From: wlrc@uhura.neoucom.edu (William R. Cruce)
Subject: Re: Selecting an LD Player
Keywords: Laser Disk, fiber optic output
Organization: Northeastern Ohio Universities College of Medicine
Date: Wed, 30 Dec 1992 07:30:38 GMT

In article <1992Dec29.171405.1480@lsican.uucp> michael@Canada.lsil.com writes:
>
>[...]Error correcting comes to mind here).  If the only "audible" differences
>between players comes from the DAC portion (plus power supplies, etc), then with
>an outboard DAC, all CD/LD players should sound identical.  Is this a true
>statement?

No.  It is not true.  Theta makes a "CD Transport" which is a modified
Philips LD player [major mod is to correct for 'jitter'in the digital
output, according to their literature].  Fed into their ~$1000 outboard
D/A (I forget the model #) it sounds better than a Pioneer CLD-3070
LD player fed into same.  Unfortunately the Philips video is no match
for the Pioneer player.  So you can get good Video with a Pioneer LD
player and improve the audio with an outboard box.  However for the
price of the outboard box, my Mod-Squad modified old Magnavox (Philips)
CDB-650 CD player was better.  Of course the combination of Theta
player and Theta D/A box was superb (almost as good as a good analog
vinyl system) but its cost was +$2500. 

This is all 'cutting edge' stuff.  I do not personally know of any
combination of components which will give both the best sound and the
best video.  For most situations the differences in video between differ-
ent LD players will be more obvious than the differences in audio.  I
can personaly recommend the Pioneer CLD980 (cheap), CLD3070 (moderate).
and CLD-95 (expensive) for video.  The first two are not current models
and may no longer be available.

It would be interesting to determine the best possible combination of
boxes for both video and audio but I don't know of anyone who has
rigorously tested for that. 

>What is the resolution of the LD medium?  I've seen Pioneer LD players with 425 lines
>of resolution, do any other players do better, or is this number a function of
>the medium itself?  The best S/N ratio I've seen is 50 dB, is this also a function
>of the medium?

I don't think the published specs have any basis in reality.  The Pioneer
elite LD players, CLD-95 and LD-S2 will barely meet the 425 lines spec.
The CLD-980 and CLD-3070 are more like 380 lines ( and I suspect, but 
have not tested, that other players are in this 380 line range).  The
S/N ratio as published is probably meaningless.  The CLD-95 has the
lowest color noise (streaking in red) of any player I have seen; the
LD-S2 is a close second.  Several other reviewers think the 
CLD-95 is the best player currently available (for video).  The other
Pioneer players are not too far below this.  Unfortunately many of the
mid-priced Pioneer players have various problems;  you need a guide
book to steer you through them -others on the net may provide that
info.

>Do any LD players perform picture enhancement, colour blooming removal, or any
>other DSP type functions on the video image?

Not really.  The LD-S2 performs some functions in the digital realm,
but the result is similar-to-poorer than that of the CLD-95 which does
not process its video in the digital domain. 

>I've looked briefly at the Pioneer 701, can anyone make any comments on this
>unit, or recommend other above-average LD players?

I have no experience with the 701, perhaps others can comment.


-- 
	The answer is never simple and is always changing.
    William L.R. (Bill) Cruce       INTERNET: wlrc@uhura.neoucom.edu 
Neurobiology Dept, NE Ohio U Coll of Med, POB 95, Rootstown, OH 44272