Vomit fried amplifier and infrared seeking cat.

May 04, 2014 45 Replies

I had to look that up before I posted it. I don't have an active 70 volt system with which to measure. It's my understanding that it's

70.7 Vrms and 100v peak. However, when Googling for 70 volt rms/average/peak, I found that most references don't bother to make the distinction and simply call it 70 volt. For example, the Wikipedia article doesn't mention rms/avg/pk at all. So, I did a quick skim of the available articles, tried to jog my memory of measurements I did maybe 30 years ago, and made a guess(tm) that it was 70.7v rms because the math works out so neatly for 100v peak. I have some books which might have the answer, but I don't have time to dig through them right now. Does anyone know if it's rms, average, or peak?
Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

shorted winding. "

Actually more like as if it was air core, or close. Pretty much the same thing.

I would guess that a good part of the voltage I was geting was because of the inductance of the second secondary.

This Rane article says RMS.

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NO. If they were, why would they be called 70.7 V? 70.7 is the RMS voltage when the amplifier is at full rated output.

Anyone wanting to run for any political office in the US should have to have a DD214, and a honorable discharge.

I kinda thought that but never really looked into it. Had no call to.

So it is 100 volts peak. Makes sense, and it makes sense that the taps on the transformers all over the place are marked in RMS watts.

It could have just as easily been done the other way, it just wasn't. Unless you know specifically, which most people have no reason to, it would seem just as logical for it to be 70.7 peak, which would be 50 RMS.

Maybe you should update that WIKI page.

No, they're marked in continuous average watts. Watts are not RMS. Amps and volts are.

Every stereo amp worth a s*it is rated in watts RMS.

(V*.707)^2/R

Of course the current goes down with the voltage but that's a given. Maybe the world is using the wrong word, but it certainly wouldn't be the first time.

Maybe the world is using the wrong word, but it certainly wouldn't be the first time.

Most if not quite all rms watt ratings are based on single frequency or two frequency sine wave test measurements. Not all that realistic for actual output in normal operating signals. Use for comparison purposes only.

?-)

All the talk about cats reminded me of this story I found somewhere:

her pet on the table, the vet pulled out his stethoscope and listened to th e bird's

After a moment or two, the vet shook his head and sadly said, "I'm sorry, y

"How can you be so sure?" she protested. "I mean you haven't done any testi

rned a few minutes later with a black Labrador Retriever. As the duck's own er looked on in amazement, the dog stood on his hind legs, put his front paws on the exa mination table and sniffed the duck from top to bottom. He then looked up a

The vet patted the dog on the head and took it out of the room. A few minut es later he returned with a cat. The cat jumped on the table and also delic ately sniffed the bird from head to foot. The cat sat back on its haunches, shook

The vet looked at the woman and said, "I'm sorry, but as I said, this is mo

k the bill. "$150!" she cried, "$150 just to tell me my duck is dead!"

The vet shrugged, "I'm sorry. If you had just taken my word for it, the bil l would have been $20, but with the Lab Report and the Cat Scan, it's now $

First, there's no such thing as an RMS wattage rating. The correct term is "average" or "continuous average". RMS applies only to voltage and current.

Second, if an amplifier can put out a peak voltage of (say) 50 volts, then that voltage applies to any waveform within the amplifier's bandwidth, be it sine wave or music. There is nothing "unrealistic" about expecting the amplifier to produce an output of 50 volts peak, and deliver the corresponding power into a non-pathological load.

This discussion could easily veer into claims about "instantaneous peak power" or music power. Let's avoid that.

I think this is getting into the realm of splitting hairs about terminology . You know words are fluid in meaning, otherwise the Constitution would sti ll be in effect. It is not. (emergency powers, Admiralty, let's not go ther e right now) As a lawyer said, it doesn't matter what it says, it mattwers what the court says it says.

When I have an amplifier and pput a scope on it and crank ity all the way u p, where the waveform flattens at the top and bottom (clipping) occurs at a certain voltage. I take that voltage's peak value and multiply it by 0.707 , then square it and divide by 8. I then declare that number to be how many watts it puts out.

This differs from certain other figures that have been used. Like PIP. Peak instantaneous power. They forgot the "ILS". Peak instantaneous power if li ghtning strikes.

My amplifier clips at about 82 volts,plus as well as minus. Ergo, 80 * 0.70

7 = 56.56. Squared that is 3199.0336. Dividing that by 8 yields a figure of 399.87, give or take.

That is the peak value of the biggest reasonable facsimile of a sine wave i t will be able to reproduce. If that is not RMS power, I really do not care . Whatever it is, there is a 0.707 in there. Simply taking the peak power w ould yield a figure of 840.5 watts.

