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

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Hi!

Still alive and kicking. The issue was not us but the company we shared a building with went into liquidation and we got caught in the mess and actually got locked out of our own factory for 3 weeks (Liquidators are such ignorant pricks).

Happy days are here again we have relocated only about 2 klm away to:

No 2 Shearson Crescent Mentone, Melbourne, Victoria, Australia 3194
Phone me direct on +61438698325

Still working up to the CD4 unit, its just a manpower issue.

Regards

Chucky

18/09/2016 last post and it seems the company has had big issues to hurdle and big changes to get past too

I have an address as
Involve Audio, Australia
33 Malcolm Road
Braeside, Victoria 3195
Ph: +61 3 8581 7638

without doing anything more, I shall ask

so, is the company still active?
has the cd4 addition to the surround master been completed after the last 4 months?
 
Good to hear, Chucky.
Hope you were able to get all your property.

BTW, a $500 aud for the Surround Master with the outputs and including SQ and CD4 is indeed a bargain.

I shall keep an eye on your site http://involveaudio.com over the next cupla months/years for an update.
No double a good pickup of the 30khz carrier will be necessary meaning use of a shibata and continuation of a quality signal into the decoder circuit. The software required would be, as you say, a manpower issue as well as a brainpower issue (which, I think, would border on electrical engineering genius). But you seem to already have SQ out. I cannot imagine a 2 channel output from a Yamaha (or any other) into the 2 channel input of the SM would maintain the information and allow the 30khz signal to be decoded. The required front/rear separation would not be easy to get without that 30khz signal and i cannot see the Yammy outputting it. Though i do see a 4 channel output on your SM but no specs on your description.
BTW, i'm in Bris so its amazing to see audio system developed and manf in aus.
 
BTW, a $500 aud for the Surround Master with the outputs and including SQ and CD4 is indeed a bargain.

I shall keep an eye on your site http://involveaudio.com over the next cupla months/years for an update.
No double a good pickup of the 30khz carrier will be necessary meaning use of a shibata and continuation of a quality signal into the decoder circuit. The software required would be, as you say, a manpower issue as well as a brainpower issue (which, I think, would border on electrical engineering genius). But you seem to already have SQ out. I cannot imagine a 2 channel output from a Yamaha (or any other) into the 2 channel input of the SM would maintain the information and allow the 30khz signal to be decoded. The required front/rear separation would not be easy to get without that 30khz signal and i cannot see the Yammy outputting it. Though i do see a 4 channel output on your SM but no specs on your description.
BTW, i'm in Bris so its amazing to see audio system developed and manf in aus.

Not really my place to speak for Chucky but from everything that he's told us so far, I don't think the CD4 decoder will be incorporated into the Involve/SQ SM (and certainly not for $500). I also don't imagine that the CD4 unit will do anything other than take the cartridge output directly.
 
Not much of a market if limited to just those buyers who are needing to change their clapped out demodulator for a new one and any system needs the 30khz capture. But then, no use to any new users either who dont have the means of getting that 30khz tone cleanly.
Cannot see much potential for any good sales given the new world of mp3/flac/5.2/7.1/ wifi /bluetooth and so on. Does anyone want another box or is the aim to integrate. Which then means price becomes paramount. CD4 has traditionally been included with QS and SQ in one box with one power supply. Those demand days are gone now and existing cd4 systems have well passed their use by dates. The business/investment plan would be tricky to set and would not justify development and tooling a new product but i could see it appended to an existing one..
 
Hi All

Soundfield is right. This project is not intended for the general market in anyway as CD4 is a dead duck. More it will be as a favour to this great forum for all the help you guys have given us. The issue was would we get enough buyers to cover the R+ D effort. So far I think we have the numbers to make a CD 4 dedicated demodulator for around the $500 mark.

We are still super busy and Overture (Dave the Bitch) has a priority list that goes something like this:

1 Redevelop studio encoder...............................................Completed awaiting manufacture
2 redevelop Y4 surround electrostatic system.......................Completed in manufacture
3 Design Involve evaluation modules for industry evaluation....Completed, manufactured being packed for sale (news soon about this)
4 Design new Y2 two channel electrostatic surround system....90% completed
5 Design Involve pre amplifier.............................................30% completed (I really want one myself)
6 The CD4 demodulator.....................................................5% completed some initial plans

Plus our mechanical monkeys will shortly be releasing the Involve decoder in a Metal case!!!!!!!!!!!!!!!!!!!!!!!!!!

