Hard Drive (RAID) Question

M

Mark H.

New member
OK, this is probably a very stupid question based on wishful thinking. I apologize in advance if this is the case.

If I understand correctly, *one* of the things that needs to be addressed in order to make top-quality computer-based recordings at 24/96 is that you need a big, fast hard drive to lay down multiple tracks and so-called "zero latency" in order to monitor what you're doing in real time. Is that correct so far?

So one way to address that need is to get something like the Medea AudioRack LP Series RAID arrays, which provide multiple drive units with 80 to 300 GB of storage space for around $2000 to $3700 respectively.

However, if you jump from your on-line audio store to your on-line digital video store, prices for Medea RAID drives for digital video are priced at about HALF the cost per GB of their audio counterparts.

Assuming (I always worry when I start a sentence with that word) that to my computer a Medea VST SCSI RAID drive is going to look the same whether it's intended for video or audio or word processing or any other data-storage task, WHY would anyone spend TWICE as much on the "audio" version? Yes, the audio series comes in a sleek 1U rackmount unit, while the video version comes in an oversize ammo box, but surely appearance alone wouldn't account for the audio version being twice as expensive, would it??

See for yourself: the first link is to the audiomidi.com site, where they're selling the Medea AudioRack LP 80 (80 GB VST RAID) for $1999 and the AudioRack LP 160 (160 GB VST RAID) for $2199.

http://www.audiomidi.com/hardware/audio/drives.html

The second link is to the Video Guys site, where they are selling the Medea Video RAID 2/120 (120 GB VST RAID) for $999, and the Video RAID 2/160 for $1299.

http://www.videoguys.com/videoraidscsi.html

Since digital video requires very high throughput (and the Medea video units provide "30 meg a second sustained transfer rates"), is there any reason their Video RAID wouldn't be just as good as their AudioRack Series for recording 24/96 audio?

I know all you pros are rolling in dough and want your racks to look pretty, but a thousand dollars still makes a difference to me. ;-)

Also, if 24/96 stereo audio requires about 34 MB of hard drive space per minute, the Medea 2/120 Video RAID drive would hold about 58 hours of 2-track audio at a cost of about $17.25 an HOUR. I don't think you can roll tape at 15" per second for anywhere near that price, can you? And if not, these Medea Video RAID units are a tremendous bargain.

"A tremendous bargain" is another phrase I wince at when I hear it coming out of my mouth. I figure I've 1.) made some stupid arithmetic error that invalidates everything I've said; or 2.) there's some technical reason that an audio recordist can't use a SCSI array intended for video.

I'll sure be glad when I understand enough not to be a total Newbie any more.

Humbly and with cap in hand, I await your reply.

Mark H.
 
Bargain my ASS!

Seems to me that using 4 IDE drives at $120 each (>40GB) in a RAID 0 (Redundant Array of INEXPENSIVE Drives, totally striped to maximize throughput) array with a MB or IDE interface that supports this (>$200 extra cost- I think not) could provide 40 MB/sec sustained throughput for the cost of the drives plus the cost of the interface.

Adding $100 bucks for a big case to house the drives and the longer cables that will be required to connect the RAID array to your MB: My total is at $780.

I haven't run into a need for that kind of throughput, but then I wouldn't need a "need" to drool over that kind of performance.

Aside: Question to the GURUS out there.

If you have a second tower to house RAID drives, what is the standard connection to the main MB using them? Seems plenty jerry-rigged to run a ribbon cable through a tower case with the cover left off both units to allow access.
 
The advantage of RAID-0, properly implemented, is simply high bandwidth. Ideally, you will have one controller per drive. Will this be simple? I have no idea. That may be the selling point of the Medea product, that it masks this complexity from the user. Your paying for transparency and support.

If it was my money I would go with a Seagate Cheetah 15,000 RPM 36GB SCSI drive (ST336752LW) with a transfer rate of up to 69MB/s for $600 and add as I needed the space.

Forgot to add this...

