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

[Disclord]

Disclord, I take exception with your criticism of '70's analog and LP technology. Having owned and sold some high-end Quad and 2ch back in the day, I'll stand by 70's fidelity being great. In fact, despite the quantum leaps that have been made in the last 40 years, I'll put nearly everyone's old Quad gear against 90% of what's sold as surround today. The vintage gear sounds better. That seems diametrically opposed to my comments on the "What's Your Quad Receiver" thread. It isn't. I would rather own an upper line modern surround receiver than any 2ch or Quad '70's gear. I feel even more strongly about modern surround preamps and amps.

Play a 70's LP, homemade reel or cassette, or a 7 1/2 ips prerecorded reel, and you'll find some great analog fidelity. Things like 1/2 speed mastered LP's and dbx II n/r upped the ante for analog, but the technology was pretty great without it. In fact, beyond preamps/amps, early and mid-70's gear sounded way better than the late '70's stuff. It certainly had a better build quality.

There were very high fidelity recordings and components in the late '50's. Sadly, most people had console systems that couldn't realize it. I'd put my 7 1/2" Bell & Howell mono reel, circa 1961, against most modern stuff. My Dad gave it to me back then so I woudn't buy 45's anymore.

I'm gonna invoke my advanced age here: most people under 50 think fidelity began in the '80's with Pro-logic and/or CD. It began in the 50's with a concept called high fidelity. The term mono doesn't adequately describe the transition from tinny limited fidelity to full frequency response. From there, everything is simply a refinement: stereo, Quad, CD, digital, 5.1 or whatever technological breakthrough. Don't get me wrong, I don't care to listen in 2ch or mono if I don't have to. I wouldn't own 1000+ Quad and 5.1 titles if I felt differently. If you think I'm wrong, buy any Blue Note mono or 2ch SACD. Is there anything on them that wasn't on the master tape to begin with? If Steve Hoffman and co. magically made wheat from chaffe, then why couldn't they create that out of Armstrong's Hot Fives & Sevens?

70's hardware and software. It's all there, simply listen.

Linda
Have a Nice Decade

Linda, I was speaking specifically of the CD-4 system which was pushing the LP system to its very limits - and you had RCA making terrible CD-4 pressings and corners were cut with CD-4 demodulators that didn't decode the JVC ANRS noise reduction system properly, had loosely spec'd resistors and capacitors in the matrix sections (for cost saving reasons - same with SQ and QS decoders - in fact for QS, except for Sansui QS Vario-Matrix, no two QS decoders could decode QS the same as each other), etc... I wasn't referring to 70's high-fidelity in general. And you know my love for dbx II LP's and their superior sound quality to any CD reissue - that's why I wish dbx had been used on CD-4. JVC's ANRS was too flaky of a system and too sensitive to level and calibration errors - just like the later Dolby C. (some people think JVC's ANRS and Dolby C are related, but they are not - they were independently developed 10 years apart - ANRS in the early 70's for tape decks and infringing on Dolby's A and B patents, and Dolby C. developed grudgingly by Ray Dolby in 1980 to have an answer to dbx that could be used with high-quality tape decks, U-Matic and Betacam - but Dolby C is so level and frequency response sensitive, that the tapes sometimes won't even track properly on the deck they were made on!)

Have you heard the German Nazi mono magnetic tape orchestra recordings done in 1944? Their fidelity is AMAZING - while the US was still using LP transcription records and wire recorders. Here's info on them: http://theaudiocritic.com/plog/index.php?op=ViewArticle&articleId=39&blogId=1
And Capitol's 3 channel stereo 35mm mag recordings -they are outstanding. Stereo movie sound was higher quality too (and better/more realistically mixed).

 

[Disclord]

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.

 

[ndiamone]

....exaggerated separation (like drums on front left, rhythm guitar on right, bass on Left rear, and lead guitar on right rear). I like this kind of quad actually.

I do too, being I grew up listening to 4-track production stems long before there was even stereo LP's nevermind quad and that's the only way you could get separation in those days.

But really that kind of presentation is not actually a ``quad mix''. That's just a sort of ``they dubbed the 4-track production stems over to a quad master'' and just cut (or dubbed) from that.