It's rated about 210 watts per channel - "minimum RMS". Talk to BOb Carver about that. If the term is not technically correct, fine. If I tried just f or a few minutes I could find alot more wrong than just that.

Here's one : 180 degrees out of phase. I cringe, almost lock and load when I read about the output of a common emitter, source or cathode amplifier is 180 degrees out of phase with the input. That is ALOT wronger than RMS pow er.

If you want to shift the phase of a 1,000 Hz signal by 180 degrees what you must do is to delay that signal by a half a millisecond. It IS NOT the sam e thing as inverting it as any non symmetrical waveform will easily show.

That bullshit bothered me when I was 12 years old and I am glad that people don't say dumb crap like that today. I heard it too many times and electro nics teacehrs who taught it like that should not be allowed to fix a toaste r.

There is too much damn stuff to unlearn in life already, the last thing any one needs is more.

Yep. Perhaps it would be helpful if we got away from the audio stuff and took a look at what the RF sector is doing: Summary: RMS = average and there's no such thing as RMS power.

More:

If you search the FCC web pile for "rms power", you'll find that they use average power. There are references to using an "RMS detector" setting on spectrum analyzers and power meters, which they equate to reading the average power.

Rhetorical question: If there's such a thing as "true RMS", is there also a "false RMS"?

Gone to clean up the workbench. I haven't seen the table top in months.

Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

also a "false RMS"? "

Answering rhetorical questions is my middle name ! lol

One of my favorites is "What mode is Windows in when it is NOT in safe mode ?".

Anyway, since you use the sine of 45 deg before squaring the voltage, the a nswer comes out to less than .707 of the - I guess - peak power. If you too k the peak voltage squared and then apply that 0.707 to it, what do you hav e ?

Technically if all amps are measured the same who cares ? There is alot of terminology that is incorrect, and when correct they want to change it anyw ay.

Like not so long ago, macula. WTF is macula ? So I figure out what they mea n. They mean fovea. Well why the hell didn't they just say so ?

Another thing is that I doubt the claim could actually be made that there i s no such thing as RMS watts. Watts are a product of voltage and current. T his is a number. It varies. If you took and sampled it at a bunch of points of the waveform, and literally root mean squared it, what would that be ?

You've 16 and 25. The square roots are 4 and 5 respecrtively. the mean betw een them is 4.5. The square of 4.5 is 20.25. It is a number. Maybe I am stu pid or something but I do not understand why RMS cannot apply to it.

Of ocurse maybe thaatt's not what we're measuring here but then it's not li ke AGW where there is money involved. Well maybe...

Money can be involved in the strangest things. Getting ten percent more (of whatever variety) watts out of an amp might make it sell better. People do not realize that to get it any louder you generally need to about double t he power. And then distortion. Say you have an ampt that puts out 150 watts per channel with less than 0.05% distortion.

I'd like to see the speaker that plays at 150 watts input with distortion e ven below 1%. Find one and it is going to cost a shitload of money. It's no t likely to come from Best Buy. (culd though, but don't hold your breath)

So if you really can't stand the term RMS applied to power, I'll just use w atts period. You can assume that it means (Vp*0.707)^2/R.

Hmmm. "V P point seven oh seven sqared over R"

Sounds better than "average". that's probably why the audio industry decide d to use RMS, average just sounds so... ... ... average.

I love speaker power ratings. What they really refer to (or are supposed to refer to) is the biggest amplifier you can use without driving the speaker into audible distortion (below clipping).

Welcome to Obamacare!

Anyone wanting to run for any political office in the US should have to have a DD214, and a honorable discharge.

What is /that/ supposed to mean?

If you mean that /any/ form of medical insurance will be abused by doctors and hospitals, I agree wholeheartedly. If you mean something else, say it outright.

This country has argued about universal healthcare since Teddy Roosevelt's administration. (TR was, of course, a dangerous far-left radical determined to wipe out Americans' freedoms.) Had a public debate about universal healthcare begun after WWII, we would probably have a better system that everyone (other than those to the far-left and far-right) could agree on.

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By the way, I am very much against "socialized medicine". Medicare and Obamacare are not socialized medicine. My United Healthcare rep believes the federal government will eventually take over healthcare -- though he did not elaborate in what way.

Americans are irresponsible idiots. They let government make important decisions -- the complain they don't like them.

All I know is that the ACA solves NOTHING. Hospitals and doctors price gou ge and the solution is for more people to pay them ? While they kill 200,00

0 to 300,000 people a year ? And I mean kill, not minor screwups on people who were about to die anyway, I mean medical mistakes that kill people who should not have died at all. This is from the AMA's own figures.

