In addition to deterioration of the master tapes between the time the vinyl masters were cut and the same recordings were reissued on cd, the manipulation to get the recordings on vinyl were of great benefit. Among them were dynamic compression. As the signal gets lower, gain increases. This increases the amount of reverb at the end of each musical phrase. This is one area where the "air" comes from. Another is the 15 khz peak found in many phono cartridges that is absent in mainstream (cheap non audiophile type) cd players. Additionally, in the days vinyls were cut, many if not most studios equalized their monitor speakers sometimes on a weekly basis using calibrated microphones. While this did not negate all differences in their sound, there was much greater uniformity from recording company to recording company and there were far fewer of them. They also tended to use similar types of monitor speakers such as Altec A7, University, Utah, EV, and JBL horn systems. Today, equalization of cds is all over the map. I have to equalize each one individually or they sound horrible. Usually a dual 7 band equalizer works very well to compensate but it is tedious and time consuming taking many itterations sometimes.
A recording of Carol Rosenberger on Delos playing Water Music on a Bosendorfer sounded identical to my ears when the vinyl played on an Empire 698 with a Shure V15 type V MR was compared to the same recording on factory issued cd played on a Toshiba 192 khz cd player.
The superiority of the Redbook CD system over vinyl is easily demonstrated by the fact that even uncalibrated consumer grade equipment can burn cds from any vinyl that is a dead ringer or near dead ringer when compared with the vinyl. The opposite even using the best phono equipment cannot be claimed for obvious reasons.
Wow, I never knew that CD was so good! Where have I been? Shure V15? Will a Grace F-9E do the job, just as well?
In the annals of remarkable human endurance in circumstances of physical extremes which test the very fiber of which we are made, to the likes of such legends as Raold Amundsen who first traveled to the South Pole, Sir Edmond Hillary who was the first to scale Mount Everest there must be added unsung heroes such as those who were on the performing stage with the Grateful Dead enduring sound pressure levels of 130 db and more, not just once but repeatedly. Not only did they live to tell about it, what is even more remarkable that such persons could still hear anything at all.
Yes, I had a pleasant phone call with the mixing engineer for the Grateful Dead over about 20 years, just last week. We both joke that we still can hear pretty well. I met a roadie from GD (KID) at an AES a couple of years ago, and except for getting big, he was just fine, and we had a normal conversation. Amazing isn't it?
And here I am with normal to good hearing for my age. My associates and I must be very lucky. In any case, I am not building a $40,000 phono stage for no reason at all, any more than a Bugatti or a Bentley auto is made. It is to test the LIMITS OF PERFORMANCE of the medium, in my case, vinyl playback.
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many thanks, for hell-ping the USA, become a 3rd world nation
"perfect sound forever"
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What we have here, is an example of what I was trying to discuss with Scott Wurcer. It is a mental attitude, often based on assumptions, not proven, that doing anything that might be 'fun' is detrimental to your health and happiness.
Just this week, on American TV, a NEW commercial telling everyone that even lighting ONE cigarette will go a long way to destroy you, your children, and anyone else within close distance. What a load of ...., taking something that is not good for you and exaggerating it out of proportion, just to make a point.
It is the same with loud sounds. I will not say that they are good for you, but they can be part of an interesting experience. Do I regret that I did expose myself without earplugs on occasion? Yes, after all, audio is my business, and listening is all important. Did I ruin my ears? NO! Did my associates ruin their ears? They seem to hear OK, and they did 100 times more high level sound exposure than me. What is the problem? Now, would I recommend to my grandchildren to blast their ears with earphones? NO, of course not. It MIGHT hurt them, as I may have been 'lucky', just like just about everybody I knew who worked with the GD.
Just this week, on American TV, a NEW commercial telling everyone that even lighting ONE cigarette will go a long way to destroy you, your children, and anyone else within close distance. What a load of ...., taking something that is not good for you and exaggerating it out of proportion, just to make a point.
It is the same with loud sounds. I will not say that they are good for you, but they can be part of an interesting experience. Do I regret that I did expose myself without earplugs on occasion? Yes, after all, audio is my business, and listening is all important. Did I ruin my ears? NO! Did my associates ruin their ears? They seem to hear OK, and they did 100 times more high level sound exposure than me. What is the problem? Now, would I recommend to my grandchildren to blast their ears with earphones? NO, of course not. It MIGHT hurt them, as I may have been 'lucky', just like just about everybody I knew who worked with the GD.
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I think that if I had been exposed to a rock band repeatedly at ten times the loudness of the threshold of pain, I might have been grateful to be dead too. 
Hey didn't they do something like that to the prisoners at GITMO...and the Red Cross told them to cut it out? 
After that all they had that was next best thing was waterboarding 
Hey didn't they do something like that to the prisoners at GITMO...and the Red Cross told them to cut it out? After that all they had that was next best thing was waterboarding
We found that if you LIKE the music, it doesn't seem to effect you, except in a good way. In fact, we thought at the time, that this made the loud sound levels OK. I would not go that far, today, but here I am, and I can still hear audio differences, perhaps easier than my critics. This goes to show that when people lead with conclusions, without any evidence, they are often off track.
I would like to point out to everyone, that the high sound level is NOT directed in the high midrange, but in the BASS. It is to make the lower notes more engaging. Many other PA systems at the time, had very high distortion midrange horn loaded speakers. These speakers COULD be really annoying and maybe punch a hole in your listening spectrum. We avoided those, as much as possible, annoying JBL at the time. We wound up not using JBL horns and only used many, many, JBL direct radiator speakers, and of course, 1000's of watts.
