CX Noise Reduction System from CBS Laboratories.

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Decoder Man

Well-known Member
Joined
Jan 19, 2005
Messages
149
Location
Ashtabula, Ohio
Years ago. A friend who operated an electronics surplus store gave me three CX decoders. At the time, neither he or I had any idea what they were. He gave them to me thinking I could use the enclosures for any projects I might be designing. Recently. I began going through my inventory to see what might be good candidates for Ebay, when I came across these three units. On a whim, I listed one and to my surprise received substantial interest from several Europeans. One gentleman provided a link to Wikipedia where I discovered what a CX decoder is. http://en.wikipedia.org/wiki/CX_(audio)

CX is a noise reduction system for recorded analog audio. It was developed by CBS Laboratories, a division of CBS, in the late 1970's as a competitor to other noise reduction (NR) systems such as Dolby and dbx, and was officially introduced in 1981. The name CX was derived from "Compatible eXpansion," a feature of the technique. The CX integrated circuit U2141B was developed by AEG-Telefunken, Germany, in 1982, by the same team who designed the High Com noise reduction system, a broadband compander with typically up to 20 db of noise reduction.

CX was originally designed by CBS as a noise-reduction technology for vynil LP records, similar to the earlier dbx system for dbx discs. CX required a special decoder connected to a stereo system, in order to fully reproduce the CX encoded sound on the LP. However, CX encoded records could also be played without a decoder, with a resulting (claimed acceptable) amount of dynamic range compression.

Relatively few hardware decoder boxes were sold. Making them extremely rare today.

The project was led by CBS Records group vice president Bob Jamieson and carried out by a team led by Dan Graveraux. The label predicted that CX encoding would become standard on all new LP releases but this did not happen. CBS struggled to gain support for the system from other record companies. The process was controversial among CBS executives and unpopular with some artists. Classical guitarist Liona Boyd demanded that the CX encoded version of one of her albums be withdrawn because of perceived shortcomings, even though Jamieson claimed that CBS had the technical means to overcome such objections.

Approximately 70 CX encoded LP titles were released by CBS in 1982 in the United States. In Europe many CX discs were manufactured in Holland with the catalog number prefix "CBSCX". The albums in this series also came in standard, non CX encoded versions. While the implementation of CX with LP's was quite unsuccessful and short lived, CX would later see success as the NR used for the stereo analog audio tracks on LaserDiscs. It was also used for the audio tracks on discs of the RCA SelectaVision CED Videodisc system.

Two of the units I listed sold quickly. The third is still listed on Ebay. If you would care to see what it looks like, check it out.
http://www.ebay.com/itm/331164071549?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649

I have a question. Were any SQ or CD-4 LP's encoded with CX??

The list of LP's encoded with CX is too large to include here. I recommend you go to Wikipedia to see a partial list.
 
Quad was dead in the water before CBS introduced CX. I'm not aware of any Quad CX recordings. Being both a classical fan and owning RCA CED, I'm aware of CX. I have a few classical CX LP's including the Liona Boyd's you refer to, as well as several CX CED's. As a former dbx dealer, it is nowhere near that level of n/r and/or dynamic range. My main system has a dbx II 224. People's jaws drop when I play a homebrew dbx cassette and/or dbx encoded LP.

Like Elcasette, CX was too little, too late.
 
as I've metioned in other threads CX got terrible audio reviews in high end hifi magazines...most noticeably Absolute Sound Magazine who basically said it was sh*t. they gave a list of lp's to avoid ...actually they listed the entire USA catalogue of CX encoded lp's to avoid.this was around 1982/83..I seem to recall one Australian release of "Jo Jo Zep and the Falcons" on there....the Australian release is not CX encoded...It was seen by many as an excuse for Columbia to press stuff on bad vinyl and get away with it, by using the noise reduction system to mask any pressing faults.
 
Columbia and RCA had lousy vinyl throughout the '70's, and into the CD age. Their 60's vinyl was very good.

MoFi, Sheffield, Telarc, as well as EU and Japan imports showed audiopiles (sic) like me what a 2ch LP pressed on virgin vinyl and CD-4 vinyl COULD BE. Through a powerful amp (250 w.ch), and a Moving Coil cartridge, the analog LP experience never had better fidelity.

And, yes, CX was shit.
 
("to my surprise received substantial interest from several Europeans.")

The first unit I sold went to a fellow in Florida. I was surprised because all the inquiries I received were from Germany. Ultimately, I sold the second unit to a fellow in Germany.
 
