[LAU] digital voodoo: master fader should be set at 0db

Monty Montgomery xiphmont at gmail.com
Wed Apr 14 11:12:17 EDT 2010


> what's ironic though is that its now reasonably well documented that
> if the disk drive is in the line of fire when they start to play loud,
> it really will be unable to keep up. this has nothing to do with bit
> rates, but is (probably) caused by the the vibrations causing read
> failures which necessitate a lot of retrys, thus slowing down the
> effective streaming bandwidth of the disk. if the disk is kept out the
> way of direct incoming sound, the issue goes away.
>
> yes, really!

Really?  I've often wondered about that, but despite doing hard disk
recording for the past ten years now (And I've run some very loud
shows where the whole FOH was shaking) I've never had a hard disk flag
trouble with vibration.  I've always used notebook dgrade drives
though... maybe that's the difference.  They all have accelerometers
and actively monitor vibration to cancel it out (and detect if the
notebook is dropped.  0G == park the heads now!)  OTOH, most
enterprise grade HDs do this too, as they're designed to be mounted by
the hundred in a single rack, and that can shake a rack good just from
all the mechanical actuators being shot from one position to another
at highest possbile speed.  If you've ever held a naked drive in your
hand while it's running, those things can kick..

I know my raid box on my personal workstation (8 high speed enterprise
drives) shudders hard when all the disks are slamming the heads around
full-tilt. I feel it in my keyboard six feet away when the raid is
doing a journal flush.  Pro drives don't do 'quiet mode' (one reason
I'm glad to see SSD becoming affordable! :-)

Monty


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