Very simple. I have a concert coming up and I need to record 16 tracks of 24bit 96kHz audio, length about 2 hours. I have 2 MOTU 8Pre firewire interfaces and an Intel 2Ghz MacBook with Logic pro 7 running on it.

Initial trials have not been very successful. I have no problem running 5 tracks at 24/96, but any more and sometime the system will work and other times it falls over ("disk to slow") errors etc. Advice I’ve been given is that the MacBook (2GHz, 2Gb RAM) should be plenty fast enough for this. Basic optimization i've done have improved things a little but not enough to instill confidence that the system will hold up on the night.

I have not had a lot of experience with computer-based recording systems, but they must be more reliable than this! The computer is not running any applications whilst Logic is operational and I have recently performed a clean install also.

There is so much information and I am searching around. However, any advice would be much appreciated. I imagine this must a common problem?

Thanks, Alex.

16 tracks at 24/96 is not an insignificant demand on performance. I'd imagine your hard drive is the weak link in the chain. 2.5" laptop drives are typically slower than larger desktop drives. See if you can experiment with a fast external Firewire drive.

--------------------
Original artwork and unique devices inspired by vintage technology http://www.thisisobsolete.com

why 96kHz - I think you (or someone else) is fooling themselves if they think they need to work at this sampling rate. 24/44.1 is more than fine.

JP

--------------------
Mac Pro, Logic Pro, lots of software and 17 hard drives!

JJ's advice is sound.

If you need that kind of setup: Hire it. I wouldn't trust any laptop for such a project at that sample rate. I don't think your client would either if they knew.

Precarious to say the least! And make sure any recording is thoroughly backed up on site during recording. There's just too much at stake with a gig that size. Hire a mixing desk and a Nagra or somesuch.

ken

--------------------
I'm All Ears.

Also, a recording that size can not safely be in the WAV/AIFF format as you will surpass the file size limit. CAF apparently is what you need for Logic but I haven't seen that option on 7. I hope desmond will be around to clarify. If you have an Intel mac, you could run Bootcamp Windows, and run a copy of Wavelab, which will support RF64 recording. CAF on OSX or RF64 on Windows: your file size limit will be dictated by your available disk space.

HTH

ken

--------------------
I'm All Ears.

I agree, you don't need 96khz, 44 or 48 at 24bit will be just fine.
Plus, if you update your internal drive to something like a Western Digital Scorpio Black ( running at 7,500 instead of 5,400 rpm ) it will take the strain off the drive and doesn't cost any more than filling up your car .
Run an External Firewire drive to do a simultaneous back up too !
Good Luck.

I just did a similar thing, recorded a live concert using Logic 8 on a 3 year old MacBookPro (3GB, 2.33GHz), a Focusrite Pro40 interface and a Behringer ADA8000, onto a 5200 rpm USB2 harddrive.

I was recording in 24/44.1 and in a live setting like this I can't believe You could hear any differences in using 96Khz instead.

I must stress that using 24bit is a lifesaver though, it let me have a big safety magin on the preamps so not to overload the A/D's!

I worked perfectly!

I had tried this in rehearsals before to be safe that the tech would work and I ran into a strange issue were Logic apparently ran out of memory after a couple of hours (at that time I was stopping and starting the recording after each song, not really true to a real live recording).

I then remembered someone mentioning that the undo history in logic can use up a lot of memory, so I adjusted the number of undo steps down from Logics default of 30 to 5 and I have not run into that problem again.

Another thing You might do when recording long live sessions is, make sure You use CAF as audio file format instead of Wav or Aiff.
Wav and Aiff are limited to 2GB filesizes, CAF are basically unlimited.
If something would happend, the machine would crash for instance, Wav and Aiff file can get corrupted and even if You have recorded an hour of material they can't be opened. CAF is designed to be able to be used even if it wasn't closed properly.

I see 3 potential issues with Your setup:
Memory: Logic loves more than 2 GB, otherwise it will start to swap in and out from the systemdisk.
Disk: Don't record to the internal disk, it is shared with the OS and it's swapping mechanism have highest access priority to the disk.
Mhz: 96 is overkill especially in a live context IMHO... And it will put a big strain on all components in Your setup.

Good luck!
Janne

How many simultaneous tracks did you record.

