RSync PI anyone?

I have a fairly slow and noisy 2TB external drive, and recently bought a 3TB drive as a backup drive. I'm using an iMac so Time Machine is handling the backup for me - all is good.

Here's the problem - my home studio has this constant background noise of the 2TB hard drive, so I've decided to move things around a little. I hadn't really noticed, but I've started recording ta 48KHz, 24 bit, with a Rode NT1-A and it just picks up this noise when you have sensible gain levels on the mic.

Further to that a little speed test surprised me - it showed that my trusty Iomega RAID drive is only doing about 30Mb/s write speed. That's ok for recording, but the new drive (USB3 in a USB2 slot as the Mac doesn't have USB3) is writing at over 100Mb/s. Hmm.

So it feels like I should do this the other way round. Have the relatively quiet, fast drive as my recording drive and the slow noisy one as backup. That's the easy part. How do I get the noisy machine out of my studio?

The answer is to put it on the network, connected to a hub upstairs (where I already have a hub for the PS3 and so on). That's easier said than done, given that it's formatted with HFS+ and reformatting in something a NAS will understand will almost certainly lose some information. I need to use HFS+ or something that supports everything HFS+ supports, such as the Linux ext4 format.

I researched ways of putting a non-NAS drive on the net, and there are solutions, but they all seem a bit of a compromise for the £0 I want to spend doing it.

The answer? 

I have moved my Raspberry PI upstairs (powered off the telly - currently - I'd best deal with that), and will connect the Iomega to this thing, formatted as ext4. I can then use rsync over ssh to pull the files from the iMac that I want to backup (I could do a push, I suppose but I'm also pulling some stuff from offsite servers so it keeps all the rsync jobs in one crontab if I pull).

Perfect - I can't use Time Machine, but rsync is great.

Rsync

For those that have not used it rsync is a command line utility in just about every unix - OSX included - which syncs two file trees. These trees can be local or on a variety of different network endpoints, including ssh - perfect for my needs. When run with the -a flag (archive) it preserves file permissions and symlinks and so on.

The really great thing about rsync is it only copies files that it needs to, and in fact only copies "parts" of files that it needs to - brilliant for syncing large files. There's no version history, but I don't really care about that. I just need my files somewhere safe.

Crontab

The cron table is an ages old mechanism for unix machines to run the equivalent of Windows scheduled tasks. The table consists of an interval specification and the command to run. It's fairly straightforward.

It's true that data throughput speeds on a Pi aren't that great, as the network interface is on the same bus as the USB, but again, it doesn't really matter.

The final part of this is to run rsync in the crontab, and use the 'nice' command to lower it's execution priority. I will then set it to run overnight, so it doesn't try to read files while I'm recording.

I'm still copying files to my new fast drive (and will be for hours yet - about 15 hours to copy 2TB it seems). Once that's done I need to move the Iomega drive up next to the Pi, and implement the rsync - then I can leave it to it. 

This means that little £30 pi is running a webserver, sshd endpoint for me to do secure tunnelling into my network from outside, dhcp for my network (because the virgin superhub is crap at it) and now is in charge of my backups. Genius!

Motu 828x Thunderbolt / USB audio interface - a review

So I have taken posession of my new Motu 828x. I wanted to upgrade my trusty Edirol UA101 to something which can be properly plumbed into my home studio, and I take the UA on the road all the time.

I'm not a professional reviewer, but this is a new model of soundcard and one of the few taking advantage of Apple's new Thunderbolt technology. Thunderbolt is taking over as the defacto interface for high end use on Apple kit. It allows six devices to daisy chain, with a full duplex 10Gbps connection to each, which outstrips Firewire 800 (800 Mbps) and USB3 (5Gbps). This means that I hope to have future proofed my studio a while.

True the pro studios are using ethernet these days, but this is a hobby for me, so I won't be going that route any time soon.

So, what do you get with one of these things? Well, as well as two combi inputs on the front for easy access when using guitars and so on you get 8 balanced TRS ins and outs, ADAT, SPDIF and MIDI. I probably forgot something, but the main thing that you might think is missing is the XLR Mic inputs - it has only the two combi inputs. But that's perfect for me as I'm going to use my Focusrite Octopre with this, so I have that covered. This means they've spent on the money on internal quality, and things like an effects unit, rather than Mic preamps.

In the box you get the unit itself, with ears for attaching to a rack, the power cable of course, a USB cable (bit of a shame - have to get the Thunderbolt cable for yourself) and the drivers. You also get AudioDesk software, which I'll review separately if it's any good. I use Logic, so not sure what I'll use that for.