That is good to know! Thanks i will make sure it hits the German market, i have 3 of these to sell. I collected a bunch of cx lps and it started with a pile of white label test pressings i got from a guy in Seattle years ago. I found 95% of the CX pressings are from Europe, and those can sound OK. In fact a ton of presings in early 80s are cx encoded over there. It is not as good as DBX but these boxes are not exactly high tech gear. I think it is time to get all this stuff ebayed also, so soon if interested i will have on my urban liquidators ebay account, a bunch of these lps and these decoders. I remember one test was a moon martin. There was more, a few classical ibelieve. I remember setting it up and listing to a few of the Europe pressings, Jimmy Cliff i remember, and it was ok. I think a dude into circuits and soldier would find some improvements easy to do, and would make one of these boxes quite a bit better. It would be good to do to play the LP THE WALL from pink Floyd. Here is cx info


1.jpg2.jpg3.jpgintro.jpgintro1.jpgintro.jpg100_7588.JPG100_7591.JPG

("to my surprise received substantial interest from several Europeans.")


The first unit I sold went to a fellow in Florida. I was surprised because all the inquiries I received were from Germany. Ultimately, I sold the second unit to a fellow in Germany.
 
One of the interesting things i gleaned from cbs release is that it was worked on by Dan Gravereaux who i interviewed a couple times. He was responsible for SQ since the start.
 
("to my surprise received substantial interest from several Europeans.")

The first unit I sold went to a fellow in Florida. I was surprised because all the inquiries I received were from Germany. Ultimately, I sold the second unit to a fellow in Germany.

I finally sold the third unit to a fellow in California. Just to let you know. The first unit sold for $5.00; the second, in original packaging, $39.00 and the third $10.00.
 
I did some work recording the CX lps over last few days. Got one decoder set up after i had to pop it open and tweak the pot on the back. The pots are not really secured, just hard wired to the board. Gotta set them correct though. I pushed it a bit too hard and had to open it to set it back in place. It would be interesting to chat with Dan about this decoder, he has to be getting really old or gone. Following are pics of the decoder. It measures 12 inches by 6 inches by couple tall. I have to say after getting it set up correct, it is not a lot different than DBX. I think it does do one thing better, it lowered the noise floor to absolute nothing. I can not hear a thing and it shows nothing on the computer file before the music starts. It might not tweak the other way quite as much, which may be a good thing. I did not feel that slight unnatural pop of a snare you sometimes get with dbx. The USA CBS pressing sounded good. The lps from Holland and Germany sound damn good. It was not difficult to find the Holland lps as i remember, as the Holland Lps have CX at the start of the LP numbering. And there seems to be lots of those. Another fun tidbit is the photo of the wax. It says HI DAN HI LOUIE. If you look at the paperwork above, these were the 2 guys responsible for CX at CBS. It is in the wax of the test pressing i posted. If anyone is interested i could put an lp on dropbox after i decoded and recorded. I am recording these in 24/96 so you would be best to pop it on a dvd or a thumb drive. Just did a Moon Martin and Clash and Loverboy and Romeovoid, and Men at Work, and Lacy Dalton and PF the wall.

100_7595.jpg100_7596.jpg100_7598.jpg100_7602.jpg100_7603.jpg100_7594.jpg.
 
Tad, are you saying that the dbx noise floor is NOT silent? :yikes My experience is quite different. I've made hundreds of dbx cassettes and own dozens of dbx LP's. The only noise I've experienced is source noise from the master tapes.

Thanks for the pix and discussion of CX.
 
No not at all, I got rid of all the dbx gear a fear months ago, so it was all by memory, which is suspect, as Sir Paul says, memory almost full. I could pop up a few dbx titles I have on file and I bet they sound quiet also. I was just a bit amazed I imagine!
Tad, are you saying that the dbx noise floor is NOT silent? :yikes My experience is quite different. I've made hundreds of dbx cassettes and own dozens of dbx LP's. The only noise I've experienced is source noise from the master tapes.

Thanks for the pix and discussion of CX.
 
No not at all, I got rid of all the dbx gear a fear months ago, so it was all by memory, which is suspect, as Sir Paul says, memory almost full. I could pop up a few dbx titles I have on file and I bet they sound quiet also. I was just a bit amazed I imagine!

Hi, just came across this tread. I live in NYC and out of curiosity set up a CX system a few years ago (I was investigating various encode-decode systems as part of my reel to reel hobby). I now have a Telefunken decoder (from Germany, which is also a phono preamp). It is more of a curio, as the record selection is small, unlike DBX (or Quad). In any case, I would be interested in buying what you have and you can be assured your collection will have a very caring home. Please send me a pm.
 
Got the CX bug and looking for outboard CX decoders and CX encoded vinyl.

If you have some CX stuff lying around that you no longer want, please send me a pm with your price.
 
While record picking at a local radio station fund raising record sale this past weekend, I tripped across my first CX encoded album: Annie (Original Broadway Cast). The only reason I paused on it was because I recognized the gatefold cover, and it still had shrink wrap on it, so I figured it might be a better condition cover than the one I have. I pulled it out and lo and behold, it had a CX sticker on the front, and back. I believe this may be the first confirmed CX encoded quadraphonic record. We'd have to compare quadtrade's scans above against Mark Anderson's discography, to be certain that there's not another candidate hidden in that promotional list.
Annie CX encoded front.jpg Annie CX encoded rear.jpg Annie CX encoded label.jpg
 
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