Lou Dorren: A new CD-4 Demodulator!!! [ARCHIVE]

[jefe1]

Hats off to both Quad Linda and Disclord! Your posts are fascinating and I avidly read every one.....don't worry, I haven't built any shrines yet. Your knowlege bases are complemetary to each other and there is overlap. Perhaps both of you should collaborate and write a book about quad and surround....

 

[surroundme33]

I have to add a correction to what I wrote about the 7-inch CD-4 alignment discs- I was wrong about the "#2" on the inner wax of the corrected JVC CD-4 alignment disc. The incorrect disc was 4DE-202 and the right side channel separation alignment is recorded incorrectly on it. The corrected JVC CD-4 alignment disc is 4DE-205 and is meant to be played at 45rpm, which apparently wasn't stated clearly on the disc label.

I hadn't had enough coffee, my eyes were blurry and I misread what they wrote about the corrected disc. Sorry about that.

Thank You Disclord for clearing this up. I use this record religiously to set-up my CD-4 demodulators. I've yet to find the special one made for the Technics SH-400 which has that CCC adjustment on it.

 

[surroundme33]

Yes, that's not really a mix. As a musician and multi-channel geek, I like it "mixed" that way, especially discrete Quad rock/pop music. It becomes easier to focus on a particular musician in the mix, by turning that one channel up. Even at equal levels, it becomes easier to hear what each player is doing with this kind of mix.
So, it's not a technically adept mix, or more accurately, no mix at all.

Surround me, I've seen that avatar somewhere... I might be wrong. Getting punchy from looking at my SH-3433 scope.

Linda

LOL! Actually, I made it myself. I used some screen snap shots from someones youtube video of their SH-3433 scope (a machine I wish I owned). I believe the audio they were playing was the "best of Doors"..

 

[surroundme33]

SQ: >snip< you would swear you're listening to a Q4 or Q8 source. One that comes to mind is The soundtrack to Shaft. Lovely fidelity and very interesting quad effects using random 'ping-pong' effects from speaker to speaker.

This got my attention - I have had SHAFT SQ for some time, three copies no less. Always the same terrible glitches about a minute into side 3 'Do Your Thing'.. so have you got a clean copy??

I have had the opportunity to compare the Doobie's Q4 'Stampede' with a great CD-4 rip of the same and the tape source has a lot better separation - but is clearly the same 'mix'. Hm... I don't have my own CD-4 set-up so I can't test anything else...
SQ: I think that the seperation issue with SQ is far more complex than just a dB count because you are dealing with the 'way' that the sound is decoded and presented, not just the levels. Remembering that SQ works by exploiting the properties of phase differential and as such is very sensitive to just how it is decoded. There doesn't seem to be a 'absolute right way' to do it in software... As Oxford Dickie has mentioned elsewhere (though I can't remember where) SQ decoding in software is better when it doesn't concentrate so much on actual seperation, more on getting the channel balance and phase issues correct in order to get a more realistic sense of direction from all elements of the the mix. I'm only guessing but it seems to me that this requires less seperation than is technically possible with SQ. If you hear some of the stuff O.D.'s been working on with his 'final version' scripts, they are truly exceptional in terms of believability but a quick check will tell you that it's hardly the best separation possible... so perhaps seperation isn't everything after all.
Speaking of O.D., I do hope he releases the script publicly sometime before we all die... it does sound rather good.

Yep, i have an excellent clean copy of "Shaft".. PM me for info. I use the SQ scripts designed here that utilize some free plug ins that minimize the use of 'center channel extraction filter' which makes most audio sound like someone used a studio underwater. Would be curious to hear or read info on this 'O.D.' script you speak of.

 

[Quad Linda]

Disclord, you had asked about Utah. While researching Olson Electronics on-line, I stumbled upon a post on Utah. Imagine my surprise, when I went to double check the model # of my Utah's and found they were, in fact, Electro-Voice EV-4's! Cosmetically, they look nearly identical. I bought them at an estate sale in Barrington, purchase with a pile of gear, including Utah WD-90's. I thought I had kept the Utah's, but I kept the EV-4's. They're higher quality. Perhaps I own too much stuff? Chalk it off to me being a ditzy woman!

Utah history at: http://dldebertin.com/speakers/utah.htm
You Tube video on refurbishing Utah WD-90's: Part 1: http://www.youtube.com/watch?v=LlMCFoIkrDk Part 2: http://www.youtube.com/watch?v=DI5GwXv7Cvw&feature=related He's right, WD-90's were very nice speakers for cheap! We sold tons. For do it yourself'ers, I STRONGLY recommend you buy the WD-90's for the cabinets and replace the drivers. The cabinets are made very well.

