Involve CD4....Is there any life in it????

[The Quadfather]

I noticed that Lou didn't include the numbers for the chips. Perhaps a move to prevent design copy infringement? Now it's important info that is missing. However, some of those chips were to be custom programmed from what I recall.

I will wait and see on the new demod. If the number of orders start approaching what is needed, then I will decide.

The Quadfather

 

[chucky3042]

Hi All

Just a quick update, we have now 36 pioneering types, this equates to a per unit price of $628. This is like plucking teeth sideways, slow and painful.

Oh well at least its getting to be a possibility!

Regards

Chucky

 

[chucky3042]

Hi All

Just a quick update, we have now 36 pioneering types, this equates to a per unit price of $628. This is like plucking teeth sideways, slow and painful.

Oh well at least its getting to be a possibility!

Regards

Chucky

 

[John Svensson]

Chucky, I would probably be a "Yeah", but I can't hard and fast commit until my.....humpf, clear throat, legal entanglements are resolved..... John

 

[krkier]

I noticed that Lou didn't include the numbers for the chips. Perhaps a move to prevent design copy infringement? Now it's important info that is missing. However, some of those chips were to be custom programmed from what I recall.

This is what I found out about Lou Dorren's design way back when he introduced his schematics:

Look for:

ADG 5209 (Analog devices)
MC14060 (ON Semiconductors, or equivalent)
NE571 (Philips, now obsolete)
UTC571 (Youwang Electronics, same as above, possible replacement?)
XR2211A (Exar)

They should match the relevant silicon in the schematics.

The only thing I couldn't figure out was his ANRS, IIRC.

-Kristian

 

[DuncanS]

This is what I found out about Lou Dorren's design way back when he introduced his schematics:

Look for:

ADG 5209 (Analog devices)
MC14060 (ON Semiconductors, or equivalent)
NE571 (Philips, now obsolete)
UTC571 (Youwang Electronics, same as above, possible replacement?)
XR2211A (Exar)

They should match the relevant silicon in the schematics.

The only thing I couldn't figure out was his ANRS, IIRC.

-Kristian

I've found that a lot of the Taiwanese companies only supply in 1000s or 10000s, which might be an issue. The SSM2166 (from Analog Devices) is probably the nearest modern device I could find to the NE571, so the original circuit would need to be modified. http://www.analog.com/en/products/audio-video/audio-amplifiers/ssm2166.html#product-overview A lot of SSM devices are used in mixing desks. (NB: SSM was Solid State Music (before being bought by Analog Devices), many years ago I used a lot of their chips in a geophysics instrument I designed for my PhD!).

 

[chucky3042]

Hi All

Whilst I would love to do a pure hardware version (I like it) the only way we could consider doing it and achieve a low cost would be to adapt the software on the existing SM circuitry....looked at it and it is possible.

Regards

Chucky

 

[krkier]

Yes we understand, Chucky. A software based demodulating and expansion with DSP will be more "modern", and also more versatile when using other DSPs in the future.

Posting my observations about Lou's cirquit was only for "sentimental reasons"....

-Kristian (who loves backwards engineering from time to time)

 

[Quadro-Action]

I would also accept for a new CD-4 Demodulator the both versions - one based on Lous developments and also the Involve DSP construct. Only important is, that we can get a very well channel separation of 35 dB (lous announcement) or more) and a modern hifi sound from new circuits or DSP's.

Dietrich

 

[chucky3042]

Hi Quadro Action

I see no issues with getting 35 db separation - given the accuracy of dsp. My only amusement is that on our tests with audiences of "test monkeys" we found that no one could discern any improvement beyond 12 db of separation with musical content. I know its not relevant to the discussion but I really find it funny that after all the separation numbers war no one actually sat down and did some double blind studies of how much separation is really required. We were very surprised with the result but it turns out 12 db is a "magic" number in human perception - see Haas.

Just being controversial.....I am allowed to after peddling 30 miles into a gale force wind

Regards

Chucky

 

[fredblue]

"Only" 12 dB of separation!? Wow! :yikes

How many dBs separation are we getting out of the SQ vinyl edition of the Surround Master, Chucky?

 

[bmoura]

Hi Quadro Action

I see no issues with getting 35 db separation - given the accuracy of dsp. My only amusement is that on our tests with audiences of "test monkeys" we found that no one could discern any improvement beyond 12 db of separation with musical content. I know its not relevant to the discussion but I really find it funny that after all the separation numbers war no one actually sat down and did some double blind studies of how much separation is really required. We were very surprised with the result but it turns out 12 db is a "magic" number in human perception - see Haas.

