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Old 5th February 2013, 05:13 PM   #34231
Mr. dB is offline Mr. dB  United States
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Quote:
Originally Posted by Kindhornman View Post
One of the reasons I never liked Ralph Nader was his attack on the Corvair. Why he did that but left the Porsche alone is beyond me, the same layout and the identical oversteering problems alike back in those days. If he hadn't done that we might have an American rear engine car today that would easily compete with today's Porsche.
The rear engine is not what makes a Porsche great, it's the engineering and quality. They could make a great car with any layout if they chose to. If you accept that the Corvette is America's greatest performance car, then there's no way that it can compete with Porsche's assembly quality. But then it's also priced a lot lower than an equivalent Porsche. It's absurd to think that a 2013 Corvair would somehow be an American 911.

Sort of like how Behringer could never make a Blowtorch...
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Old 5th February 2013, 05:27 PM   #34232
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Why not? I designed 30% of the new amp! You are deluded to think that I only make typical designs.
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Old 5th February 2013, 05:30 PM   #34233
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dB, right on! The Porsche 968 did a pretty good job of taking on the 911.
I believe in assembly quality of audio, as well.
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Old 5th February 2013, 05:35 PM   #34234
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Originally Posted by RNMarsh View Post
I am pretty sure that no one will ever be able to hear the affect of -120 of any additional harmonic with music.
I'm not that sure... IF the system noise is below -120dB AND IF the harmonic is of pretty high order (above the 7th i believe is needed).
120 looks good, though, I wish to reach that SNR first...
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Old 5th February 2013, 05:41 PM   #34235
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Originally Posted by Mr. dB View Post
Sort of like how Behringer could never make a Blowtorch...
Apples 0, Oranges, 1.
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Last edited by Esperado; 5th February 2013 at 05:52 PM.
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Old 5th February 2013, 05:48 PM   #34236
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Mr. DB,
While you are correct that German engineering is first rate bar none, do not discount American engineers in that regard. As far as back when we had the Corvair the Porsche was also a piece of crap. You can argue about the build quality now but back then the Porsche was an over-steering joke. I have raced enough cars and where I live we had a very nice illegal street course, Mulholland Drive, that showed who had what. I have seen more Porsche's over the side of the cliff than most any other car at the time. Going into a corner too hot with a Porsche with the limited rear tire size at the time switched ends rear fast! Today I would put the current Corvette engine, the hand built titanium rod, supercharged drive sump engine against any production engine around. It is a very high quality product even if the rest of the car does not reach the standards of others costing much more. I have heard this nonsense about American cars and designers for to long. It isn't the designers or the cars, it is the price point and the expectations of the bean counters, not the engineers in that regards. Back in the day I never saw a Porsche that could keep up with some of the hot rods we had. Yes they weren't stock, but they were more than fast enough to take money from the Porsche boys every time. Some of the cars we raced were far from street legal, CanAm Corvettes with aluminum engines were not to be messed with. Me I just had a '69 Z'28 with 4" of ground clearance, 10" of rubber in front, 13" in the rear, German Bilstein gas shocks made for me by them, Dick Guldstrand springs, custom sway bars and many other things to go with that. The engine only had an 8,000 rpm limit but that was enough to eat a Porsche's lunch. Believe me I had friends working on TransAm engines, Traco, and suspensions and we weren't typical shade tree mechanics. Porsche's and Corvair's of the early 60's were fairly close in what they would do if you had half an idea of what you had to do. When is the last time you saw a 356 Porsche on the street? I know a place here in L.A. where they have them stacked up like cord-wood, would make you sick, but they were just a pretty VW back then. The 911 has been a car that has had many upgrades, the engines are no longer air cooled, have turbo's and fuel injection, tires wide enough to handle the polar response of the engine weight and many years to get it right. I took two of my kids to the last auto show here in L.A. and my daughter got to sit in the latest Porsche's. Here response was that the inside of the car was boring. Me, I would take the Panamerica over the 911 as I just don't drive 120mph much these days. If I really had my choice it would be the Audi R8 or R10, though in the mid 80's you couldn't give an Audi away after they all started falling apart. They weren't much better than a Fiat of the time. I think you read to much of the auto press and there opinions, not much different than the audio press as far as most of us are concerned!
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Old 5th February 2013, 05:58 PM   #34237
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Quote:
Originally Posted by RNMarsh View Post
Hmmm. 10dB IS a big deal. As we can detect a level change of fraction of a dB in DBLT (F.Toole etal). I would think 10X would be a big deal. Many people though we were 10X worse.. instead 10X better. The hearing limits/thresholds keep falling.
Keeping it in perspective.

