I understand Value Engineering... the school I retired from had a 1978 install of 144 circuits in a dimmer-per-circuit configuration with Electro Controls bolt-in style dimmers.
The catch was we only had about 70 dimmers. If you needed to use a circuit without a dimmer, you had to remove a dimmer from somewhere else and install it.
A "future dimmer rack" location complete with conduit for 3-phase feed and load circuits was even provided to expand the system. Today the system is actually dimmer per circuit with ETC Sensor dimming and Ion control.

Ah yes. The community theatre which I am now the TD of used to operate in a similar way. The original installation (ca. 1995) provided 2 ENR 96 racks, but about 40% of the modules were Airflow modules. Always added extra steps to solving "light no workie" issues. If you were an LD with less-than-stellar documentation skills, figuring out which dimmer to steal was also a pain - especially since you had to think about both circuits that went with the pack.

The console was a Status 24/48 which could control all dimmers but only patched to 48 channels at a time. That was easily the biggest Achilles Heal of the system. These days, the theatre is running an Element. One ENR rack has been removed (modules saved) and was replaced by a Sensor rack. The second ENR lives on, with the eventual plan to remove it once LEDs are further established in the space. 24 channels of Echo relays were also added, but wish it was more. I don't love the fact that one entire catwalk is provided with a single 20a circuit. Especially when I want to use one of our VL1100 TSD's. Hopefully ThruPower modules will come in to play when we do our next round of expansions.

The original installation served the theatre well for two decades until any meaningful upgrades were made. The console started getting flaky sometime in the early 2000s (replaced by an Express) and the processors in the ENR racks started dying later on. I believe I have a spare on the shelf - still in its ESD bag.
 
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Not to pull your leg TOO hard; only a little. . .
Like you; I've similar memories of long ago, I'm decent on last month....
Can you recall what you had for lunch the day before yesterday?
Easy. I don't eat lunch. Saturday supper: burgers, rice, peas and carrots; Sunday and Monday: tuna noodle casserole; Wednesday: pizza (homemade from scratch).
 
I think maybe Channeltrack in 1978 was when CMX was introduced.
Was ColorTrack before Channeltrack? (ColorTrack advertised itself as "the first color lighting monitor" when infact, it was a b/w monitor with different gels taped to parts of the screen.) I think both were in the "Kliegl Performer" form-factor, aka Wyse terminal.

I'd have to pour through Let There Be Light and maybe also The Speed of Light and Pathway's Control Protocol 2 pages to be sure, but I think "CMX" (which I call "D192") began back in the Dimension Five consoles/dimmers.

EDIT: From the Pathway site, what a fine sight to see, cited above:
History - CMX (sometimes called C-156) traces its beginnings to an innovative control console called Channel Track that Colortran unveiled in 1979. A digital data stream, sent from the CPU over a coaxial cable, was decoded by a local D/A converter into individual 0-10 volt analog levels. The protocol appeared in its present form in later designs, such as the Patchman, Dimension 5 and Prestige series consoles. These products utilized RS422 differential data transmission for remote D/A's or direct control of dimmers. CMX receivers included a 108-channel D/A card produced in the early to mid-1980s and the popular D192 high-density dimmer rack introduced in 1985. Virtually all control and dimmer products sold by Colortran were user-configurable for either CMX or DMX operation by 1989. As many people in the industry are aware, CMX protocol was the prototype for today's DMX512. The only major difference is the data rate, which was increased to 250 Kbaud for DMX. Interestingly, Colortran's design team foresaw the need for the protocol to talk to more than just dimmers, so they designated the first word of the data stream as an identifier for the type of information to follow (now DMX512's start code!).

Details - Two slightly different transmission speeds were used: 156.25 Kbaud for early systems and 153.6 Kbaud from about 1985 on. There's not enough difference between the two rates to matter, so a controller running at either speed will work with any dimmer rack. CMX pioneered the familiar 5-pin XLR and pinout later adopted by DMX512: shield/common on pin 1, data- on pin 2, data+ on pin 3. Some products such as Status consoles received their DC power from the dimmer pack on pin 5.

Interfacing Hints -- Problems may be encountered if you try to read and convert the CMX output from a Patchman console. This unit sent even parity instead of a second stop bit, which will confuse many receivers. Caution: before connecting new control equipment to an older Colortran dimmer, first ensure that no power supply voltages are present on pins 4 or 5.

So @BillConnerFASTC was correct in his remeberance.

N.B. The last time this site was discussed, I think I remember @STEVETERRY taking exception to something Dave Higgins said about CMX's timing?
 
Was ColorTrack before Channeltrack? (ColorTrack advertised itself as "the first color lighting monitor" when infact, it was a b/w monitor with different gels taped to parts of the screen.) I think both were in the "Kliegl Performer" form-factor, aka Wyse terminal.

ChannelTrack came first. It was the big rolling desk unit. Competed against Kliegl Performance and Strand Multi-Q, also rolling desks. Color Track was designed to compete against the Kleigl Performer (EDIT- corrected - Thx Derek) and was prominently shown in an MTV video of Phil Collins and Phillip Bailey’s “She’s and easy lover”.

The site below has all sorts of cool photos of legacy desks, including something called the Berkeley Colortran System Two.

 
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Thanks Bill & Steve for that site. So we (I've) learned that Channeltrack came first in 1978. ColorTrack followed in 1979, but, the back of the console pictured at

Screen Shot 2020-04-24 at 11.54.04 AM.png


shows only 3 Centronics-style connectors (32 ch. each) for output, indicating analog-only output. Perhaps there was a later generation Colortrack that spoke "CMX"?

The only installation I've ever seen was at a high school in Illinois (Niles West HS) and I'm pretty sure it was connected to D192 dimmers. Wait! perhaps not. I did only one show there around 1989 (a comedy show featuring unknown comics Emo Phillips, Judy Tenuta, and Jerry Seinfeld) and now remember the board in the booth, but not connected to anything. We used the school's Scenemaster60, which I assume replaced the ColorTrack and its dimmers. Nevermind.
 
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The collection at Whitelight is fascinating - I've seen it - it's next to the lighting warehouse breakout area. Some really bizarre stuff in the collection.
 
The ChannelTrack I knew a long time ago had a separate analog output enclosure that was attached to the back of the console and spanned the length at the top. It had a separate fader for each channel. It is possible that the processor in the lower section talked to the output section via CMX. I never saw the output section detached from the console. I think this also predated the use of an XLR5.

One thing I distinctly remember is calling up a cue. The 8" floppy drive would grind until it reached the spot where the cue was stored.
 
Channneltrack spoke CMX between its main processor and its output processor that generated 0-10V analog, The output processor was physically part of the console. Both were designed and built by ETC (at that point simply "those kids from Wisconsin" around the Colortran factory) for Colortran.

Then came the Patchman console (also built by ETC) and the HDD dimmer rack. At that point, the output processor moved to the dimmer rack, and CMX was used to connect the two with a single-pair 5-pin XLR cable. Subsquent Colortran dimmer products received CMX directly, and subsequent consoles spoke CMX. The first Colortran dimmer product that received DMX512 natively was the ENR series, although many D192 packs and racks were converted to DMX512 with a simple hardware change.

ST
 

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