In addition we are designing some exciting flat packed assemble yourself electrostatic kits for another company, also a electrostatic soundbar (I hate the bastards but this one has a real trick)

And while we are at it we are really busy in our solar storage company www.catchenergy.com the website is a pile of crap!

Also we have developed for our other sister company IC12 the world first lensing system that can focus LED arrays
https://www.youtube.com/watch?v=tumTg4xnXog


Apart from that its quiet - too quiet

Regards

Chucky
 
This project is not intended for the general market in anyway as CD4 is a dead duck.

You are a master of understatement Chucky - I think CD4 was as dead as a Dodo thirty years ago!

our mechanical monkeys will shortly be releasing the Involve decoder in a Metal case!!!!!!!!!!!!!!!!!!!!!!!!!!

Great news!!

Cheers,
Soundfield.
 
So I am happy with my JVC 1000 Demodulator with some restored or renewed technicak details. From CD-4 records the Hugo Montengero for example sounds astonishingly with more dynamic and musically and with also big channel separation as the reissued SA-CD's. So I can take it well, when a new CD-4 Demodulator may be further on a dream.

Dietrich
 
Hi!

Still alive and kicking. The issue was not us but the company we shared a building with went into liquidation and we got caught in the mess and actually got locked out of our own factory for 3 weeks (Liquidators are such ignorant pricks).

Happy days are here again we have relocated only about 2 klm away to:

No 2 Shearson Crescent Mentone, Melbourne, Victoria, Australia 3194
Phone me direct on +61438698325

Still working up to the CD4 unit, its just a manpower issue.

Regards

Chucky
What is your phone Number
If I ring from Croydon
I don,t seem to be able to ring

Ron
 
Hi Ron

Since relocating we have ditched our standard phone lines and we are all using mobile phones!

My mobile is

international +61438 698 325

local Australian 0438 698 325

Be good to catch up again and I demand that you visit our new factory as we have lots of new stuff to show!

Regards

Chucky


What is your phone Number
If I ring from Croydon
I don,t seem to be able to ring

Ron
 
Hi Circular Vibes and all

I would be looking at a deposit of 30% up front before we start design, and yes I would accept the rest in say 2 payments, I know how tight money can be!

We have had one "buyer" drop out so by my best tally we are up to 19 test rabbits. Also I have had a closer look at R+D costs and its more like $15,000, putting those numbers in and allowing for all parts/ labour etc we are now down to $1,139.........if we can round up the other 10 possible buyers it gets down to $850.

So we are possibly getting close to a reasonable target price. We just need to "mine" more starters.

ALSO it is unclear from the Lou's circuit diagram what some of the chips are particularly FDB 5/4, U34, U36, U31, U17, U16, U10, U8. Does anyone have the BOM details on these.....the less we need to "think" the less it will cost!!!!

Looking promising

Chucky

Hi there
How is this project running?
Regarding Lou Dorren's LP and BP filters not much was written, except he mentioned fine-tuning, I think I remember. He published one picture of his main PCB with six daughter-boards. Four small presumably LP-filters, and tow larger, presumably BP-filters.
I downloaded Linear Technology's FilterCAD SW, and fiddled just a little with it and got a response quite similar to one BP-response published by Lou Dorren:
response.PNG
The response is with a Switched Capacitor filter LT1068-25 and it is pretty similar to Lou Dorren's. The clock frequency is 825kHz, with all possibilities for clock bleed through.
Filter CAD also gives the choice of "Active RC" like the LT1562
The LP-filter may also be made similar.
The CD-4 system requires a 3kHz deadband between 15khz and 18kHz. Lou Dorren set his LP-filters to 15.667kHz.
The LP-filter shown in the "High Performance 2007 CD-4 Demodulator" Installment II is 60dB down at 18kHz. He stated he used an 8-pole filter. (I got a similar response in FilterCAD.)
Installment III shows the BP-filter down 40dB in the stopband.

I intend to look into this in more detail, and for the time being I believe more in the "Active RC" concept of LT.
However, we do not know if Lou Dorren used Linear Technology devices at all.

Information about the CD-4 specification is appreciated, in the mean time I'll have a look into the AES library.

Regds
Rolv-Karsten

LP-filer = Low Pass filter
BP-filter = Band Pass filter
 
Sadly I've no particular interest in CD4 now, I wish I'd build a demodulator as a student and got all the LPs back in the mid-late-70s!