Sadly, I couldn't locate on-line photos of Electro-Voice EV-4. Their woofers have a much more beefy magnet structures than the Utahs. Both are 12" 3-ways. A great compliment for the hunking Philips 477's I'm using for the fronts. BTW: I massively reworked the 477's with new 12" woofs, mids, tweets and crossovers a few years ago. I rarely do mods or repairs to anything anymore. Philips 477 pix: http://s228.photobucket.com/albums/ee307/orionkc/Philips 477 Speakers/

Sadly, I found woefully little on line regarding Olson Electronics. My post on that thread was recreated mostly from memory. The Olson thread is called "Trying to Remember?" https://www.quadraphonicquad.com/forums/showthread.php?14967-Trying-to-remember&p=133471#post133471

WE NOW RETURN YOU TO THE WORLD OF CD-4 DEMOGITATORS.

Linda

Regarding Utah speakers, they're not high end. I believe they're out of business. They were a good, cheap speaker. Excellent value. I recall a retail price of $100 each in '73-'74 for mine. They are 12" 3-ways which I bought as part of an estate sale. I quickly sold everything else from that acquisition. Since I made a profit on the rest, the Utah's were essentially free. They are paired with two Philips 3-way 12". The Philips were my main speakers until the new millenium. They were part of a Philips tuner/preamp/500 W power amp system I won in '79. Audiophiles laughed at it, but their jaws dropped when they heard it. No more laughter.

The Utahs were being driven by my Denon AVR-3801, but now are connected to my Onkyo TXSR504 on my third system. They're rears and Philips are the fronts. There is a phantom center and no sub on that system. It's still ballsy. That system cost me $35, which was the price of the Onkyo. Everything else was either won in sales contest or a gift. Best $35 I ever spent. I'll put this system against anything new under $1500. Though it may lack a bit of accuracy, it more than makes up for it in guts.

Linda,
who needs to stop yentying and let QQ get back to discussing CD-4 demogitators

 

[Disclord]

Thank You Disclord for clearing this up. I use this record religiously to set-up my CD-4 demodulators. I've yet to find the special one made for the Technics SH-400 which has that CCC adjustment on it.

I have that 7-inch setup disc, I just wish there was a way for me to digitize it so you could use it.

 

[Disclord]

Disclord, you had asked about Utah. While researching Olson Electronics on-line, I stumbled upon a post on Utah. Imagine my surprise, when I went to double check the model # of my Utah's and found they were, in fact, Electro-Voice EV-4's! Cosmetically, they look nearly identical. I bought them at an estate sale in Barrington, purchase with a pile of gear, including Utah WD-90's. I thought I had kept the Utah's, but I kept the EV-4's. They're higher quality. Perhaps I own too much stuff? Chalk it off to me being a ditzy woman!

Utah history at: http://dldebertin.com/speakers/utah.htm
You Tube video on refurbishing Utah WD-90's: Part 1: http://www.youtube.com/watch?v=LlMCFoIkrDk Part 2: http://www.youtube.com/watch?v=DI5GwXv7Cvw&feature=related He's right, WD-90's were very nice speakers for cheap! We sold tons. For do it yourself'ers, I STRONGLY recommend you buy the WD-90's for the cabinets and replace the drivers. The cabinets are made very well.

Sadly, I couldn't locate on-line photos of Electro-Voice EV-4. Their woofers have a much more beefy magnet structures than the Utahs. Both are 12" 3-ways. A great compliment for the hunking Philips 477's I'm using for the fronts. BTW: I massively reworked the 477's with new 12" woofs, mids, tweets and crossovers a few years ago. I rarely do mods or repairs to anything anymore. Philips 477 pix: http://s228.photobucket.com/albums/ee307/orionkc/Philips 477 Speakers/

Sadly, I found woefully little on line regarding Olson Electronics. My post on that thread was recreated mostly from memory. The Olson thread is called "Trying to Remember?" https://www.quadraphonicquad.com/forums/showthread.php?14967-Trying-to-remember&p=133471#post133471

WE NOW RETURN YOU TO THE WORLD OF CD-4 DEMOGITATORS.

Linda

Thanks for the additional info - I have the same problem of too many electronics. It's interesting that the model # of the EV speakers is the same as the name of their two quadraphonic matrix systems. Any relation I wonder? Like were the EV-4 speakers their 'recommended' speakers for setting up an EV-4 based quad system?

 

[Quad Linda]

I don't recall them EVer recommending EV-4 speakers for EV4. I believe that EV-4 speakers predated EV4. They made some great products, but weren't wizards at marketing.

Linda

Thanks for the additional info - I have the same problem of too many electronics. It's interesting that the model # of the EV speakers is the same as the name of their two quadraphonic matrix systems. Any relation I wonder? Like were the EV-4 speakers their 'recommended' speakers for setting up an EV-4 based quad system?

 

[The Quadfather]

This is all interesting about the NAZIs and their tonbandgerat, but what about the demodulator? When will it materialize?

