What's the Latest DISCRETE Quad LP Added to Your Pile? CD-4, UD-4

[sjcorne]

It was a nice surprise finding a copy of Passport's Hand Made in a local shop! I can count the number of times I've found foreign quad pressings in a store on one hand.

Haven't had a chance to spin it yet, but I got a kick out of how they describe matrix quad in the album insert ("each speaker is haunted by ghosts from other channels" - LOL).

 

[fizzywiggs41]

About a week ago ...I was trolling thru the records at a local thrift store.

To my surprise there was one quad record....Virgil Fox Heavy Organ live at Carnegie .

This was originally single inventory quadradisc , but later issued in Stereo only ,so it becomes limited edition according to the Quad Incorporated Catalogue .
And there are 4 or5 others under the same circumstances, at least as per their RCA Classical section states .

Anyways for 50 cents and in very good condition, I can't complain.
Probably played only once by a Granny prior to Sunday Church.

 

[Doug G.]

I have it, too, and it's very good. Mostly ambiance in the backs but hey, that's what quad was sometimes all about.

Doug

 

[fizzywiggs41]

I have it, too, and it's very good. Mostly ambiance in the backs but hey, that's what quad was sometimes all about.

Doug

The only drawback to me picking this disc up ,is that I no longer have a demodulator .

So I'll play it thru a good synthesizer, like Involve or Fosgate's Tate synthesizer.

 

[par4ken]

Haven't had a chance to spin it yet, but I got a kick out of how they describe matrix quad in the album insert ("each speaker is haunted by ghosts from other channels" - LOL).

What they don't tell you is that instead of ghosts you get sandpaper effects with CD-4! Not to mention the rolled off high end!

 

[jupp369]

had also a lot of sandpaper till I accidental lower the tone arm for 2mm. That makes sense, because around '74 they changed the vertical angle.
Good Luck

 

[Doug G.]

I very rarely get "sandpaper" or other distortions, even with some of my very old examples. Like I have written elsewhere, playing CD-4 records is really no different from playing regular two channel records, for me.

Doug

 

[edisonbaggins]

Trying to get some kind of list together for y'all. It's overwhelming.
At least 100 titles. Lots of duplicates too, in case anyone needs or wants.

 

[Doug G.]

I thought you just had the three which are now gone.

Doug

 

[kfbkfb]

I very rarely get "sandpaper" or other distortions, even with some of my very old examples.

Please list your CD-4 playback equip (including phono cartridge alignment systems), could be helpful for those setting up a CD-4 playback system for the first time.


Kirk Bayne

 

[par4ken]

I very rarely get "sandpaper" or other distortions, even with some of my very old examples. Like I have written elsewhere, playing CD-4 records is really no different from playing regular two channel records, for me.

Doug

Yes with considerable effort it's possible to get rid of or at least reduce those sandpaper effects, but you still have the high end roll off.

As for "ghosts" with matrix, I don't hear no ghosts via the S&IC or via the QSD-1!

 

[Doug G.]

CD-4:

Cartridges: Pickering XUV-4500Q, Empire 4000 D/I, Empire 440D, Pickering 780/4DQ, Panasonic EPC-451, Panasonic EPC-450C II, Audio Technica AT912Sa, AudioTechnica AT440MLa All with genuine styli and they all work. The AT440MLa is, perhaps, not quite as good (it sometimes loses it with very complex, loud passages) but it was, after all, not designed as a CD-4 cartridge.

Turntable: Either a BIC 980 or BIC 1000. The mechanisms (tonearms, etc.) are essentially the same. Setup is by the manual except for anti-skate explained below.

Demodulators: Panasonic SE-405, Technics SH-400

Amplification: Heathkit AA-2010 quadraphonic amplifier for the upper set of original Advent speakers. Bell & Howell AAD-210 quadraphonic amplifier for the lower set of original Advent speakers. This is essentially the same as the Heathkit amplifier and, in fact, was made by Heathkit I can sub Heathkit AA-29 amplifiers if I want to. The power output amplifiers are basically the same as the quad amps.

Speakers: Four original Advent stacks driven as indicated above.

Years ago, I just adjusted anti-skate (about 15 - 20% lower than VTF) for no distortion from either channel and it has been fine since. If anything, performance has gotten better over the years It seems the more the records are played, the better they get.

I don't really notice the roll-off. I mean, the response is still up to 15kHz which is up near the upper limit of most people's hearing anyway. FM radio has the same upper limit. Personally, I can hear well above 15kHz but it just doesn't sound much different from a 20kHz system.

I also want to make it clear I am not denigrating matrix quad in any way. I don't even have a high falutin decoder, at all. No Tate or Surround Master or anything like that and I don't believe they are necessary. I just have a Sony SQD-2050 and when I play the channel identification track on the Popular Science SQ test record, all channels are where they belong. Only the left back channel is a little vague but in actual use for music sources.. it's fine. The resulting soundfield is perfectly satisfactory. 20 dB separation isn't really needed for great quad performance. 10-15 dB works fine.

Doug

 

[kfbkfb]

https://www.audioservicemanuals.com/b/bic/bic-980/60782-bic-980-owners-manual^^^
(page 14)...total cable capacitance...less than 125 pF...perfectly compatible with...CD-4


I don't know the pF range for CD-4, IIRC, 100 pF was the maximum (mentioned in some articles).


Maybe these posts should be moved to a new thread - something like "A CD-4 setup that works very well".


Kirk Bayne

 

[Doug G.]

Cable capacitance has always been a bit vague with the 100pF max. often quoted but various other numbers have been proposed/given, too, such as so many pF per foot, etc.

I use the original cables that came with the BICs and they are fine. And, contrary to almost universal belief, low capacitance cables are not necessarily thick.

Doug

 

[kfbkfb]

Any favorite cartridge(s) for "problem" CD-4s (usually means the sum/baseband signal is too loud)?


Kirk Bayne

 

[edisonbaggins]

 

[J. PUPSTER]

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Looks like you've adequately Courted and Sparked your Quad collection there Baggy

 

[DuncanS]

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Looks like you've adequately Courted and Sparked your Quad collection there Baggy

Quadded the Quad!

 

[fredblue]

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now this pic will come in handy!

..as evidence next time i'm berated by a friend or family member for having multiple versions of the same thing!

 

[fizzywiggs41]

Wow ,Mike.

That's Sixteen Channels of Joni !
Set em all up and you best any Atmos system ,