing laptop does still work fine but ever now and again will get a “log jam” and stop recording for a bit. Going on the 30% for 16 tracks (On my desktop which has a SATA drive) you should be fine with 32 tracks.



Those track counts are 24bit at 48 KHz and as you are using ADAT I would imagine that is what you would use, of course higher sample rates need faster hard drives and I have yet to hear a good argument for going to 84 KHz or high sample rates.



Ohh and +1 on the solid state drives, very fast and once you are done recording just bump the tracks onto a “normal” hard drive for mixing.

Cant really comment on your proposed setup but...

I have an M-Audio Firewire 1814 which is a firewire interface quite similar to the profire, regarding the hot plug warning. You can get away with doing it without any hardware damage but in my case my Mac Pro usually kernel panics. This is probably due to a quirky driver more than anything else.

On that note M-Audio have a reputation for having high quality hardware on a budget but unfortunately the same cannot be said regarding there drivers.

It might be worth thinking about Octopre LE's rather than the standard Octopre as the LE (despite its lower price) supposedly has better preamps.

Cheers

James.

I would certainly recommend increasing the quality of the ADAT interface in question.
We have been using multiples of the Presonus Lightpipe and whilst more expensive it has proven to be rock solid (More than my experience with M-AUDIO!) and comes with analogue monitor outputs. If you are looking at spending the amount of money you are I think this would be a worthy substitution!

Dom

Hey thanks for all the infoguys. Really helpful.

Dom - What software have you been using? Any computability issues with logic? I like the look of the presonus nicely rack mountable and not that much more expensive considering I just found out I can get Logic for silly money on a charity price.


As for file size limits. I have a 3.0Ghz mac pro with 8gb of ram and some decent speed hard drives (7200rpm I think) However an ssd isnt out of the question in the long run. A 2gb limit seems a little small, and for recording live shows quite a pain. Can anyone shed any light on this one.

I know the FAT32 filesystem (used on some portable hard drives, memory sticks, ect.) is limited to about 4GB for files, which is a pain as it is the only filesystem you can reliably read and write to from Windows, OS/X and Linux. NTFS (windows) and HFS+ (mac) have a limit of something stupidly huge, but aren't very compatible from the opposite OS.

As for limits on Logic, I have no idea.

Slightly OT, I too have heard reports about the LE version of the Focusrite unit being a better sounding unit than it's more expensive full fat brother. I only have the LE to listen to so can't compare. I guess it may be a technological advancement. A bit like me preferring the sound of the M7CL to the larger, more flexible (for some things) but somewhat older PM5D.

Rob

I'd also suggest changing your file recording format to CAF in Logic. Broadcast Wave and AIFF both have file size limits which I've run into in the past.

Rotation speed tells next to nothing about how fast the hard drive actually is in practice, it's the data transfer rates you need to be looking at. SSD's are great and I'm in no doubt at all they'll replace conventional hard drives in a few years, but for now I'd go with a RAID 3 array of conventional disks if you can. And yes, I did say RAID 3 - you rarely hear about it and it's not used much because it's got crap random access, but for sequential reads and writes it gives you good performance as well as resilience against losing a disk.

As for file size limits, yes FAT32 is the widely used cross compatible file system, but do you need it to be cross compatible? HFS+ gives you 8 odd exabytes in terms of a file limit and is overall a much better filing system (then again these days, what isn't!) Again I'm going to make a strange recommendation here though... if you don't need doze to access the files, give ZFS a try. IMHO probably the best file system around today.

Couple of seemingly strange recommendations there that might well just stay that way - but might be worth a look :-)