I have a Macbook Pro (first edition) and it really struggles on multiple tracks.

--------------------
The only excuse we have for making music in the first place is to make it differently..vis-a-vis our own difference (Glenn Gould)

I've done some basic tests with Cubase on a macbook with the Profire lightbridge and managed 32 tracks at 24 bit 44.1K with no problems.

Lizardpoint

Hi
Recording performance is dependent on speed, processor, fsb and hard drive access speed - everything has to be optimised.
AV software needs to be disabled, also internet access, wifi and any other background services that can affect the recording process.
Do not forget that the interface capability is very important, firewire 400 is only just good enough 96K, remember you have to divide down interface speed by the channels you are using, so with a firewire 400 and 10 channels you have handshakes of a mere 40MHz, 16 channels almost halves this again.
For the best, use a dedicated hard drive or machine for music only, setup for absolute minimalist and then after testing decide on whether you need to use an external too.
Remember, at 96/24 you eat hard drvie space like its going out of fashion.

For the person who is DEAF.
44K is general purpose recording format and is not suitable for anything of real quality, if you cannot hear the difference I would recommend you go and look for another job.

I have been mixing and recording at high rate for years, and find the only problem I have is the equipments capabilities.
And yes, you can hear the difference between 44, 48,88,96 and 192, even at 54 years of age.

What you really need though is a 16tr 2" tape machine and a desk. You'll need two machines though and 32 tracks on the desk, so you can swap the spools to achieve you 2hr recording time.

Quote chris found:

---

For the person who is DEAF. 44K is general purpose recording format and is not suitable for anything of real quality, if you cannot hear the difference I would recommend you go and look for another job.

---

Without wishing to resuscitate the well-flogged dead horse debate of which sample rates should be used, you might find it useful to research what many professionals users around here use before potentially insulting them all with you first post

Bob

--------------------
www.bickerton.co.nz

Here Here!!

It's so nonsensical it doesn't bear defending. But don't worry too much, if you say you can hear the difference between 44.1 and 48 sampling rate who are we to dispute that. It would take an audio booth, and some clinical recordings (I mean hearing test quality) then we can't argue.

Suffice to say I don't freeeeekin believe you!!!

--------------------
The only excuse we have for making music in the first place is to make it differently..vis-a-vis our own difference (Glenn Gould)

Quote It's Howdy Doody Time:

---

How many simultaneous tracks did you record.

I have a Macbook Pro (first edition) and it really struggles on multiple tracks.

---

Sorry... 16 tracks at the same time 24bit / 44.1 Khz

No sign of strain on the computer at all...

Just noticed that You are running Logic 7, are You sure You are running the Universal Binary version?
(If You were running the PPC version it would def. explain why You have issues...)

Edited by Janne M (13/06/09 02:04 PM)

Quote chris found:

---

Hi
I have been mixing and recording at high rate for years, and find the only problem I have is the equipments capabilities.

---

I'm glad your only problem has been so insignificant.

Forget 96kHz - 44.1kHz is fine, 48kHz if you must.

Have one of these as a back-up (or even the main recorder)...



I wouldn't trust a lappie to capture something as critical as a concert - you're gonna look a right twat when you tell 'em "Sorry guys, I can't think what happened but....."!!!

--------------------
Website / Music Lab Machines / Blog

Quote Jonnypopisical:

---

why 96kHz - I think you (or someone else) is fooling themselves if they think they need to work at this sampling rate. 24/44.1 is more than fine.

JP

---

There's nothing wrong with working at 96kHz IF your system can handle it AND if that is what the client specifies. What happens if this recording's final destination is SACD or DVD-A?

In the right setting, with good monitoring and room treatment, I certainly hear a difference at 96kHz vs 44.1kHz - not so much between 44.1 and 48 or 88 and 96 though.

The HD24 is a very good recommendation but has maximum sample rate of 48kHz.

ken

--------------------
I'm All Ears.

Quote Ken Long:

---

The HD24 is a very good recommendation but has maximum sample rate of 48kHz.

---

I was going to mention this as well. With the optional card, the unit becomes the HD24-XR, very nice and nicer too at lower sr's with the optional converters.

At resellers, I've noticed that the bundle (HD-24XR) seems to be vanishing, and I think the optional card is now less expensive, which points to, perhaps, the coming of the end of availability.

