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Re: Firewire vs USB (WAS: Packing a laptop setup (with trombone) into bags)

Hey Luis,

> Ive actually been quite happy with it,but the recent problem with my 
>firewire problems also made me realize how fragile this things are and 
>think what if that happened while i wes traveling or at a gig.
> I still dont know what went wrong,if it was a FW cable that burned my 
>PCI card,RME,Presonus and macbook FW port,then i d be terrified to do a 
>tour with this,
> i didnt know that a FW cable can cause such damage!

In that ruggedness discussion, I sometimes get the feeling that people
compare things which can't be compared with each other properly. If
you take as an example a musician who uses a setup of stomp boxes or
rackmount effects, you'll usually find them mounted into shock-mount
rack cases or specific cases for pedal boards, with everything screwed
firmly in place, cables of fitting length tied together neatly etc.
And these devices are constructed and made to be subjected to the
perils of life on the road and to last for a long time.

If you take a macbook, on the other hand, this is definitely not a
device designed for life on the road, much less to last for a long
time. As typically people tend to get a new computer every two years
or so, this is  the life span they target, and as most people usually
have them either sitting on their desk or packed neatly in a stylish
laptop bag and don't have them thrown by roadies etc., they will last
for that time span. And finally, they are not made to be used in some
kind of "fixed installation" (with all the cables permanently in
place), so cables just come out at all ends - and to keep it cheap,
cheap implementations are used for connectors which were designed
cheaply in the first place.

Mounting a laptop into a performance rig is one of the things that are
as of now unresolved in my opinion. Although I've finally settled with
integrating a laptop (as opposed to, say, a rackmount industry PC)
into my rig, this is still the weak point of my setup. There are no
mounting screws in my laptop. Connectors come out on different sides.
Etc. etc.

So if you'd compare (reliability of) computer-based solutions to
stompbox/rack effects implementations, you'd need to consider computer
made for being on the road: embedded/industry computers which adhere
to the higher protection classes - together with fitting
keyboard/pointer and screen, and mounted firmly in a rack.

Still, by using prudent wiring, I think I am able to avoid things like
firewire cables breaking. And besides, I don't power my firewire
interface via the bus. Which brings me to your question:
> But what about a bus powered FW soundcard like the RME FW400 or other?
Simple: use the external power supply!

> i guess there is no other way around it,wether is SW or HW you always 
>need a backup.
I was just thinking about that other post I read the other day where
someone said "Have you ever heard of someone who brings a computer in
case his pedalboard fails?".

Seriously, although from most of our experiences it seems that
computer setups more often tend to have a complete failure, it's not
just that.
When doing fault tree analysis, you usually consider for a system of
several components a) how big the risk is that this specific component
fails (as a sum of its different means of failure) and b) how hard
that affects you.
And when we look at the comparison of the three main setups we tend to
see - A) pedalboard setup, B) rack setup, C) computer setup, and leave
your instrument(s) out of the consideration for one moment, it's some
like this.

A: Failure risks for all components are more or less equal and not too
high. What's more, usually none of the components is that pivotal and
thus is a showstopper (with the possible exception of a central PSU) -
meaning if your coveted MXR 90 phaser fails, you can simply patch
around it and continue nearly unaffected.
B: There is usually one pivotal component: the mixing console. For
that reason, some people tend to bring a spare power supply for bigger
consoles, because that seems to be the pivotal component that's most
likely to fail (a single channel failing won't hurt you that much).
C: So you have your computer, your interface and some means of MMI. If
the computer or the interface fails, it's over. Completely. No audio
without the computer or the interface.

So as in C the risk of a single failure as a showstopper is the sum of
the individual failure rates (as a number between 0 and 1) of the
components, for A (if we assume that you have to stop if three pedals
are gone) it's the product of the individual failure rates. In other
words, if the failure risk both for a single stompbox and for a
computer or interface was equal (which I'm not claiming) and 0.1 (10%,
which I'm not claiming, either), then the risk of a complete breakdown
was: for the computer 20%, for the pedalboard 0.1% which is 2000 times

What do we learn here? Change your computer setup so the single
components aren't showstoppers. E.g. use an audio interface which
allows for standalone operation (like your FF400) in combination with
an additional simple effects device which would allow you to get
going, and have adapters ready which allow you to work with your
computer's integrated soundcard. Whoops, the cumulated failure rate
has dropped from 20% to 1%.