According to my knowledge the analog noise reduction CX is working well only if there are TWO analog more or less coherent audio channels, i.e. either two analog mono channels with the same content (so-called "2.0 mono"), or two analog channels with the left side and the right side of a stereo sound (so-called "2.0 stereo").

CX does NOT work well, if the two analog channels contain completely different sound (if it is an analog bilingual disc with e.g. English in one channel and Japanese in the other) and it also does NOT work well, if one analog channel contains music with vocals (= the voice of a singer) and the other analog channel contains the same music but without vocals. This configuration is used in many Karaoke Discs, where the voice of the singer is contained only in the left analog channel, and the right analog channel (and the digital channels if available) contain the pure karaoke music without singer. This type of Karaoke disc (as well as the analog bilingual discs) is labeled "MULTI-AUDIO".

I think that on analog MULTI-AUDIO discs never CX noise reduction is used !

Can anyone confirm that analog MULTI-AUDIO (on a Karaoke LD) and CX are incompatibel ?
Or does someone have a Karaoke LD with both analog MULTI-AUDIO and CX on it ??

Please note that there is also another type of MULTI-AUDIO disc, where the analog soundtracks (stereo) have different content than the digital soundtracks (also stereo). In this case the analog channels may well use the CX noise reduction. This configuration is often used in modern bilingual discs but only seldom in Karaoke discs.

My questions do not relate to this second type of MULTI-AUDIO, I am relating only to analog MULTI-AUDIO discs where there is a difference between the left and right analog channel as described above.

Different mono soundtrack and CX won't mix at all...

Either it could be a cover mistake, or a LDDb mistake

Julien

What equipment are you using???
Are you using a stand alone CX decoder.
There is a bunch of info on the forum from disclord who posted a lot regarding CX.

Karaoke being mostly later made LD releases and most late players have automatic CX cueing based what's on disc. So the player would tell you, I think.

You see me surprised You tell me what I am trying to tell you since weeks?

If you have e.g. a look at the Karaoke LD-Singles whose reference start with "COMK-" you will see that you have accepted them all with having CX on it, what is impossible because they are from the above mentioned MULTI AUDIO type what is written on the back cover! The only one COMK that has been input without CX is the one I have submitted (COMK-191) and this one is PENDING since more than a month. On March 15th I additionally sent you cover pictures (front and back of COMK-191) to prove that there is Multi-Audio written on them, but no CX. But this e-mail (as well as the next) did not get any response from you.

So please tell me why you do not accept my COMK-191 submission ...

@all:

Sorry, but somehow the text of my starting post seems not to have been clear enough to bring my message through - I did not ask about anything related to my equipment, I only wanted to know whether anybody here sees a theoretical possibility to combine analog Multi-Audio with CX ...

I see what you're saying.

Do AC-3 discs use CX? That seems like as blatant of a violation as possible of the idea that the L and R need to be similar.

Someone should dig up those Disclord posts about CX. I remember them being interesting but I forgot it all because...I don't care about CX.

Hi!

I'm not sure what we're talking about here but the info on COMK* says the analog tracks have both the vocals, then CX is OK. But back cover shows no CX so I suppose it's MONO and CX is useless.

Could you make a round of updates if you have the LDs to confirm?

For your update I was 1/ away for 2 weeks and 2/ the track list needs HTML formatting and I try to do a round of Karaoke titles once a month to optimize the process. And then the more title will require that I update the other COMK as well to be consistent and I always postpone more complicated updates to take care of the quick'n'easy ones on my spare time at work

Julien

@Julien:

Thank you for clarifying the long pending time of my "CX-free submission" and the coincidence with the missing feedback mails. Obviously I have jumped too quickly to wrong conclusions.

The COMK-* Karaoke laserdiscs in LDDb are from one contiguous series "Columbia Laser Karaoke BEST 4: Highlight" series that appeared from about 1991 till 1998 and the only difference between the early numbers versus the newer numbers is that some time between 1995 and 1998 the imprinted prize changed from 2000 Yen (including tax) to 1942 Yen (excluding tax) - so the prize was actually always the same during those years, i.e. 2000 Yen.