Just being controversial.....I am allowed to after peddling 30 miles into a gale force wind

Regards

Chucky

Actually that's not too far off some of the early Quad Tests in the 1970's that found that after 20 dB of separation, most listeners couldn't tell the difference if more separation was available on a recording + playback system.

 

[chucky3042]

Hi Fredblue

I have attached here a bunch of tests we conducted on QS and SQ, please note that on some the reference levels were not normalised to zero. You will note that the SQ tests with properly encoded script SQ produced really good results with say 20 - 35 db separation everywhere but with vinyl SQ decoded on our original SQ software the results were less for front to rear decode of between say 10 - 15db (bit hard to summarise -put your thinking caps on and look at the tables and allow for the lack of normalisation).

On Tabs test track with the trumpets it really showed up this problem. When we updated to the Vinyl SQ edition it was clear that we were getting better than 20 db separation in all directions- frankly we have not tabulated our test results yet but its all a bit of a pissing contest above 20 db (even 12 db) what matters is the sound and lack of artifacts.

Please note that one of the big differences apart from our Involve decode algorithm between the Tate and the SQ SM is we are tri band. We claim you can really hear this....I can.

Hope this helps

Regards

Chucky

"Only" 12 dB of separation!? Wow! :yikes

How many dBs separation are we getting out of the SQ vinyl edition of the Surround Master, Chucky?

 

[chucky3042]

Just a reminder

The SQ vinyl results above ARE FOR THE ORIGINAL SQ DECODER not the new vinyl edition SQ SM.

 

[chucky3042]

Ooops

I really should have posted this stuff on the SQ thread.

Ooops

 

[fredblue]

Hi Fredblue

I have attached here a bunch of tests we conducted on QS and SQ, please note that on some the reference levels were not normalised to zero. You will note that the SQ tests with properly encoded script SQ produced really good results with say 20 - 35 db separation everywhere but with vinyl SQ decoded on our original SQ software the results were less for front to rear decode of between say 10 - 15db (bit hard to summarise -put your thinking caps on and look at the tables and allow for the lack of normalisation).

On Tabs test track with the trumpets it really showed up this problem. When we updated to the Vinyl SQ edition it was clear that we were getting better than 20 db separation in all directions- frankly we have not tabulated our test results yet but its all a bit of a pissing contest above 20 db (even 12 db) what matters is the sound and lack of artifacts.

Please note that one of the big differences apart from our Involve decode algorithm between the Tate and the SQ SM is we are tri band. We claim you can really hear this....I can.

Hope this helps

Regards

Chucky

Thank you so much Chucky! Such great in depth info!

'Tab's Trumpets' are the track "Open Up Wide" by the group Chase, which is one of the tracks I've tested so far (from a Sony SQ Test/Demonstration LP that's a lot of fun) through the SQ Vinyl Surround Master.. and decoded by your updated SQ vinyl Involve unit it is nothing short stunning, with the round the room pan executed with aplomb! (That's even better than with a lemon, or with a banana!) :banana:

 

[fredblue]

Ooops

I really should have posted this stuff on the SQ thread.

Ooops

My fault for bringing up the SQ Involve separation thing!

 

[JR Hearne]

Please count me in!

J.

 

[bigbillquad]

Hi. All
We can do better than this geeeeeeeeeeeeeeeee wiiiiiis :scream this is a once in a life time event, if it happens but we need more numbers, my finance is not great but I am willing to pay up to 7 to $800.00 for this new CD-4 Demod.
Bill..

p.s. CHUCKY if the numbers get to a point where you think it might happen you may need to open a link some where on your web site to register the people.

 

[bigbillquad]

Hi. Quadro-Action

I have now written to the japanese HiFi-Forum [email protected] that they may inform their members,that we have now the possibility to get a new CD-4 Demodulator and the japanese fans can inform or may do an order in the QQforum. We will see,if there is any response or echo. In our german HiFi-Forum are named some asia hifi-forums.

Dietrich

Has there been any reply from the Japanese HiFi-forum. we really need the numbers.you would thinck that the Japanese would jump on board CD-4 was pretty big in Japan at the peak of Quad..
Thanks Bill....