As far as CD-4 not being very discrete compared to a straight-across dub of a Q4 or 4-track production stem, yes it's true which is why unlike in early stereo, you couldn't play two albums offset from each other and not have hardly any bleed-thru.

And why they tried UD-4 which basically replaces the limited-function matrix inherent in CD-4 with something that has some loose approximation of a steering circuitry. Yes I know, UD-4 didn't have any music in it's carrier wave, only steering signals a-la Disney's Fantasound, but there's a lot of greenhorns in here who need a simpler explanation.

To achieve what sounded like two unrelated mono albums playing side by side on either the Audio Fidelity or Bel Canto stereo demo disc from 1957 with minimal crosstalk, the test was cut with INCREDIBLY deep grooves compared to the rest of the side, like 110-120 uM or even deeper to accommodate a vertical signal that was maybe in excess of the lateral, when normal LP grooves top out at around 90.

Nevermind talking about a quad disc, if you had to cut even a STEREO disc with 110 or 120 uM grooves or deeper, all the way through with no variable depth or pitch, you'd be back to ten or twelve minute sides, i.e. not much longer than a comparable 12-inch 78 accounting for the microgrooves and the roughly half speed of an LP.

The only deeper groove than that I have ever seen was the old mono Grampian-cut London (or British Decca) singles in the 60's (Rolling Stones, Marianne Faithfull, etc) some of which top out at almost 150 that were designed to be LOUD and that's all.

But then remember, records back then were only two or two-and-a-half minutes long as well. Nobody in 1963 was trying to put Grand Funk Railroad's Destitute and Losin' (7:01) or Bruce Springsteen's Incident On 57th Street (10:03) on a single side of a 45. They had enough trouble in 1955 with the promo-only single of Billy Vaughan's Shifting Whispering Sands 1&2 on the same side of a 45, and that's A) only mono and B) only six minutes long. Even then, they had to cut it at like a minus 15 dB so if you wanted loud, forget it.

My dad gave me (the 1961 Bell and Howell reel to reel) so I would stop buying 45's.

Yeh my cousin Elaine was like that. All girls in her family except my cousin Danny who was born 15 years later after all the girls had pretty much grown up. So my Uncle Dan didn't have anybody to teach his hi-fi to, and by the time Elaine's first sister was born four years later, he decided he was gonna teach all the girls about hi-fi and cars and trains and...... hoping that they'd be as good as their future husbands at it.

Not only were they as good as whatever suitors they might have had, in a lot of cases they were better. But they were ahead of their time. This was the late 50's and early 60's, so any potential suitors were scared off.

Elaine went to join the union and be a mechanic for the post office and her sister Delores went on to be a stereo salesman and repair tech in Highland Stereo after 15 years as a longshoreman, selling college kids that would have been her son's ages their first good stereos.

They're all spinsters now. (LOL)
But we get along real good at like family functions etc so that's nice.

 

[Quad Linda]

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

I do too, being I grew up listening to 4-track production stems long before there was even stereo LP's nevermind quad and that's the only way you could get separation in those days.

But really that kind of presentation is not actually a ``quad mix''. That's just a sort of ``they dubbed the 4-track production stems over to a quad master and just cut (or dubbed) from that.

 

[ndiamone]

I like it "mixed" that way, especially discrete Quad rock/pop music. But... it's not a technically adept mix, or more accurately, no mix at all.

My favorite of those is the opening bars to the Jesus Christ Superstar original 1970 concept album in the brown jacket.

It was the only rock and roll album allowed in our house. My brother had to smuggle in his Hendrix, Joplin and Morrison LP's, but my mom had the JCS double LP for years. Then a friend of mine found a quad demo tape that spun the electric guitar around the room one bar at a time one channel at a time one way and the Moog ``answer'' in the opposite speaker the other way.

The rest of the track is conventional stereo with just ambiance in the rears - so except for the truly quadraphonic opening bars, I can do better rear-channel ambiance than that right here on my desktop. But I never seen that quad demo tape since or know what else is on it.

 

[See Why Audio]

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.

 

[Disclord]

...And why they tried UD-4 which basically replaces the limited-function matrix inherent in CD-4 with something that has some loose approximation of a steering circuitry. Yes I know, UD-4 didn't have any music in it's carrier wave, only steering signals a-la Disney's Fantasound, but there's a lot of greenhorns in here who need a simpler explanation.