-RNM
10x is not really something significant when talking of things 10^3-4 x smaller. something yes, something significant? not in this context, by comparison IMO

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Originally Posted by SY View Post
This is frequency discrimination, not level or distortion. Humans can be extremely sensitive to pitch. Fourier uncertainty sets no minimum detection level for amplitude.
sorry you are correct, I didnt go back and check the article, was still stuck on noise from immediate conversation. I wont pretend to have any meaningful understanding of the math etc behind this article to argue.

on the other hand, out of curiosity isnt jitter ie phase noise still often measured in dB? couldnt any error/deviation in the analogue/frequency domain be called jitter when compared to an ideal reference recording or tone?

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Originally Posted by RNMarsh View Post
I am pretty sure that no one will ever be able to hear the affect of -120 of any additional harmonic with music. BUT, there is a tendancy to say if it can not be measured then it doesnt exist. And as we approach ever lower level of measurement sensitivity, the goal post moves ever lower for circuit designers;
Witness the IC OPA... ever lower and lower and always test methods to reach and go beyond. To no real benefit other than sales thru numbers?
that depends very much on the target market. for medical, deep space, Xray and sonar imaging (think OIL as well), radar, lidar etc etc you bet there is benefit. lots more money there that will continue to drive the state of the art forward vs. audio for audio's sake.

Quote:
I was once charged with the project to get rid of Tritium waste. The idea was to burn it and disperse it into the sky on a windy day thru a tall chimney. The scientist responsible for this bright idea got the Ok. Because, when it was mixed with the atmosphere, it would be so diluted that it could not be measured. And, I supposed that to mean if it couldnt be detected, then it wasnt actually there.
well I guess thats all the lawyers needed....

Quote:
Back when we couldnt measure thd below .01% we thought the amps were perfect below that number.

Maybe there is a need for perfection somewhere in this? Or the appearance of it?

Thx-RNMarsh
of course there is a need/search for the eternal, unattainable perfection
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Old 5th February 2013, 06:07 PM   #34238
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Originally Posted by SY View Post
I was just on a phone call with the CEO of a major car company talking about the problems they're having with their crankshafts. We've been working as competitors since 1964, when I showed them that they were doing their transmissions all wrong. This is the sort of thing my colleagues do between lunches at expensive restaurants. We discussed the fact that no one can tell Coke from Pepsi as well. Have you ever worked in a Pepsi factory? I certainly have!

I certainly can tell coke from pepsi.
Remember years ago the taste test.
I could easily identify which was which.
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Old 5th February 2013, 06:22 PM   #34239
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Originally Posted by myhrrhleine View Post
I certainly can tell coke from pepsi.
Remember years ago the taste test.
I could easily identify which was which.
I can tell the difference simply by re-imagining their tastes from childhood. My mother prefered Diet Pepsi.
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Old 5th February 2013, 06:23 PM   #34240
RNMarsh is offline RNMarsh  United States
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Quote:
Originally Posted by Kindhornman View Post
Mr. DB,
While you are correct that German engineering is first rate bar none, do not discount American engineers in that regard. As far as back when we had the Corvair the Porsche was also a piece of crap. You can argue about the build quality now but back then the Porsche was an over-steering joke. Today I would put the current Corvette engine, the hand built titanium rod, supercharged drive sump engine against any production engine around. It is a very high quality product even if the rest of the car does not reach the standards of others costing much more. I have heard this nonsense about American cars and designers for to long. It isn't the designers or the cars, it is the price point and the expectations of the bean counters, not the engineers in that regards. !
yep! A fellow car nut! I've been modifying everything I owned since my first car - a 1957 Chevy... put a freshened up sprint car engine in it for the street. The ZR1 is an over the top race car... and done on a budget! The head of the company asked, afterwards, I wonder what could be done with a $50K higher price? It is built in the Corvette factory but there is not a single part used from a Corvette. All hand built. GM could always do this - just needed the motivation. Just like VW could make a great supercar if desired. High-end isnt like nor should be compared with the standard product lines. [PS I have modified my ZR1, already for more power!.... Wretched excess, I suppose. But I love the complete and thorough engineering that goes into a high-end product... it isnt always just about numbers though. Ditto my CTS-V Caddy... upgraded suspension.. springs, sway bars, supecharger, inter-coolers, tuning ... . It never ends. Thankfully.]

Thx- Richard (Dick, Richy) Marsh
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