That it is indeed "Multi Audio" you can see on the back cover scan of COMK-191 I sent to you about 4 weeks ago, and on the back cover scans of COMK-83 and COMK-241 which are already in LDDb. However I started wondering why "Multi Audio" is nowhere written - did I miss the input field for that, or is it "automatical" - but then why does this hint not appear on screen?

Never

It's always Digital + Analog + AC3, the Mono analog being sometimes used for commentaries.

Julien

@signofzeta:

These Laserdiscs have never CX:
1. Analog-only Laserdiscs from 1978-1980. CX got introduced in 1981 and then quickly became "standard" for the analog soundtracks of Laserdiscs.
2. Analog-bilingual Laserdiscs with e.g. English in the left analog channel and Japanese in the right one, as in "V" and "V2" (NJL-11443, NJL-11576).
3. Karaoke discs with analog-MultiAudio, i.e. music without singer in the left analog, and music with singer "assistant vocal" in the right analog channel.
4. NTSC Laserdiscs with DD 5.1, because there is only one analog channel left - the left one. The right one is replaced by modulated AC-3 with 384 kbps.
5. NTSC and PAL 12 cm VSD and CDV Laserdiscs, because they don't have analog soundtracks at all.
6. PAL Laserdiscs with digital soundtrack (PCM or in rare cases DTS), released 1986 or later: because they have no analog soundtracks
7. HDVS Videodiscs (these are not really "Laserdiscs", but look like them): they have only 4 digital soundtracks and no analog ones

With these Laserdiscs you have a (good) chance they are CX-encoded:
1. Laserdiscs with analog stereo soundtracks: if NTSC then mostly from the years 1981-2007, if PAL then mostly from the years 1982-1986.
2. Analog/digital-bilingual Laserdiscs with the original language in the digital soundtracks, and another language in the analog ones.
3. Karaoke discs with analog/digital-Multiaudio, i.e. music without singer in the digital soundtracks, and music with singer (assistant vocal) in the analog ones.
4. NTSC Laserdiscs with DTS 5.1 sound, because they have both analog channels left for stereo or Dolby Surround sound.

About MUSE Hi-Vision Laserdiscs I am not sure: some of them have analog soundtracks and these could technically use CX, but do they really?
Does somebody know?

CX became the standard for stereo discs. Many studios didn't bother with doing CX noise reduction on mono discs until MUCH later. There are analog only mono titles as late as 1989 that do not have CX. The first round of CX encoded players (Pioneer LD-660, LD-1100 & PR-8210 and the Magnavox/Sylvania equivalents) had manual CX circuits. Around 1985 Pioneer developed 'CX auto-switching,' inwhich the disc would automatically enabled CX on the player - and lock it on (or off).



A healthy chunk of the feature films issued in DTS on LD have audio commentary tracks ("Dark City" has two) and "Rush Hour" has a commentary track and isolated score. So no CX on these.



MUSE discs don't have the FM channels, so No CX is encoded on those discs.

There are a handful of multi-audio titles (mostly pressed by PDO-UK after PAL dropped analog tracks) that force CX on by mistake.

Interesting I didn't know there was outboard add on CX decoders. I just can't get the CX to switch on, with Pioneer DVL909 with other players I have thou not presently working CLD1750 I could easily switch the CX on for analouge. I may see if any cheap going outboard ones are available?

http://laservideodisc.tripod.com/LD_Players/id4.html

On current discs, you'll never see that CX is switched on. If the disc is encoded with auto CX switching, the player will lock either ON or OFF, based on the disc. To toggle, you bounce through the audio output selector, Digital Stereo, Digital Left, Digital Right, Analog Stereo, Analog Left, Analog Right. If you have a Manual CX disc, the Digital options will be replaced with, Analog Stereo CX, Analog Left CX, Analog Right CX. I've never seen a Digital Audio disc with manual CX.

I find it somewhat of a drag that you can't see that CX is on. The DVL-919 does the same thing.

@laserbite34:

Nobody protested loudly when Pioneer started to cut out the CX indicator lamp. After a while it was gone.
Happens again and again - long time ago the counters on cassette recorders were quietly dropped in a similar way.

But the CX function is there and works perfectly - even if not indicated. All NTSC discs with analog and digital soundtracks use CX auto-switching on the analog tracks as far as I know - so there is nothing to see any more about CX (and on Karaoke discs with analog multi-audio there is no CX at all).