Random notes.

1. When you use your DCX, follow proper audio system power up and
power down sequencing so you don't send transients to the drivers
that may harm them {usually tweeters}.

Power ON audio system;
1. Turn on sources first
2. Turn on the amplifiers last

Power OFF audio system;
1. Turn off amps first
2. Turn off sources last

If I don't follow this procedure and turn on the amps first,
then DCX, you get a popping sound that can damage sensitive drivers
like ribbon tweeters. Mids and woofers should be ok. I don't know
how robust the new Fountek composite ribbon is vs. aluminum found on others, but people have reported ribbon failure because of these
transients, etal.

An array of expensive ribbons blowing up wouldn't be sweet. If you
are ultra paranoid, some folks install a capacitor on each tweeter
in series to help with some issues manifesting {DC offset, etc},
I've been using fuses on my tweeters for a long time because I'd rather blow a fuse than an expensive tweeter. Fuse value is a variable depending on how hard you drive the tweeter and how sensitive it is to failure. Typically though, I may use 3/4A to 1A
AGC fast blow fuses with an inline fuse holder. {oddly enough,
the fuse spec sheets show the 1A blowing first than the 3/4A, lol}.

http://www.electronix.com/catalog/images/agc.jpg
http://www.mpja.com/pictures/4477.jpg

Maybe you can do a test with one tweeter, install a cap and fuse
and do some listening tests. I usually would start with a lower
amperage fuse, lets say 1/2A or 5/8A and run the system at normal
levels. If the fuse blows early, step up in value. If the fuse holds
up well, but blows when you crank it higher, then you are very close
to finding the optimum size. Pick a capacitor way outside the
intended crossover frequency range, ie if you cross at 2khz, find
a cap that crosses 1khz or less, polypropylene is nice, electrolytics arn't.

2. DCX can store setting in memory locations. This is a powerful
feature. I have 12 setting for my line array. These settings are
not required, you can just set up the system and leave it alone
or you can do something different because you can. I made a
methodology and programmed this into the DCX where setting 1 would
be a 'mellow' setup and gradually gets more aggressive in sound
up to program 12. You start with a baseline and change some settings
like crossover frequency, gain, EQ, etc, in small increments that
allows you to customize the sound for different situations. It's
kinda neat.

Here's how it works. Suppose you program five settings. Your friend
comes over and wants to audition the array. His taste will be
different than yours. To maximize his listening experience, you want
to find out which setting he takes preference too.

Load program 1 and have him listen for a minute or less. Then load
program 2, repeat. He will tell you 'I like setting 3 the best'.
His listening experience will be better because for some reason unknown, it just works out that way and he's happy. Your line array
is more successful in spite that you my like a different setting.

Jedi mind tricks

Each tweeter with its own 1A fuse

vs.

One fuse for all tweeters - This is risky. An eight tweeter line
would need a single ~8A fuse to protect the line but each tweeter is
at risk because it takes much less than 8A to blow the tweeter.
It's very cheap in cost to install one fuse per tweeter so why not
use this method.

I will say that I've not had any ribbons damaged in the arrays including the older JP2 version. The CD2.0 has a different termination which is more robust so if my guidelines are followed everything will be fine.

If I were you, and you are really concerned, I would consider an electronic circuit breaker with nano-sec response time on the tweeter parts of the array. There are places that build these, and failing that there are a number of EE types on the PE forum who could design one for you and you could put it together.

I would be happy to find one of those guys for you if you wish. He'll charge you for the design, but it would be worth it, and you could always make a bunch and sell the rest to the line array world. I'd be interested in purchasing one myself.

Marlboro

Marlboro

A couple of amps.....pay off my college loans. Decisions...decisions.

GEEZ! for $6200 the amps better be more than excellent. They should serve me dinner three times a week, tie my shoes in the morning, and snuggle up to me erotically on cold winter nights. Do they do that?

DM