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RE: On the other hand...

Posted by JURB (A) on July 7, 2016 at 16:31:37

In Reply to: RE: On the other hand... posted by BigguyinATL on July 7, 2016 at 12:23:52:

"why FTC power ratings tell a little about the capacity of the amplifier to survive a burn it period and then perform "warmed up" "

Oh that's the other thing, most new amps cannot withstand that warmup. It is one third rated power into rated impedance of a constant sine wave. Almost everything on the market will go into thermal shutdown, and this has been true for quite some time.

Bunch of wimps.

I DO realize if they built things like in the old days it would all cost a few grand. But I did not cause the inflation.

Actually there is no such thing as inflation, it really is the devaluation of the money. I read an ad, I think in 2000 that claimed that the same amount of gold that would buy a new car in 1900 would buy one in 2000. Now gold values are depressed because they are selling paper gold certificates which makes it look like there is more gold on the market than there is. But the US was holding Germany's gold and they asked for it back and the US can't come up with it for a few years. Venezuela asked for theirs back and got it right away. Now there will be problems in Mali, with a joint French and US venture to "help" them. Guess why. They have gold. That is how they are going to pay Germany. They lie too, first they said it was there but, some bullshit. Then they said it was "leased" out. Leased out means they stole it.

This is why stuff costs so much. When I was a kid, people paid cash for new cars and even houses. Now they don't even pay cash for gasoline.

I know some of y'all in here have money or make really super good money, but the schmuck making fifty grand a year is suffering. It is not even middle class anymore if you got a couple of kids.

If you wanted an amp of the build of say a Phase Linear 400/2, today of course it would include a speaker relay and protection which costs all of about ten bucks. But what would the whole amp cost ? I'm thinking around three grand.

Even if the ratings are true, you ain't getting what you used to get. The craftsmanship involved, it simply does not exist anymore. There is nothing better than an old analog tuner and a big antenna trying to get distant stations. And you could tweak it and it would exceed its specs by quite a bit. Remember the specs on everything back then were the guaranteed minimum.

I got that Pioneer SX-850 out in the garage. It had a fried channel and burnt up the bias pot so I jumped that out, so at very low levels you can tell just a bit. I have no top or bottom cover for it. The phono preamp has a fault, the front glass is broken and the tuning shaft is bent.

It is not for sale. It is rated 65 WPC but I am sure it puts out about 90. It puts out more than some of those amps at work that are rated, believe it or not, 3,500 watts. I'll tell you now, the brand Technical Pro is about the worst of them. Basically 55 volt rails that can do, IF the transformer can handle it, possibly 400 WPC into 4 ohms. (at 10 % distortion) It is a toroid BTW.

Now about those toroid power transformers, they are making them out of scrap metal. I have the transformer from my JVC JR-S600 (kinda rare) and it is of fine quality, totally hermetically sealed and all that. These new things just have clear plastic on them. No shielding at all. They are not in the same class at all.

I do have to admit they come up with some cool circuits. The QSC has a split supply and take the speaker output from the junction of the two main filters. The collectors of the outputs are grounded, eliminating the need for insulators. However it does require a separate, well isolated secondary for each channel. But as a result it cannot put out DC but does not suffer as much from phase shift and loss of power bandwidth as the old SESAPP capacitor coupled circuits. And requires no protection relay because it is incapable of putting out DC, even under ant fault condition. A power transformer secondary would have to short to chassis ground for that to happen and the odds, well Slim left town.

Crown has a pretty unique circuit they call a grounded bridge. It also requires a separate secondary for each channel but actually NOT a split supply. And it CAN put out DC. Info is online for those technically inclined.

I have been told that some Behringer amps are like the QSC. Supposedly the Crown grounded bridge patent still applies so it is unlikely anyone else will be building them until that expires. As far as I know, Behringer does not lie. In fact Yamaha's pro equipment does not lie as far as I know.