Regarding the video vs. the audio version.

Bits are bits are bits. What this means is that only the specs matter, not what you put on the drives. The SCSI drive couldn't care less if the one and zeros came from a video camera or a guitar.
 
Mark - I agree with Doc, you don't need the output of a RAID0+1 system in a DAW. 24/96 wave files are288k/s so you'll get plenty of tracks. Enough to choke the rest of the machine before the HDD is starting to matter. This assuming that you have a modern 7200rpm IDE or better. (No, SCSI isn't better than IDE for a DAW.)

"Zero latency" (apart from being a dream) has nothing to do with your HDD. It's a matter of soundcard, soundcard drivers and processor.

Doc - I've never seen an external HDD case with anything else than SCSI connectors.

/Ola
 
Thank you ola, wheel, stawl and others for your suggestions. I had been working for 36 hours straight when I formed my question. I'll try to keep them shorter in the future. You answered my question very well.

What I need at this point is a comprehensive, practical primer on digital recording on home-level systems. Most of what I've found searching the web so far either assumes the reader is already using a studio-based DAW or provides the $279 bundle that will "create a complete recording studio in your home."

Can anyone point me to a website or book that takes a step-by-step approach to building a computer-based system that is reasonably current?

For instance, my home computer is an Acer box, PIII at 733, 256MG Ram, 20GB hard drive, and reasonably fast performance. If it has a sound card, it's whatever came with the box. I assume that whatever is already on board is basically worthless for quality recording or editing, is that right? How would I figure out what sound card to buy for such a machine? Do sound cards become obsolete as quickly as computers?

After-market sounds cards seem to range from under $100 to well over a thousand dollars, some with seemingly similar specs despite large price differences, some with external boxes, some with AD/DA converters (or do they all have these?), some with 24/96 "capability" (but does that mean they have converters?), etc. It's overwhelming, since the manufacturers' statements seem to obscure as much as they reveal ("true 24 bit processing" -- what does that NOT tell us?).

I'm more than happy to hit the books, but this stuff is changing so fast that I figure my best resources will be on the web. If you can point me towards an education on this, I'd be most grateful.

Sincerely,

Mark H.
 
Step by step instructions:

1. Figure out your recording situation/needs. How many tracks will you be recording at once? Will you be using an external mixer/preamps. Will you need more than two outputs (e.g. to port several tracks to an external mixer)

2. Buy the gear that suits your needs;)

The hardest thing is really to figure out what you need. Will you need to close mic a drum kit with 8 mics (and thus 8 simultaneous inputs), or are you perhaps planning on just recording one track at the time?

So, the three basic questions are:
What type of music will you be recording,
How many ins and outs do you need,
What's your budget.

I'd say that you found the best rescourse on the net already. I think here is the best place to find the answers, because it's not a step by step manual written by a manufacturer who wants to sell you his stuff, or one persons opinion on how to do it - it's a bunch of really knowledgble people who can answer all your answers.

Just my two cents

/Ola
 
IDE cables can only be so long. The limit is somewhere around 2 feet maybe less. just get a big case. I've seen some really nice cube cases that have something like 6 bays beside 6 bays for a total of 12. That gives you tons of room for 4 RAID HDs and a few burners(for duplaction) and a system HD.
 
Thank you all for the good advice. At this point, I'm looking for highest quality sound on a maximum of two channels in and out -- very purist, very minimalist.

Content to begin with will be spoken voice lectures for distribution, voice-overs, possibly some freelance reporting for radio, and radio drama work. Music, if it happens, will likely be mid-sized hall classical and choral.

Although many people assume lower fidelity is "good enough" for speech, I'm actually wanting to buck the trend and bring top quality to spoken voice recordings.

As I gain more experience, I might change my approach, but I don't want to start with a huge, processed mix and get lost in all the potential variables. I'd like to get the basics right as I learn.

I will check out the sources cited.

Many thanks to all who responded. You're the best!

Mark H>
 
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