JVC CD-4 demodulator 4DD-10

[rherber1]

I recently picked up a Technics quad (It is in another post) But i got this also, A JVC CD-4 demodulator 4DD-10. I have never used one but thought it might be good to have with the Technics. Any info on this would be great. ThanksView attachment 32046View attachment 32047View attachment 32048

Hi,
Like yourself I have a JVC 4DD-10 CD-4 demodulator and I am also trying to locate documentation relating to it. Apart from your post and a German web page http://www.hifimuseum.de/cd-4-quadrophonie.html (see Chronology section) I have found no other mention of the 4DD-10. According to the Chronology the 4DD-10 was released around March 1972 and the 4DD-5 around June 1972.

 

[bigbillquad]

Hi. All

I have found one off these JVC CD4-10 demodulator on the Japanese Auction site if anyone is interested....

( https://www.jauce.com/auction/o338007138 )

 

[rherber1]

That's the first I have heard of this model. However, it is not the same as the 4DD-10.

This page gives some details of the CD4-10 https://audio-heritage.jp/VICTOR/etc/cd4-10.html (it's in Japanese so you will need to use the translation function in your browser)

 

[Circular Vibes]

Hi. All

I have found one off these JVC CD4-10 demodulator on the Japanese Auction site if anyone is interested....

( https://www.jauce.com/auction/o338007138 )

View attachment 43009

The CD4-10 can be upgraded to a CD4-10S (Studio) but I haven't tried it yet. Here is a link to the original auction page. Victor CD4-10 The 10s don't come up very often and are usually a bit rough to look at. I see it is listed as a CD4-1, an earlier version.

 

[Cyber 1]

I have a Pioneer QD-240 CD-4 demod available

 

[The Quadfather]

I imagine a demodulator sold under the name "Victor" was flying under the RCA flag. RCA was the American counterpart to JVC. RCA picked up the "Victor" name when they bought out Victrola. RCA made all kinds of electronic things. I spent a good part of my career maintaining an RCA television transmitter.

 

[furui_suterioo]

Just got an old 4DD-10 demodulator today, cleaned knobs and button with deoxit and it seems to be working ok, it's been on for about an hour now, seems to be more sensitive to sandpaper than my built in kenwood demodulator. Still able to demodulate through built in decoder in 2ch-disc mode but with slight distortion, my current cables are from the dollar store so that will definitely have to be improved right away. Here is the front and the under side:

 

[EmeraldCity]

Your pictures today of the 4DD-10 reminded me to finally find and unpackage my 4DD-5 I received directly from JVC back in 1972. Pics attached. May I share how I got it (pretty self indulging)?

I went to Yokosuka, Japan in Sept 1971 as a lowly Radioman with the US Navy. I didn't fit in very well with what the others were doing. I built some furniture including some speakers and bought a set of JBL C36-030 speakers. I visited Akehabara where all the stereo stores were and was blown away by all of the new equipment. There was a stereo store a couple miles from base that I frequently visited and became friends with a JVC Rep. Late in 71 or early 72, I was taken to the newly opened JVC testing facility that had several test chambers: (1) one that they could delay echo by up to several seconds by moving the walls, (2) an anechoic chamber (completely dead room - I remember turning away from my friend - he yelled and I could not hear him. We walked on a metal woven grate suspended in the center of the room), (3) a recording room, (4) a performing room, and maybe others, I don't remember. I was shown their newly developed CD4 system. They sat me in the middle of a room with only speakers in each corner. I remember being so stunned to hear 4 guitars clearly and individually coming from each of the 4 speakers with what seemed like NO overlap. A month or so later, I was hired by them to review their literature and clarify the English. I can't remember how many I did but couldn't believe how many models one company could produce They had also just released their line of SEA (Sound Equalization Amplifier) equipment. Besides the money they paid me, I was given some stuff. The pictures attached were of a 4DD-5 I was given and never opened. They also tried to replicate my JBL C36-030 speakers and they gave me a set. I still have them and installed the original JBL components. Unfortunately, the 1 1/2" thick multi-layer plywood available in Japan was not as dense as what was available in the US of the time. I had to significantly internally brace the box....but they sure look nice. I also have a set of JBL 4320 speakers. Through JVC, I also obtained some high end Sansui stuff. I still have my AU-20000 and AU11000. Was thinking of using them to hook up a CD4 system. I have about a dozen unopened CD4 records they gave me plus their test/adjustment record. Unfortunately, I no longer have a Shibata stylus capable of playing the records. I'd like to find one.