Now when you are talking good quality pro equipment, it CAN survive the old preconditioning at 1/3 power for an hour. But most of it uses fans. Many units do have fan speed control so that if you use it at home to listen to Mozart you will not be bothered by the noise. Cheaper units just hook the fan to the 12 volts and be done with it. That causes fan failures, and sometimes subsequent amp failures.

Another thing, sometime in the 1970s, they changed how they measured the horsepower of a car. Before it was on a dyno, engine all alone. Later it was measured at the drive wheels. People who are into math and engineering can see that this makes the numbers better. See you have torque and horsepower. Both measure torque but the horsepower measurement includes the RPMs, while the torque does not.

What that means is two engines of the same torque and horsepower rating could perform vastly differently. I remember two Vette engines, one a regular Chevy and the other made by Mercury Marine. I do not remember the exact specs so these numbers are strictly illustrative : (sp)

1. 350 ft/lb at 2,000 RPM, 350 HP at 4,200 RPM
2. 350 ft/lb at 1,700 RPM, 350 HP at 6,200 RPM.

Which engine is faster ? And to someone who can do the math, he can draw the torque curve from those numbers, at least fairly accurately. My math tutor probably can. I am teaching him electronics and he is teaching me math. He has become enthralled with test equipment and scopes and I want better math skills so I can design better. And we party while we do it. Whoever talks that day, talks. We do have arguments, especially about interruptions. He is talking about isomorphisms and I interject to ask if the reactance formulae are isomorphisms. They are, it is the same for inductors and capacitors but the capacitors are an inverse function - of the same thing.

Anyway, I have known for a long time how numbers can lie. It is just a matter of excluding the factors you do not like. While I do not deny global warming, I doubt what they say that it is all manmade. There is such a thing as the Malinkovich cycle, which has been worming this globe for a long time and has just passed its peak of doing so. And I do not deny that burning all this stuff warms the place up, that would be stupid. What I dispute is the extent of how much is anthropogenic and also, what the hell we can do about it. We cannot just scrap all the cars and pay a hundred grand for an electric car and build hundreds of nuclear power plants overnight to charge them. In other words, in current technology there is not viable solution. And all the government knows how to do is tax, ignoring the fact that China and other countries are going to spew CO2 just like always, just on the other side of our fishbowl. Carbon credits, they should be shot.

That is why I like to save older equipment. Alot of work and effort went into those things and unless they are really wasted they do not belong in a landfill. And in fact, even if they are really wasted they have good parts for units that aren't.

I am no longer into restoring old TVs, but that is because I see no good use for them. But audio is a different story. It started almost the same time as electronics period. "Watson, come here I need you". Television was a wonderful thing but they wasted it. I remember we had five channels and had to discuss what to watch, now we got 500 channels and there is nothing to watch.

I better just stop now. I would like to be in 1975 right now, but I know that time travel is impossible. And I hope it stays that way because the potential for abuse is just too great. Like Einstein said he would have never helped the US get the bomb unless he was sure Germany would have. In fact, I think after that he held back a few things. For the technically inclined who like fiction, check out a book called "The Final Theory". It is about him getting to the end of the equation and through his findings a weapon based on a cyclotron could cause an explosion anywhere in the universe without firing a single projectile. Of course some decent intrigue followed. I read it and really wished they would make a movie out of it. And it would not even take too much special effects. I can't f... stand special effects. Nothing has any damn plot these days.

And, my last bitch, with all this total garbage they charge you like $70 a month for cable ! At that rate there should be no commercials on ANY channel. I heard in some parts of Canada cable is strictly pay as you go. The technology reports what channel you watch, like HBO or Showtime or whatever and you only get charged for the time you watched it. Here, you pay for 500 channels but you can only watch one at a time.

Don't wonder why I am half nuts, wonder why I am only half nuts. This shit SUCKS.

Edits: 07/07/16 07/07/16

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