I'd go with the Active RC approach as well, possibly using Gyrator circuits to simulate inductors to produce the required high order filters, which I used quite successfully in a seismic system. My Filter books of choice are Anatol I. Zverev, "Handbook Of Filter Synthesis", Wiley Inter-Science, ISBN 0-471-74942-7, and Arthur B. Williams & Fred J. Taylor "Electronic Filter Design Handbook", McGraw Hill, ISBN 0-07-070434-1.

I've used switched capacitor filters in instrumentation, and they're OK for that, but they tend to be 'noisy' due in part to the switch charge injection, so tend to give poor performance at low signal levels. Which isn't ideal for audio.

Hi there
How is this project running?
Regarding Lou Dorren's LP and BP filters not much was written, except he mentioned fine-tuning, I think I remember. He published one picture of his main PCB with six daughter-boards. Four small presumably LP-filters, and tow larger, presumably BP-filters.
I downloaded Linear Technology's FilterCAD SW, and fiddled just a little with it and got a response quite similar to one BP-response published by Lou Dorren:
View attachment 28629
The response is with a Switched Capacitor filter LT1068-25 and it is pretty similar to Lou Dorren's. The clock frequency is 825kHz, with all possibilities for clock bleed through.
Filter CAD also gives the choice of "Active RC" like the LT1562
The LP-filter may also be made similar.
The CD-4 system requires a 3kHz deadband between 15khz and 18kHz. Lou Dorren set his LP-filters to 15.667kHz.
The LP-filter shown in the "High Performance 2007 CD-4 Demodulator" Installment II is 60dB down at 18kHz. He stated he used an 8-pole filter. (I got a similar response in FilterCAD.)
Installment III shows the BP-filter down 40dB in the stopband.

I intend to look into this in more detail, and for the time being I believe more in the "Active RC" concept of LT.
However, we do not know if Lou Dorren used Linear Technology devices at all.

Information about the CD-4 specification is appreciated, in the mean time I'll have a look into the AES library.

Regds
Rolv-Karsten

LP-filer = Low Pass filter
BP-filter = Band Pass filter
 
Sadly I've no particular interest in CD4 now, I wish I'd build a demodulator as a student and got all the LPs back in the mid-late-70s!

I'd go with the Active RC approach as well, possibly using Gyrator circuits to simulate inductors to produce the required high order filters, which I used quite successfully in a seismic system. My Filter books of choice are Anatol I. Zverev, "Handbook Of Filter Synthesis", Wiley Inter-Science, ISBN 0-471-74942-7, and Arthur B. Williams & Fred J. Taylor "Electronic Filter Design Handbook", McGraw Hill, ISBN 0-07-070434-1.

I've used switched capacitor filters in instrumentation, and they're OK for that, but they tend to be 'noisy' due in part to the switch charge injection, so tend to give poor performance at low signal levels. Which isn't ideal for audio.

For me this will be a hobby project. When I have time. I agree with your thoughts switched-cap vs Active RC.
 
Hi All

I think all we really need is a list of those who are in. I was keeping track a while ago and based on a price of around USD$500 we needed over 100 "starters", I think we were there.

Given we are still around 6 months of tackling this one , I accept some sort of intention to "go" list.

Regards

Chucky
 
I too am interested, still using my Surround Master daily.
 
Hi All

I think all we really need is a list of those who are in. I was keeping track a while ago and based on a price of around USD$500 we needed over 100 "starters", I think we were there.

Given we are still around 6 months of tackling this one , I accept some sort of intention to "go" list.

Regards

Chucky

Hi. chucky

Yes a new list would be in order I was in the last list.
So you can put me "DEFFINITELY" down for one chucky...........:banana:............

So Come every body we need at least 100 of you..." CD-4 FANATICS ".........
So put your name to the new list and spread the word.....
 
Last edited:
Workman down for one, granted it is a functioning demodulator with whatever forgiveness for the 40 y/o media that it will be expected to lock into is taken into account. Nothing fancy, just a CD-4 demod only, not crammed with SQ tor QS decoders on top, or grouped buy with a cart/shibat stylus. The people who want a 21st century CD-4 demodulator have all of the other covered. Best of luck, Chucky and David. I'll start saving my pennies.

Sent from my SM-G920P using Tapatalk
 
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