People say the Dr Joel Wallachis a quack but that is not true. It is true t hat he did market a very good suplement tro people who, quite frankly, woul d have little use for it because they were too damn old. the damage had bee n done. the mineral deficiancies had already taken their toll and it really was too late to do anyhing but sotp further damage, that is if they hadn't ceveloped malabsorption by that time.

He said the if vets took car of people and doctors took care of animals tha t healthcare for a family of four would be twelve bucks a month but hamburg er would be a hundred bucks a pound. (or some numbers like that) I, very se riously here, would like to know a vetrinarian who would break the "law" an d treat me. They are much more competent than human's doctors when it comes to disease.

In the animal husbandy profession, they cured alot of the dieases that make them a s*it ton of money when humans get them. They used to get insulin fr om pigs' pancreas' because it was close enough. Before that, pigs got diabe tes. They found that the lack of trace minerals chromium and/or vanadium ar e responsible for diabetes in pigs, and they gave them supplements accordin gly. Without this, they would not live to market weight. IOn other words th ey get paid for keeping things helthy, not the other way around. A whole bu nch of other diseases have already been traced back to poor soil, and while they let humans suffer instead of telling them, they have to fix the anima ls.

I have studied this for decades. If you want a synopsis of the situation, i f you can reasd critically and have the time, I will supply you the files r roight here, which has NOTHING to do with Wallach or ANY seller or anytithi ng of ANY product whatsoever.

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this is from a book, in Australia, where doctors do not get rich on human s uffering. It is also quite old, but nutritional needs do not change. It lis ts what each of about 20 minerals do in the body, gives some information on what happens when it is deficient, and lists some sources. It also give a caveat on those sources saying that the levels "depend upon the soil in whi ch it is grown". It's an interesting read, broken up into sections that ope n in a new window. It also has zero flufff so you don't spend a month on i t. Go ahead and download it, but the "buy the book" link does not work. I W OULD buy the book. I only saved part of it.

The US government was aprised of this condition back in the 1940s or so but did nothing. However, there isno reason to hold them responsible. Ther eis nothing that can be done except to pay through the nose for free range and organic foods and even that might not work. The best bet is mineral supple ments. Plus, when they supplement the livestock and we eat it, we indirectl y get the benefit of those supplements.

It would be highly cost prohibitive to fertilize the land comprehensively. Therefore, since they get paid by the pound, they fertilize the ground with only what the plants need, which varies. That's why some things will grow in some places but not others despite a very similar climate. It boils down to the minerals in the ground, or more aptly put, boils up.

It changed my whole outlook on food and while befroe I was suffering from c hronic back problems and very bad knees to the poiont that walking down a f light of stairs was excruciating, to the point where none of this gives me any problems at all. I also look at most of my friends my age who have no t eeth and no or grey hair and am surprised at how old they look. I have neve r lost a tootha nd haven't seen a dentist in about forty years. I have a f ull head of hair and the only grey I have is in my beard, stangely right be loew where I got shot in the face in 1985.

In short, the ACA, which I refuse to call Obamacare, has done absolutely no thing to fix any of the REAL problems that cause the US to be among the lea st healthy yet pay the most for health.

The food pyuramid oi s a total joke. Since plants are nothing but carbopn, hydrogen and oxygen these days, carbs are stuffing. Stuffing is for dead tu rkeys and the facyt is that even they cannot live on it. In fact, they tout turkey as healthy because of low fat, which is bullshit. Fat does not beco me fat in your body, and there are things you NEED that are fat soluble. Wh at becomes fat in your body are carbs and sugars. These days, oyu can live without them, much better I might add. Part of what fixed me so many years ago was to limit carbs to almost nothing for a few years. I grew stronger a nd stronger feeding my body with proteins, mineral supplements and so forth . I didn't eat a piece of bread for about three years. I had never heard of Atkins either.

So the idea is prevention, and what they sell you on TV and the web is all a bunch of garbage. The proiblem is not what IS in your food, it is what i s NOT. You can take some poison, your body can handle it and get rid of it, if you're healthy enough. Not that you should seek out poison or anything but...

Rant over. Look at the data if you wish. You can odwnload thoss 20 some pag es to your harddrive for offline viewing or to pass around on sticlks or di sks. I recommend it highly. I hacve found no resource that even comes close to the level of that.

Actually I probably did hear of it but did not buy the book so it had nothing to do with my decisions.

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Root-mean-square is a calculation method based on the mathematical characteristics of a sine wave. It is thus valid for _any_ unit of measure. Your persistent argument is about different suppositions from the start. I was only a teen and laughed at PMPO the very first time i saw it.

?-)

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