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My pet hate is the cheaper disco systems that use those awful Motorola Tweeters with the 17 Khz peak of 116 db for 1 watt in, they give me tinnitus if I have to endure an evening of them.
Wrinkle
Wrinkle
The definition of what constitutes music seems to be a very personal matter. What is music to some people is noise to others. I don't think the military selected the type of recordings they exposed the enemy to at very high sound levels to entertain them.
Wrinkle, what is this 17KHz peak in the Motorola Tweeters? When I tested them 35 years ago, they were fairly flat in frequency response, even if they were 'brittle' sounding.
Back in the days that I worked with the Grateful Dead, I had a a pair of K-horns with Electrovoice T-35 horn tweeters. They had a NOTCH at 19KHz, and for years I thought that I had a hearing loss at that frequency, until John Meyer and I actually tested the tweeters and their big brother, the T-350, and found the notch in the tweeter itself in 1974. Let us ask Ed Simon about this.
Back in the days that I worked with the Grateful Dead, I had a a pair of K-horns with Electrovoice T-35 horn tweeters. They had a NOTCH at 19KHz, and for years I thought that I had a hearing loss at that frequency, until John Meyer and I actually tested the tweeters and their big brother, the T-350, and found the notch in the tweeter itself in 1974. Let us ask Ed Simon about this.
So you're not into shreikers and screamers, you prefer boomers. Thump, thump, thump. I guess a lot of people like that....jugding from the number of complaints to the police for disturbing the peace at night
....especially from apartment dwellers.
Sometimes I can almost feel someone else's car with the windows closed pulsating like it was a balloon, a machine with a throbbing headache. 
Didn't people used to go to deafening rock concerts back in the 1960s where they had these blinding flashing strobes at the same time? 
And then to make mind numbing sensory overload to the brain complete they took hallucenogenic drugs like LSD as I recall. 
Their guru
was a man named Timothy Leary who told them to "turn on, tune in, and drop dead.".....er, come to think of it, I think he said "drop out." 
There are certain things in life I cannot countenance. People who beat their wives and children, people who abuse their pets, and then worst of all are those who listen to piezoelectric tweeters. What they do to themselves is their business. But what they do to others around them....it's worse than second hand smoke.
😀
😀Motorola sold the tweeter business long ago, as far as I can tell you can't even buy them anymore. The copies that I measured rolled at 7,000hz! They were cellphone ringers repackaged to look like tweeters.
I don't know about a hole in the EVT35 response, it is only down 27db at 20,000hz and keeps on rolling. A good tweeter for 13,000hz but not much more.
The real issue is the change in measurement microphones. The standard 1" microphones used back then had significant directional issues. See http://www.bksv.com/doc/Bp0100.pdf for the Bruel & Kjaer 4145 which was THE standard then. Today almost everyone use a 1/4" mic to avoid those issues. The related problem is that the folks who make studio monitors once they knew the HF was really dropping off, could not correct it, because the recording engineers then complained the now flatter high end sound too bright, as they had become used to the rolled off ones.
Finally the Grateful Dead sound system may have hit 130db or the equivalent output as if it were a point source. As the source is larger than a point, no one even standing in front of some of the speakers gets it full blast. Then of course 130db fast reading "C" weighting is not the same thing as 130db slow reading "A" weighting. Osha goes by the later, claims to glory the former.
Simon, the T-35 can be relatively flat to beyond 20KHz, you just need to roll off the reflection bumps between 4KHz and 10KHz by using a 2uF cap ONLY for each tweeter, a trick developed by Paul Klipsch. This flattened it out, nicely. Now, let us not get into a 'contest' about measurement at the time. John Meyer and I had B&K 1/4", 1/2", and 1" measurement mikes that we used for measurement in our lab in Montreux Switzerland in 1974, when we MEASURED each and every tweeter that we could get ahold of. We settled for the EVT350 for our reference active PA loudspeaker, the JM/C that we developed while there. We had FFT capability and, as well, analog measurement that extended to 100KHz. We measured a number of units. I'm sure that a phone call to John Meyer can set you on the right course.
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Yes, Soundminded, those were the days! Loud rock music, LSD and easy women! It was something that you will never experience, but I did, and I liked it. (up to a point)
I went on to classical music after that experience, and married a violinist. That was kind of fun, too!
I went on to classical music after that experience, and married a violinist. That was kind of fun, too!
Let's not confuse on axis measurements with power response.
A 2uf cap would bring the tweeter in starting at 10k with approximately the inverse curve of the on axis rolloff.
Here is the data sheet http://www.pa-anlagen.ch/Manuals/Electro_Voice/Horns/EDS/T35A EDS.pdf
That shows it 15db or more on axis at 20k and if you look at the coverage figures it narrows a lot at even lower frequencies.
An on axis measurement with a 1" microphone would look pretty flat. That is why automated turntables with decent software became popular. Of course the software most folks use today has only been available since September 2007. Before that there were a few programs that addressed part of the needs, but no single source solution.
As an automated measurement using multiple microphones can take a day or two, doing it manually for the same level of accuracy would take weeks!
For just getting a feel though I will use my golden oldie B&K first generation SLM with the IEC filter set and walk around to note the -6db points.
Also I remember the first Meyer brand designs with the funny cornered horns, followed by the level dependent variable crossover frequencies. A bit of a problem when your pattern control shifted with level, talk about sudden uncontrolled feedback!
So John loudspeaker measurement is still a work in progress. (Distortion ratings are very slowly in the works!)
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