The Quadfather

 

[quadjoe]

I too am anxious to news about the new demodulator. It has been a long time coming, and we're all very excited about it. So much so, that it would be great if the comments on this particular thread would be limited to discussion of it. Every time I get a notification that there is a post on this thread, I keep thinking that it is about the new demodulator, only to be disappointed when it is about almost everything else. Oh well, that's just my point of view.

 

[Malcolm2010]

Jon,

when you have the new demodulator for testing, what test regime will you have?. Not knowing your setup, I have to make certain assumptions. One is that you would be using the new demodulator with the supplied cartridge and your existing set up with its own.

What equipment will you compare the new demodulator with and what test lps will you use, it has to be high end as Lou said the new demodulator will be the best ever. I suggest that recordings be made at 96K 24 bit (unprocessed of course) for members to compare first hand and evaluate any differences.

If anyone else has suggestions, please make them, it will be an ideal opportunity for John to do some serious testing before true production starts and iron out any possible wrinkles in the design.

Malcolm

 

[Malcolm2010]

Jon,

when you have the new demodulator for testing, what test regime will you have?. Not knowing your setup, I have to make certain assumptions. One is that you would be using the new demodulator with the supplied cartridge and your existing set up with its own.

What equipment will you compare the new demodulator with and what test lps will you use, it has to be high end as Lou said the new demodulator will be the best ever. I suggest that recordings be made at 96K 24 bit (unprocessed of course) for members to compare first hand and evaluate any differences.

If anyone else has suggestions, please make them, it will be an ideal opportunity for John to do some serious testing before true production starts and iron out any possible wrinkles in the design.

Malcolm

23 days since my post and I seem to have killed this thread, no replies or suggestions.

I assumed there would be some interest in the new demodulator testing procedure, but it does not appear that way. I for one believe it should be tested against demodulators we are currently using at home, maybe a JVC 4DD-5 or a better choice would be a Technics SH-400 containg Lou's previous 'Best Ever' QSI5022 chip. Also since Jon is responsible for the testing regime we need to know what equipment he is using, it is meaningless to say it is "better", better than what? a cabbage, there needs to be some objectivity in the testing process. We are all going to be paying $500 + for this, we should know what we are getting and if it is measurably better than what we are using now.

I wonder if anyone cares?


Malcolm

 

[jefe1]

First Jon needs to get a unit to run tests on. I'm sure he'll let us know when that event occurs and be open to testing suggestions. It would be great if someone else could try out a prototype too. I mean I trust Jon but the more "beta testers" the better for all of us.
Your suggestions are good ones.

 

[JonUrban]

Malcom,

Sorry I missed your post from 23 days ago. I really don't check this thread that often.

I don't have a stock of other modulators to compare this one with. I have some selected LPs, I will be using a cartridge that Lou is sending, I plan to use my still sealed Soundbird Test LP to setup. I have Quadrafile and the Barry Manilow AQ-4090 which Nick Perugini says is the torture test for CD-4 demodulators. It will do video's if they work out as well as post audio samples and wav forms. I also have a Technics scope which, if it still works, I'll hook up.

However, I will not be comparing it to anything, as the only other CD-4 device that I have is my QRX-999 demodulator that QuadBob tweaked, but unfortunately he screwed it up somehow as now it does not work properly.

I'll post more when the thing gets here.

 

[Malcolm2010]

Malcom,

Sorry I missed your post from 23 days ago. I really don't check this thread that often.

I don't have a stock of other modulators to compare this one with. I have some selected LPs, I will be using a cartridge that Lou is sending, I plan to use my still sealed Soundbird Test LP to setup. I have Quadrafile and the Barry Manilow AQ-4090 which Nick Perugini says is the torture test for CD-4 demodulators. It will do video's if they work out as well as post audio samples and wav forms. I also have a Technics scope which, if it still works, I'll hook up.

However, I will not be comparing it to anything, as the only other CD-4 device that I have is my QRX-999 demodulator that QuadBob tweaked, but unfortunately he screwed it up somehow as now it does not work properly.

I'll post more when the thing gets here.

Jon, thanks for the reply. If I lived closer I would offer to send one of my own demodulators, however sending from the Uk would be difficult not to say expensive. You will have to do the best with what you have.

Malcolm

 

[loudorren]

Come One, Come All CD-4 Quadraphers alike,

Feast your eyes on the pre-production CD-4 demodulator that will soon ship to Jon. The printing on this unit was done with a Brother label maker. The finished unit will be silk screened epoxy paint.


Lou Dorren

 

[erniegiro]

Better than a centerfold! Hubba, hubba!

 

[Quad Linda]

And it does moving coil. :banana:

Linda
Turn on Your Heartlight

Better than a centerfold! Hubba, hubba!

 

[aludra]

love it love it love it

thanks lou

Mike

 

[jefe1]

Thank you, great to see it, and appreciate the clean design and all controls on the front face. And the input selections
Not a complaint, I am just wondering if its possible to get different colored meters, such as with a green background or some other color.
But thank you for sharing the picture and showing us that this is real.