I believe the track count is under 24 at 96k, at least analogue ins, so maybe someone can come along and give an informed answer to that issue.

Quote Jeraldo:

---

I believe the track count is under 24 at 96k, at least analogue ins, so maybe someone can come along and give an informed answer to that issue.

---

Yep, it halves to 12 at 96kHz.

Thanks for all your post guys. I am now leaning towards investing in a standalone HDD multirack recorder for the concert recording. The Fostex D2424LV appears to be a good unit and well respected. However, how would I get the audio from the Fostex internal HDD into Logic to mixdown the tracks? Then I am still worried how the machine will cope with 16 (possibly more) tracks of 24/96 audio!

Thanks, Alex

It's simply a question of importing the audio files onto the hard drive of the Mac, either through firewire/ethernet (if the Fostex has that) or by somehow connecting the Fostex drive to the Mac. You need to start all tracks at the same time so that they can lined up in Logic.

Alex, it would be useful to give us more information about the project. Has the client specified 96KHz? From the information you have given us, you are using the pre-amps on the 8pres, they're OK, but they would be a far weaker link in your recording chain than 44.1KHz! And I'm not sure the converters on the 8pre would do 96KHz justice anyway. Are you using fabulous mics in a fantastic acoustic?

Sounds to me like you're causing yourself quite a lot of pain for zero gain!

Cheers

Bob

--------------------
www.bickerton.co.nz

I wholeheartedly endorse the D2424LV asI have beeb using one for several years and it has never missed a beat.

When in 24/96 mode it will only record 8 tracks simultaneously. I've only ever done 24/44.1 or 24/48 projects with it.

As far as transferring to a DAW for editing you have three options:

1. Connect its outputs to your DAw inputs (Optical ADAT or bal/unbal analogue out) then press play on D2424 and record on your DAW

2. There is a utility that allows the Fostex formatted HDD to be read in a compurt (Can't remember if it was PC/Mac or both). This utility was never updated and was pretty flakey as I recall.

3. There was an ethernet card for the D2424 (Very expensive option) you could add, then you can use any FTP software to transfer the files from the D2424 to your Mac/PC

I used the ethernet card option but if you have enough inputs its way quicker to go with option 1 as the ethernet card is only 10Mb and is really slow.

I am doing the opposite to what you are doing.
I use the D2424LV for location recording and for bands only recording for maybe 15 mins in one go, so I using my Macbook with the Profire lightbridge and 3 Octopre mic pre's to do this. I got fed up lugging the D2424, 3 octopre's a 24ch line mixer around.
Now my rig fits into a 4U rack bag.
The D2424LV will be up for sale after I've done my first real world test.

Lizardpoint

Quote AlexR:

---

Thanks for all your post guys. I am now leaning towards investing in a standalone HDD multirack recorder for the concert recording. The Fostex D2424LV appears to be a good unit and well respected.

---

Be aware again here that the Fostex drops to 8 tracks when recording at 96kHz (if, as most others have mentioned, you actually need it).

Hi, no, the client has not specifically specified 96kHz and I am leaning towards sticking to 48kHz now. I was thinking 96K being fussy and wanting the best! Looking at the Fostex D2424LV and the Alesis HD24 with the EC-2 upgrage card that has SKM converters, improving the quality at all sample rates (and giving a 96k option).

Alex

Are you working with video? If not, then why are you using sample rates tied to video? There's greater potential for cross sample distortion when it comes down to burning it to a CD.

jord

You don't need low latency to record a live concert, so increase your interface's buffer to the highest setting you can (1024/2048/4096 samples) and you'll be able to record more channels without a dropout.

--------------------
www.estudiodrummond.com.br

48/24 makes sense for DVD
44.1/24 makes sense for CD

--------------------
PA stuff on FB

Quote Bob Bickerton:

---

Alex, it would be useful to give us more information about the project. Has the client specified 96KHz? From the information you have given us, you are using the pre-amps on the 8pres, they're OK, but they would be a far weaker link in your recording chain than 44.1KHz! And I'm not sure the converters on the 8pre would do 96KHz justice anyway. Are you using fabulous mics in a fantastic acoustic?

---

Hi Bob-I wonder, though, if there is more to be gained (pun not intended) with "lesser" converters running at higher rates than better converters running at higher rates.

