I think there needs to be a little more clarifying going on in this thread.
Differences in systems and PSUs:
Most, if not all scrollers require a
PSU (
power supply). The
PSU takes a
DMX input and sends it out along with
power over 4-pin
XLR to the scrollers. There are two common types of scrollers, the "Chroma-Q" style and the ColoRam style. The biggest difference is that they use different pinouts for
power and data.
Apollo SmartColors, Chroma-Qs,
Wybron ForeRunners, and a bunch of powered accessories use the "Chroma-Q" style
PSU.
Wybron ColoRam, and CXI use the ColoRam supply.
These two different styles are not compatible with eachother.
The "Chroma-Q" style PSUs and devices require (or strongly suggest) that you make a loop with the cable. Meaning that you go out from the
PSU,
daisy-chain to each device, and then run a
return cable back to the
PSU. This helps keep the
voltage up on the
line and provides data termination. This is why there are both 4-pin in and out ports on the PSUs. This style
PSU also sends raw
DMX data to the devices. Each device gets a unique
DMX address which is set on each device.
The ColoRam style PSUs do not require to to make a loop. Also, the
PSU does not
send out raw
DMX data. The data stream is translated to a proprietary stream. Each device attached to the
PSU gets an
address unique to the
PSU that it is connected to and the
PSU gets a
DMX starting
address.
Basic Scroller Types:
There are two basic types of scrollers, single string and multi-string. Single string scrollers give you a fixed set of colors, while multi-string scrollers allow you to mix colors. Due to the fact that single string scrollers have fewer moving parts and require less control they are significantly less expensive than multi string scrollers. You also get better transmission from single string scrollers since the light does not have to
pass through multiple filters.
Dual string scrollers, while slightly bigger offer you more color flexibility. You will need more control channels for them, but they may eliminate the need to buy or make new strings for each show as you can mix a large number of colors.
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As for the OP's situation, I would recommend the
Apollo SmartColor Scrollers.
IMO they give you the best for the money. I would suggest that you get the SmartColor 7.5 with the universal mounting plate, which you should be able to get for around $350 each plus $45 for custom strings. These units are light, simple to set up, and quiet. They also come with
Apollo GelShield to protect the string. The universal mounting plate will allow you to use the scrollers on any
fixture that takes a 10" color frame (like a PAR64) or smaller.
You also have to think about where you are going to using the scrollers, not only now, but in the future. You have many options for PSUs in varying wattages. The SmartPower 150 will
power up to 5 SmartColor 7.5s. As a user of these scrollers and PSUs, I have a bunch of SP150s so that I can put scrollers anywhere, and if I need more
power I just use more PSUs. You have to think that in the future you may not use the scrollers in the same place you are planning to use them now.
One of the other things that you have to keep in mind is that there is a limit to the amount of cable that you can use (or the amount of
head feet). This is due to the resistance of the cable. Generally the maximum
head feet per 150W
PSU is about 200'. This means that even if you only had one device attached to the
PSU, you may not get enough
power to it if your cable run is over 200'. This of course includes the
return run. I don't remember the price of the SP150, but I think that it is around $250-ish.
You can control the scrollers the way you talked about with your
ETC Express. If you connect to the 513-1024
jack, you just need to make sure that it is turned on and that you know what addresses it is outputting. I would suggest setting it to output 513-1024. This is the standard
universe 2. This would mean that the
scroller you set to
address 1 the
console would see it as
dimmer 513. On the
Express you would just patch each
scroller to a
channel and then you can control it like any other device, either with a slider or the keyboard. If you divide 100 by the number of frames in the
gel string you should get the percentage increment to figure the center of each frame.
I know that is lot of info, but I think that it should help. It should also help narrow the questioning that is sure to follow.