Actually, UD-4 used a single frequency limited third channel on its single carrier signal and an optional fourth QMX signal for full 'quad' channel separation. Since we hear directionality best in the mid-to-lower frequencies, the UD-4 TMX carrier signal was band-limited to something like 5 kHz and was only a single channel carrier on both record grooves. So the main channels were the 2 channel BMX matrix that could be decoded with a BMX decoder or, with a full UD-4 demodulator fully decoded with the TMX or if provided on the disc, the QMX signal. The main carrier was the band-limited TMX third channel . When demodulated and de-matrixed, a channel separation of about 10db front-to-back and across the back channels was achieved. Due to the phase relationships and the basic BMX matrix, it sounded like four discrete channels since it was basically a Great Circle Ambisonic system, but without the problems that CD-4 had in carrying separate full bandwidth channels on dual FM/PM/FM carriers.

As Hi-Fi News & Record Review wrote: "...The reliance upon a limited frequency range greatly diminishes the frequency-band requirements for the FM channels to those which may be more readily accommodated in the present disc art - - without prejudice to future advances in the art-diminishing at the same time one of the major sources of distortion and noise to which such channels are otherwise prone. A second source of distortion, arising from modulating the carriers in a difference mode, has been virtually eliminated through choosing a constant-phase-deviation equalization scheme for that mode."

CBS SQ sort of copied this with their USQ system that carried a base-band SQ signal, and a third T signal for 10db front-back separation and full CF-CB separation and a fourth Q signal for fully discrete quad. Ben Bauer had developed it for both LP's and quad FM but withdrew from the quad FM race due to quads diminishing market - CBS wanted out of quad. Even without the two extra carriers, the system was officially renamed Universal SQ because the Position Encoder could encode any direction perfectly and SQ carried the full information about the 360 sound field and wasn't limited to 4 channel speaker feeds - and they (Ben Bauer, Greg Badger, Martin Willcocks) expected decoders to be developed like Ambisonics, where the user would tell the decoder how many speakers they had and the speaker layout and the decoder would derive the appropriate speaker feeds. So, for example, you could have 8 speakers around you with optimal imaging.

 

[Disclord]

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.

For information on how SQ is to be decoded correctly, read Martin Willcocks AES paper "Surround Sound In The 80's: Advances In Decoder Technology" = he explains the matrix algebra of SQ encoding and the algebra for decoding SQ correctly including the "B" matrixes for the matrix multiplier section of the DES SQ decoder. And the fact that his DES for SQ is a three-axis decoder so it can decode three simultaneous directions - unlike any other matrix past or present. Also read his 1985 patent for the Automatic Dimension Control for the DES - it goes further into the workings of the DES, as does the original DES patent, although the matrix equations are typeset badly in the patent. There's also a paper on my site by CBS - it's considered the most important paper written about SQ - the URL to read it is:
http://issuu.com/disclord/docs/synthesis-of-4-2-4-matrix-systems-1?mode=a_p

 

[Quadro-Action]

as completion to the first Stereo recordings in Germany: From 1943 to the late days in 1944 the sound engineers of the radio station "Reichsrundfunkanstalt" in Berlin has recorded already 200 stereo tapes (some mean even 300). Unfortunately kidnapped from the Soviets. Later by a return to Germany only a few stereo tapes was found. I have a CD with the first stereo recording of Herbert von Karajan. It is the 4th movement of Bruckners Symphonie Nr. 8 recorded 1944.

Dietrich

 

[Disclord]

as completion to the first Stereo recordings in Germany: From 1943 to the late days in 1944 the sound engineers of the radio station "Reichsrundfunkanstalt" in Berlin has recorded already 200 stereo tapes (some mean even 300). Unfortunately kidnapped from the Soviets. Later by a return to Germany only a few stereo tapes was found. I have a CD with the first stereo recording of Herbert von Karajan. It is the 4th movement of Bruckners Symphonie Nr. 8 recorded 1944.