I have some gear that clearly sounds better at 88.4 and then resampled with good software. Other, older gear, running at 44.1, which I suspect has much better everything-including the converters- doesn't sound wanting.

Quote:

---

For the person who is DEAF.
44K is general purpose recording format and is not suitable for anything of real quality, if you cannot hear the difference I would recommend you go and look for another job.

---

Utter bol*o*ks!

Before you go spouting off on this forum about sample rates you might want to listen to the views of a large number of audio professionals who frequent these 'hallowed halls' and learn a little something from people who really know what they are talking about and are not lulled into believing everything that the manufacturers of audio kit might try telling us

Oh, welcome to SOS by the way........

Cheers
Anton

--------------------
You see when I was a young kid Elvis was top of the charts - That's 'Presley' not Costello!

Quote Jeraldo:

---

Hi Bob-I wonder, though, if there is more to be gained (pun not intended) with "lesser" converters running at higher rates than better converters running at higher rates.

I have some gear that clearly sounds better at 88.4 and then resampled with good software. Other, older gear, running at 44.1, which I suspect has much better everything-including the converters- doesn't sound wanting.

---

Interesting point, but I'm not sure. In the unlikely event I'll have several hours to spare one day, I may run some tests.

My standard set up is to use pre-amps and converters (@44.1) on my Focusrite 428 and supplement these with DMP3 pre-amps (soon to be replaced by DAV) and the 8pre.

It would be an absolute thrill for me to be concerned about sample rates! It would mean I was only recording in perfect acoustics with optimum mics and placement, with wonderful musicians who had fantastic sounding instruments, through excellent pre-amps and with wonderful monitoring, oh, and clients who appreciated all the above! Can't wait really!

Bob

--------------------
www.bickerton.co.nz

Quote Bob Bickerton:

---

Quote Jeraldo:

---

Hi Bob-I wonder, though, if there is more to be gained (pun not intended) with "lesser" converters running at higher rates than better converters running at higher rates.

I have some gear that clearly sounds better at 88.4 and then resampled with good software. Other, older gear, running at 44.1, which I suspect has much better everything-including the converters- doesn't sound wanting.

---

Interesting point, but I'm not sure. In the unlikely event I'll have several hours to spare one day, I may run some tests.

My standard set up is to use pre-amps and converters (@44.1) on my Focusrite 428 and supplement these with DMP3 pre-amps (soon to be replaced by DAV) and the 8pre.

It would be an absolute thrill for me to be concerned about sample rates! It would mean I was only recording in perfect acoustics with optimum mics and placement, with wonderful musicians who had fantastic sounding instruments, through excellent pre-amps and with wonderful monitoring, oh, and clients who appreciated all the above! Can't wait really!

Bob

---

let us know what you reckon to the DAVs when you get them Bob.

You are getting them from Mick direct I assume?

--------------------
Matt
www.krcollective.org

Quote chris found:

---

And yes, you can hear the difference between 44, 48,88,96 and 192, even at 54 years of age.

---

I wouldn't argue that it is perfectly possible to hear a difference using some equipment when comparing recordings made at those different rates. Been there, heard it.

But that's not the same thing as saying that 44.1kHz "is not suitable for anything of real quality" which is technically and demonstrably not the case.

It is simply that some converters do not perform adequately at 44.1kHz. Sad, but true.

Hugh

--------------------
Technical Editor, Sound On Sound

Quote matt keen:

---

let us know what you reckon to the DAVs when you get them Bob.

You are getting them from Mick direct I assume?

---

Yes, but I'm afraid they're in next year's budget, I gave priority to live sound purchases this year

Cheers

Bob

--------------------
www.bickerton.co.nz

interesting to see this thread pan out as dedicated hardware over daw

--------------------
Original artwork and unique devices inspired by vintage technology http://www.thisisobsolete.com

So, Fostex DL2424LV or Alesis HD24 with the upgraded EC-2 SKM converters? Both options are very similar price wise. It appears it is easier and quicker to transfer the tracks digitally to a DAW with the Alesis?

As I understand it is possible to reliably run 16 and more tracks at 24/96 straight to a Mac, what typical setup/systems are people using for this (computer spec wise etc)?

Enjoying this thread and excellent reply's - thanks guys!

Alex