Thank you for letting me tell a story that absolutely no one in my life today cares to hear - and probably you too

Cheers from near Seattle
Rich

 

[sjcorne]

I have about a dozen unopened CD4 records they gave me plus their test/adjustment record.

Great story! Out of curiosity, what are the titles? Are they Japanese or US pressings?

 

[EmeraldCity]

Well.....at the moment, I couldn't tell you. I have about 3-400 records from the 70's and they are all in boxes stored away. I'll try to dig them out over the next few days and let you know. I don't remember buying any of them so now I'm curious to know too.

 

[furui_suterioo]

I do love reading about cd-4 and quadraphonic technology in general, very interesting story. The sound on this unit cleaned up pretty good after a while, and even makes my kenwood demodulator seem just a little flat in regards to front/rear seperation, I am now looking to get a Blue Jeans LC1 or Mogami 2964 interconnect. My dollar store cables cause carrier loss in my built in kenwood demodulator when using 2ch direct mode from the 4DD10.

 

[EmeraldCity]

Since several of you seem to be familiar with setting up a CD4 system, may I ask what cartridges are recommended? I wish I had unlimited funds, but my wife doesn't seem to appreciate such expenditures as "necessary". I'd like to know of any budget recommendations. With no current price reference, I guess I'm asking if anything is available for $1-200 - probably used.

 

[winopener]

Look for the Audio Technica ones:
used or NOS, 440MLa / 440MLb
new, 540ML.

A bit pricey but these are the ones that give you no hassle on CD4 playback. It's very likely that anyone doing CD4 here on QQ have one of these.

 

[EmeraldCity]

Look for the Audio Technica ones:
used or NOS, 440MLa / 440MLb
new, 540ML.

Thank you! I’ll see if I can find one of these!

 

[Owen Smith]

I do love reading about cd-4 and quadraphonic technology in general, very interesting story. The sound on this unit cleaned up pretty good after a while, and even makes my kenwood demodulator seem just a little flat in regards to front/rear seperation, I am now looking to get a Blue Jeans LC1 or Mogami 2964 interconnect. My dollar store cables cause carrier loss in my built in kenwood demodulator when using 2ch direct mode from the 4DD10.

The 2CH direct switch on the JVC demodulators is awful, with nasty silver contacts. It degrades the incoming CD-4 signal and it degrades any passed through signal. Best advice I've seen is to solder blob across it to permanently connect it in the direction for demodulating.

 

[furui_suterioo]

when I first turned it on it had some hum but after I sprayed the button it the hum disappeared, I can tell that the faceplate on my unit has never been taken off so I don't really want to take it apart all the way, but I do want to be able to a/b the sound with my built in demodulator. I'm still able to receive the carrier even through the 2ch direct output through my dollar store cables, but there is slight breakage on strenuous sounds so I figure a high quality cable should be just enough improvement to eliminate these small breaks. The demodulator inside my kenwood is not as sensitive as the jvc, it doesn't pick up high frequency signals from non-cd4 records, unlike the jvc which seems go into 4ch mode on louder parts of non-cd4 records :/

 

[amontass]

I have 5 JVC 4DD 5s all recently fully restored. They all had capacitor problems....so now I have backups for my Lafayette 5000 and Sansui qrx 7001 because their internal CD4s do not work very well. The JVC outboards function a lot better. Never heard of a JVC ADD 10.

 

[Circular Vibes]

I have 5 JVC 4DD 5s all recently fully restored. They all had capacitor problems....so now I have backups for my Lafayette 5000 and Sansui qrx 7001 because their internal CD4s do not work very well. The JVC outboards function a lot better. Never heard of a JVC ADD 10.

When you changed put capacitors, did you have to adjust anything inside or did they work without adjustments?

 

[amontass]

No, just capacitor replacement. Work done by the owner of "Save On Sound" in Houston, a one man shop who knows quad very well and as far as I know has not ever made a mistake or did anything that did not need to be done. I have 2 fully restored Lafayette LR5000s and the fully restored Sansui QRX 7001 all done by him.

 

[gvl_guy]

I have 5 JVC 4DD 5s all recently fully restored. They all had capacitor problems....so now I have backups for my Lafayette 5000 and Sansui qrx 7001 because their internal CD4s do not work very well. The JVC outboards function a lot better. Never heard of a JVC ADD 10.

I'm in the same boat as you. Sansui QRX-7001, demodulator not great, bought a NOS JVC 4DD-5 but it was dead when I plugged it in. A local shop replaced all the capacitors and "a few relays" (sorry, I'm not that tech savvy) but the CD-4 is still not right. My cartridges are fine and my turntable and connectors are good. It's just me and CD-4 I guess.