Dietrich

In case you didn't read the link I posted, here's part of what Peter Azcel wrote about the 1944 German recordings:

"...but those are not the reasons I was excited. What is extraordinary is the 1944 recording—on magnetic tape, at 77.2 centimeters (30.4 inches) per second!
Sophisticated tape recording technology was unknown at the time to anyone in the Allied countries; the Germans had developed it and kept it secret until the equipment was discovered by the occupation forces after the end of the war. Even the latest and greatest recording projects of RCA Victor, Columbia, NBC radio, and other major American companies were on 16-inch 331/3-rpm acetate masters in 1944. The difference was night and day. The German magnetic tape recordings with high-frequency bias, moving past the heads at the high speed of 30 ips, were basically equal, or at least comparable, to some of today’s best recordings in frequency range, distortion, dynamic range, and noise floor. I could have been listening to a 2007 recording of Die Walküre, except that it was in mono. (Stereo became the standard in the late 1950s.) I couldn’t quite figure out the microphone setup; it could have been just a single mike; but the voices are always picked up fairly close, so that every syllable of the German text is crystal clear, much clearer than in modern stereo recordings. Perhaps it was the superior acoustics of the opera house. The orchestral sound also has great presence and timbral accuracy."

WOW!

 

[Quadro-Action]

Hello disclord, of course I have red the linke. That was the reason for my answer. In the link was told: "Die Walküre", except that it was in Mono (Stereo became the standard in the late 50's)... And I find it interesting by reports about early recording technics to write, that there was already stereophonic recordings in 1943 and 44. I can't find a mistake in my message.

Dietrich

 

[Disclord]

Hello disclord, of course I have red the linke. That was the reason for my answer. In the link was told: "Die Walküre", except that it was in Mono (Stereo became the standard in the late 50's)... And I find it interesting by reports about early recording technics to write, that there was already stereophonic recordings in 1943 and 44. I can't find a mistake in my message.

Dietrich

I apologize if I made you think you had made a mistake - I just didn't know if you were replying generically to my original post or if you had read the link - that's why I posted it the way I did. I'm sorry for any misunderstanding.

Have any of those 1944 stereo recordings ever surfaced or been released on CD?

 

[Quad Linda]

Why did the Nazis keep their tape recorders a secret? So that they could use them to create disinformation through live sounding recordings. audio doppelgangers!

Disclord, I apologize if I implied you were naiive or uninformed. I know you are not. You are mega knowledgeable. Most people today don't know a damn thing about hi-fi and have never even heard it. Many think great sound started in the theatre or with CD.

ndiamone, my Dad had a marginal hi-fi habit, which is why he bequeathed me his reel-to-reel. By 15, I had surpassed him with what I knew and owned. I commanded his respect by brandishing my trusty Ungar (Felix?) soldering iron. lol!! I had over 100 stereo LP's and two cassette decks by that age. Instead of him dragging me to Allied or Olson, I was dragging him and/or Mom. I'm very feminine, but love all this stuff. Some of my girlfriends ride motorcycles and pursue masculine interests. I'd rather get a mani/pedi than work on a vehicle, or even electronics at this point. I go CD/LP/DVD shopping far more than I go clothes shopping. It's a sickness.

Linda
What was this thread about again?

 

[Disclord]

Why did the Nazis keep their tape recorders a secret? So that they could use them to create disinformation through live sounding recordings. audio doppelgangers!

Disclord, I apologize if I implied you were naiive or uninformed. I know you are not. You are mega knowledgeable. Most people today don't know a damn thing about hi-fi and have never even heard it. Many think great sound started in the theatre or with CD.

ndiamone, my Dad had a marginal hi-fi habit, which is why he bequeathed me his reel-to-reel. By 15, I had surpassed him with what I knew and owned. I commanded his respect by brandishing my trusty Ungar (Felix?) soldering iron. lol!! I had over 100 stereo LP's and two cassette decks by that age. Instead of him dragging me to Allied or Olson, I was dragging him and/or Mom. I'm very feminine, but love all this stuff. Some of my girlfriends ride motorcycles and pursue masculine interests. I'd rather get a mani/pedi than work on a vehicle, or even electronics at this point. I go CD/LP/DVD shopping far more than I go clothes shopping. It's a sickness.

Linda
What was this thread about again?

