Recording continuously for a month??

[rightintheface]

So the background to this is a uni project I'm working on: I've build an instrument that converts light (as in, optical energy) into pitch, and I want to capture the audio from an entire month of recording it in a static position, almost like an audio Sundial.

My question is: has anyone attempted/succeeded/failed at a super long continuous recording? Obvious hurdles I can see are: computer meltdown, software meltdown, black out, storage space.

What would be the software with lowest CPU drag - Reaper? Would a consumer grade computer (maybe a G5?) explode in flaming glory recording for that long?

The instrument outputs a stereo signal and I could probably get away with 16/44.1 too...

Any thoughts welcome!

[Chinagraf]

Could you record the data coming from the optical sensor (is it a voltage it produces?) instead of the audio, and then convert that to pitch after the fact, so you listen back through the instrument instead of a daw playback,that way you could use some sort of data logger instead of a recording system..?

[rightintheface]

Unfortunately not Andy - the instrument is already built and each one is 100% analogue with no option (or room) for adjustments to the circuit. I like your mode of thought though... thanks!

[wez]

I like the ambition - recording for a month, wow.

Obviously you need to find the weak point or bottleneck, which i think will be the software.

Storage space... not a problem at 44/16, my rough calculations suggest you only need 500GB (even at 44/24 you'll only need 2TB i think?)

Blackouts... you'll absolutely need a good UPS, preferably one that you can monitor remotely.

Hardware meltdown... Any decent machine (like a G5) can potentially run continuously for months, even years. But you may want to consider a server, that's what they're built for. Either way, you'll want to consider running two systems side by side for redundancy.

Software... well this is where it get's tricky. You'll need to find an OS and a DAW that support a single file of this size, and a recording time of this length. you might find some recorders will freak out after 999 minutes (about 16 hours). you'll be recording for approx 43,000 minutes. You'll also need to be recording directly to disk, not into RAM (for obvious reasons). Also, imagine the system falling over on day 30 and taking all of the recording with it! I'd be looking for some way of mirroring the data onto another drive and recording it in chunks in the background... a RAID system perhaps?

I'm wondering - since you only need to record two tracks - if the best solution would be some sort of bespoke Linux setup, recording direct to disk using something like MAX or a simple recording script/routine.

I find this strangely fascinating.

[gigpiglet]

want to hire one fo my joeco black box systems?
should do it no problems...
ive only previously recorded for "days" but don't see why "weeks" would be an issue
happy to test it for you if you like

[Drumstruck]

How about 2 DAWs time sync'd to you mixer - do a day? a week? each with some overlap then swap - join the files at the end of the experiment.....

[Kurt]

I'd go with Gareth's offer but there's no reason to think any PC couldn't do it, Mine, and millions of others, run 24/7 (though I'd want to run two or three, just in case!) I've never tried recording audio for longer than a couple of hours but video software is clever enough to make new files when it hits size limits, surely DAWs would be the same?

[Chinagraf]

Some of the newer RME stuff (UFX) records direct to a usb drive from a socket on the front of the converters. Don't know if it has a record length limit etc, might be worth checking out..

[Alastair Reynolds]

Guys, don't think Music production software, Think Broadcast software. Broadcast stations have to keep a continuous audio log of the last 42 Days broadcast.
Use a Logger program and record at full bandwidth through whatever soundcard you like, just make sure you've got big Hard disks. You don't need a powerful machine though , any old Windows box with XP and 1GB Ram.
I ran an earlier version of Aircheck for 8 years on a PIII 550 with 256M Ram and an 80G drive. I recorded Mono, used ADPCM 4:1 compression, it gave me about 20 days worth. Never missed a beat.
I've used Aircheck from Christian Zillenbiller for all sorts of little projects for yearshttp://www.zillenbiller.de/aircheck/
You can try a demo version first.
or Charlie Davy's "Surelog"
http://www.charliedavy.co.uk/surelog.php
Demo available as well.

Cheap reliable and will produce just what you want.

I haven't played much with Surelog, but Aircheck can be set to save in handy 1 hour chunks.
You'll need about 450GB for 1 month at 48K 16bit stereo

[Drumstruck]

Alastair's post jogged my lateral thought - another option is Surveillance kit - they run 24x7 for years on end and record video + audio.

And I happen to have one for sale (cameras, cables, PCI card) - oh how shameless

[smash]

The other way of doing it is by using a DVD recorder/HDD unit...

We have a couple in the office, and they create a new file every 8 hours... but they can keep recording for weeks on end. I know, because every now and again, someone forgets to push "stop" on one of our units.

Simon "Smash" Ashby

[rightintheface]

Thanks for all the excellent suggestions guys! that's why this place rocks...

I think the most cost effective/reliable would be using a HDD recorder like Simon just suggested... will chew on it this weekend and see what I decide before the calender flips over to october

[caseyrice]

You could also roll your own quite easily using Max/MSP or Pure Data. File systems limits on file size etc still apply but you could portion it off into pieces and restitch easily. PD is free...