 And here it is installed above the Octopre in my desk rack. For the nostalgiac that's a JV-1080 underneat the Octopre. I've wired it to have 4 of the inputs from my Octopre, as I never use more than 4 at a time anyway, with the other four from my two modules - the JV and an aging TG300 which, to be fair, I don't use often, but it's a quick way of getting Sibelius to sound decent.

My first barrier is that the drivers were shipped on CD, but fortunately I have an external Blu-Ray player so I can get it installed.

As seems common for sound devices, even on a mac, a restart seems necessary (I wonder if it actually is...) After a reboot and checking the settings in the dialog which auto opened I fired up Logic and let's see what we've got...

So, first impressions on the sound quality are as good as you'd expect. Certainly the clarity through my little Yamaha MSPs is excellent, not least because I'm able to use the XLR inputs and not the jacks, so the tiny little bit of mid range distortion, which I thought was the monitors, has actually gone. The bass is just ever so slightly more reinforced too. Lovely!

Using the Audio MIDI Setup tool I was able to see which inputs in logic correspond to which inputs on the device too. It's as follows:

1/2 the combis on the front

3/4-9/10 the TRS jack inputs on the back

11/12 reverb from the inbuilt effects processor, so you can track this on a separate track - neat

13/14 the FX return (did I mention this thing has an insert on the back too?)

15/16 SPDIF (I have my DAT connected to that)

17/18-23/24 ADAT channel A

25/26-31/32 ADAT channel B

That's one hell of a set of interfaces. From the blurb it looks like you can run the whole thing at 192KHz (assuming you have the processor for it which I don't) but there's something about the SPDIF maxing out at 96KHz if you use 192KHz on the ADAT. I suggest if you're going to be using high frequencies on the ADAT you read the tech specs.

So, the next thing I did was rename the I/O Labels in Logic and save this as my default template.

I noticed that the sample rate was set to 44.1KHz, and I prefer to work in at least 48KHz. When I tried to change this in the MOTU Audio Setup it changed it back, and the clock light on the front of the panel flashed a few times. I thought it might be because I have a DAT connected, which will have whatever frequency I recorded on that, but turning that off didn't help. One nice thing this device has over my UA is that it seems to be able to change frequency on the fly. The UA actually had a different device for the different frequencies, which meant it was a pain to change between interfaces as you had to power cycle the unit. This doesn't seem to have that constraint, so why can't I change the frequency?

Well, it turns out it's Logic is doing this. I'd not seen this before because in my other device, as I said, the setting was provided from the hardware, but in the Audio options in logic there's an option to change the sample rate. This looks per-project, but I can change my default template to support this I suppose. As it happens, this project was recorded in 44.1 - if I open one that was recorded at 48KHz I guess it would switch. Funnily enough, though, going through looking for a project recorded at 48KHz I can't find one - which means something funny was going on with my last sound card. It looks like even though it had a hardware setting of 48KHz Logic was downmixing this to 44.1 in software or something. How had I not spotted that before?

Sorry about the picture quality - I'm writing this on my ipad using the camera rather than taking screenshots, which would be way more professional, but I wanted to record how I'd got this running right, and this is the easiest way of doing it.

I have a recording day coming up with a barbershop quartet soon and I'm keen to see what the latency is like on this new kit, so I shall post anything interesting. Meanwhile, please feel free to drop me any questions you might have about this device. I got this one for a little over £600 from GAK (with some free headphones actually) but I think the retail is closer to £799. It's definitely a step up in capability for me, and there's lots of potential in this little unit.

Devout or fundamentalist?

An article on Radio 4 this morning got me thinking and I thought I'd share. 

It's interesting when two words which apparently appear very similar in meaning get used to refer to different things. Take, for instance the phrase coined after the London 7/7 bombings by a passer by commenting on emergency measures. She said "we should be prepared to give up some of our liberties for freedom". What does that even mean?

What she meant was civil liberties within our borders and freedom from oppression from without. 

The article this morning made me think of this phrase again. The Muslim being interviewed took offense that being a good catholic is to be devout - which is seen as a good thing. But a devout Muslim is labelled 'fundamentalist' which is seen as a bad thing. 

I think I agree that these are inconsistent but where my thoughts differ is that I think both are bad. The closer you get to the 'extreme' end of a religious spectrum the more dangerous you are, and I don't think it matters much which religion. Compare the Taliban with Christians in the Bible Belt. Both groups use an extremely fundamental view of the world and force this world view on those around them. 

The Old Testament and the Qu'ran both have some pretty gruesome teachings (some of the same stories actually) and moderates leave out the bits which modern society deem inappropriate or just silly.

Of course the old stories are good if you're racist and looking to back that up, or if you think women shouldn't drive or own property. Again, society hasn't quite made these inappropriate or silly just yet but I'm optimistic. 

For now I'll remain a devout atheist, dedicated to the rational and logical analysis of our world and our behaviors within it.