Linda, The Nazi's kept their magnetic recording technology a secret for the exact reason you stated - the Nazi's even did a "live" Christmas broadcast where they supposedly linked Stalingrad, Berlin and a U-Boat by radio - but it was all a fake pre-recorded on tape. It wouldn't have worked on disc because of the ticks and pops that all disc recording suffered from - and wire recording wouldn't have the fidelity. So that is why it was a TOP SECRET. (You speak German? Yes, I know a little German - he's sitting right over there.) [Sorry, bad movie-based joke]

And don't worry, I didn't think you were calling me naive or anything like that - I just figured that, as is typical for the internet, something came across wrong due to my poor writing skills, that you, through no fault of your own, mis-interpreted. Keeping everything clear in forum posts is hard work! Plus, you and I have PM'd and we both know about what the other knows - you know? Heck, since you joined the forum, you've learned me so much you'd have thunk I was actin prideful from all kinds of fancy book readin, which we don't set much store in.

One thing about your statement "Many think great sound started in the theatre or with CD." Many also think THX invented "high fidelity" stereo surround sound for the theater and home and if something doesn't have a THX logo, then it's not worth a damn. THX on amps, in the early days of the home THX program, did mean something though - an amp that passed the THX tests would never fail and would have truly transparent sound with noise levels below 100db - THX tested home amps at full rated power, with full frequency 2 ohm loads for 24 hours. If it failed in any way, it wouldn't get the THX certification. So many amps failed the THX tests that they started watering down the specs to where they are today - now they mean nothing.

Linda
What was this thread about again?

Sandwiches.

 

[Doug G.]

...
Linda
What was this thread about again?

FCD-4.

Female Compatible Discrete-4 and the new demodulator which will have wonderfully feminine surface mount components.



Doug

 

[Disclord]

FCD-4.

Female Compatible Discrete-4 and the new demodulator which will have very feminine surface mount components.



Doug

No, must resist from commenting.... must turn off router to prevent myself from commen

 

[Quad Linda]

THX is hooey! It's just money for Lucas, et al. I'm sure that will get a few nasty responses. My B&K preamp is 7.1 THX rated. I'm sure it exceeds all their earlier stringent specs, as do my 2 B&K power amps. http://bkcomp.com I bought this gear to have all the power I'll ever want and to operate in the Class A range in most of my listening situations. Class A operation, moving coil cartridges, tube gear (don't own any), CD-4, DBX II, SACD, DVD-A and Blu-Ray-A impress me, THX doesn't. Since I'm not a movie girl, I could care less. I sold lots of THX certified gear over the years. Again, big deal, BFD.

Sorry if I've offended anyone.

I'm a huge student of 20th century history, so I knew about the German magnetic tape gear. Wasn't it Telefunken and Agfa that developed mag recorders and tape? In fact, I'm watching "The Making of Adolph Hitler" right now on the Military channel. When the History Channel began, my then spouse said, "the 'H' logo stands for the all Hitler channel." I have Jewish and gay relatives that were killed by him. My Gentile relatives were screwed out of an inheritance by him, including a bank building in Dallas. Lawyers advised them that it was a futile effort. I'm bordering on a political post here, which isn't my intent. WW's I & II were absolutely fascinating, though both tragic.

Before joining QQ, I thought I had immense technical knowledge about this stuff. Most of the active guys here, including Disclord and Doug have proved how little I really know. At least I'm very knowledgeable about software and history of the hi-fi business.

Linda
With my CRS, I can't recall what this thread was about. CD-4 demogitators maybe? Do those demogitate 4 CD's at a time? kewl.

Linda, The Nazi's kept their magnetic recording technology a secret for the exact reason you stated - the Nazi's even did a "live" Christmas broadcast where they supposedly linked Stalingrad, Berlin and a U-Boat by radio - but it was all a fake pre-recorded on tape. It wouldn't have worked on disc because of the ticks and pops that all disc recording suffered from - and wire recording wouldn't have the fidelity. So that is why it was a TOP SECRET. (You speak German? Yes, I know a little German - he's sitting right over there.) [Sorry, bad movie-based joke]

And don't worry, I didn't think you were calling me naive or anything like that - I just figured that, as is typical for the internet, something came across wrong due to my poor writing skills, that you, through no fault of your own, mis-interpreted. Keeping everything clear in forum posts is hard work! Plus, you and I have PM'd and we both know about what the other knows - you know? Heck, since you joined the forum, you've learned me so much you'd have thunk I was actin prideful from all kinds of fancy book readin, which we don't set much store in.

One thing about your statement "Many think great sound started in the theatre or with CD." Many also think THX invented "high fidelity" stereo surround sound for the theater and home and if something doesn't have a THX logo, then it's not worth a damn. THX on amps, in the early days of the home THX program, did mean something though - an amp that passed the THX tests would never fail and would have truly transparent sound with noise levels below 100db - THX tested home amps at full rated power, with full frequency 2 ohm loads for 24 hours. If it failed in any way, it wouldn't get the THX certification. So many amps failed the THX tests that they started watering down the specs to where they are today - now they mean nothing.



Sandwiches.

 

[Disclord]

Linda: At least I'm very knowledgeable about software and history of the hi-fi business.

And that makes me worship you - so many quadraphiles, even ones who were there, don't have memories or didn't pay attention to the quad world at the time and so can't relate their experiences like you can.

BTW, you have Utah speakers - In my 1974 Hi-Fi mags there are ad's for Utah speakers - I've never, ever heard of them before! What happened to the company? And how did their speakers rate?

THX is a sad story - it started out legit theatrically, then $$$ entered into it soon it meant nothing - same with the home version - for the first year or so of THX home products, the THX logo stood for high quality and reliability - then it took a quick nosedive as $$$ considerations came into play and they began lowering their standards for certification - then they started certifying VHS tapes, computer speakers, and UGH, speaker/interconnect cable, which is a complete industry fraud and companies like Monster Cable and Kimber know it.

Sorry to hear about your family losses to Hitler. I own the whole "World At War" series on DVD and have watched every streaming program Netflix has on Nazi Germany. It's still something so monstrous that I can't wrap my mind around it - that people actually let it happen. When my mom and I went to the Anne Frank house in Amsterdam, we were about to go in when the whole thing hit me like a ton of bricks - that this is where she and her family actually hid for 2 years because of the Nazi's - and I got so upset and so sick that I couldn't go in. It was the strangest thing that's ever happened to me.

 

[Quad Linda]

Yep, I WAS there. Waited with bated breath for the new SQ and CD-4 hardware and software technologies. I remember when virtually every hot new Quad product hit. Went bonkers every week when a favorite album was released in Quad. And I got to play with every new piece prior to production, or at least when it first hit our store.

My Dad passsed a couple months ago. Among his treasures, I found a sealed DVD boxes of World at War & Victory at Sea that I'd given him. They're mine now, along with a VHS box of WAW. There have been many revelations since it was produced in the late '60's. It was the premier WWII doc at the time. It's still one of the best, despite it's omissions. Sir Lawrence Olivier showed simpatico while narrating. They should view it in EVERY 20th Century History Class. Victory at Sea is also great. I have all 3 LP's, the two Dolby Surround CD's and the Q8 of it's soundtrack.

Linda
Show Me Your Shibata Tip-Audio-Technica button passed out at '74 Summer CES in Chicago

And that makes me worship you - so many quadraphiles, even ones who were there, don't have memories or didn't pay attention to the quad world at the time and so can't relate their experiences like you can.

BTW, you have Utah speakers - In my 1974 Hi-Fi mags there are ad's for Utah speakers - I've never, ever heard of them before! What happened to the company? And how did their speakers rate?

THX is a sad story - it started out legit theatrically, then $$$ entered into it soon it meant nothing - same with the home version - for the first year or so of THX home products, the THX logo stood for high quality and reliability - then it took a quick nosedive as $$$ considerations came into play and they began lowering their standards for certification - then they started certifying VHS tapes, computer speakers, and UGH, speaker/interconnect cable, which is a complete industry fraud and companies like Monster Cable and Kimber know it.

Sorry to hear about your family losses to Hitler. I own the whole "World At War" series on DVD and have watched every streaming program Netflix has on Nazi Germany. It's still something so monstrous that I can't wrap my mind around it - that people actually let it happen. When my mom and I went to the Anne Frank house in Amsterdam, we were about to go in when the whole thing hit me like a ton of bricks - that this is where she and her family actually hid for 2 years because of the Nazi's - and I got so upset and so sick that I couldn't go in. It was the strangest thing that's ever happened to me.

 

[Quad 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