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CECE
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Re: amps VS. watts

Since we are dealing with POWER amplifiers, which need to deal with both voltage and current, which is power W, in order to provide max power transfer, impedance matching is necessary. Look under the Reative section of the explanation, not resistive, which doesn't pertain to loudspeakers. An audio amplifier is a power amp, not a voltage amp, not a current amp, not a servo amp, not an op amp. power. And thusly it is like it says like I said before a modulated power supply, impedance matching does matter. WHY does your McIntosh have taps to MATCH different load impedances? hmmmm, if impedance didn't matter, or matching it, does it use taps on tube amps> Please continue...............and can you find a definition of a dictionary in a dictionary? What about a definition of an encylopedia in a dictionary, or an explanation of both in an encyclopedia?

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Re: amps VS. watts


Quote:
Look under the Reative section of the explanation, not resistive, which doesn't pertain to loudspeakers.

I think the warning is still in place regarding Wikipedia; people posting there might not know any more about the subject than the people turning to Wikipedia for answers. Never the less ...

From your first link;


Quote:
Loudspeaker amplifiers
Modern solid state audio amplifiers do not use matched impedances, contrary to myth. The driver amplifier has a low output impedance such as < 0.1 ohm and the loudspeaker usually has an input impedance of 4, 8, or 16 ohms; many times larger. This type of connection is impedance bridging, and provides better damping of the loudspeaker cone to minimize distortion.

The myth comes from tube audio amplifiers, which required impedance matching for proper, reliable operation. Most of these had output transformer taps to approximately match the amplifier output to typical loudspeaker impedances.

From your second link;


Quote:
Maximum power theorem
From Wikipedia, the free encyclopedia
Jan Vigne
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Re: amps VS. watts

JV:

Quote:
In any event, I'm not clear how your post answers the original quesion of the thread which is, "I ve been told that amps were resposible for how much bass an amp gives out.Ive also heard that the more amps the amp had,the better quality it was.So 2 amps could both have 200 watts,but one has 20 amps the other 60.The 60 amp one would be much more costly and of better quality."


Quote:
Speaker impedance tends to fall as the frequency falls below 50Hz. This means that an amplifier with a higher output impedance will deliver less
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Re: amps VS. watts


Quote:

Your math further strays from reality when you divorce power from its components of amperage and voltage. We can point to a multitude of receivers and lower cost amplifiers with a low output impedance achieved through the increasing abuse of NFB which are unable to deliver sufficient current into a low impedance, high electrical phase angle load. While the math works fine for on paper calculations, faced with a real loudspeaker a lower output impedance does not guarantee more power nor does it always mean "more bass" and it is definitely not a given the bass quality will be "better" bass. This is what I believe the original question is trying to resolve. The op asks whether "more amps" makes the amplifier "better". The answer, IMO, still is not resolved by either on paper calculation of current or output impedance alone. One begs the other and neither by itself can begin to suggest which amplifier is better. The amplifier most capable of dealing with the load it is provided is the best amplifier for the situation. If the load is benign, then current is not the issue and output impedance is far less a factor in which amplifier might be better suited to the task. Only when amplifiers are asked to perform Herculean tasks does either amperage or output impedance become relevant. Therefore, the real question I find myself asking would be; why are we expecting amplifiers to perform Herculean tasks?

If the amplifier cannot drive enough current into a given load then its output impedance has risen.

Jan Vigne
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Re: amps VS. watts

Or, it is current limited to keep it from going up in smoke.

You really can't be suggesting a $129, 1200 watt 7.1 HT receiver that cannot deliver sufficient current into a real world loudspeaker is unable to drive a low impedance load simply because its output impedance has risen. You don't suppose the more appropriate reason for current limiting such an amplifier would be it just doesn't have a power supply capable of delivering sufficient amperage to low impedance/high phase angle loudspeaker loads?

Telling me its output impedance has risen is giving me a symptom of the problem. I am after the root cause of the problem. Rising output impedance is not the problem. Even if it were, this would only address issues of low impedance (with difficult phase angles) which is still a very small portion of the frequency response of a typical loudspeaker. Remember, the original question is whether the amount of "amps" an amplifier can deliver is a sign of a better amplifier. Just stating a low impedance does not receive as much power as a higher impedance is over simplifying the problem. A low impedance with a benign phase angle is still a relatively simple and easy to drive load for most amplifiers. If I have a four Ohm single driver its impedance is relatively stable and the electrical phase is virtually non-existent. How would that be a problem for a reasonably well designed and adequately built amplifier?

cyclebrain
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Re: amps VS. watts

I don't know the answer to this question, but just because a tube amplifier with a transformer coupled output has various taps labeled with different load impedence values, does that mean that the 8 ohm tap has that same output impedence or just that that tap works best connected to an 8 ohm load?

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Re: amps VS. watts

The latter. Though connecting to an alternate tap might produce what is considered "better" sound. It depends on the amplifier, speaker and listener as to which tap sounds best.

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Re: amps VS. watts


Quote:
Or, it is current limited to keep it from going up in smoke.

If its in current limiting mode its output impedance increases, thats how currrent limits work.


Quote:
You really can't be suggesting a $129, 1200 watt 7.1 HT receiver that cannot deliver sufficient current into a real world loudspeaker is unable to drive a low impedance load simply because its output impedance has risen. You don't suppose the more appropriate reason for current limiting such an amplifier would be it just doesn't have a power supply capable of delivering sufficient amperage to low impedance/high phase angle loudspeaker loads?.

It may have risen for a variety of reasons, lack of PSU capabilty, bipolar gain droop in the output stage, current limiting yack yack yack.... but its output impedance will still have risen.


Quote:
Telling me its output impedance has risen is giving me a symptom of the problem. I am after the root cause of the problem. Rising output impedance is not the problem. Even if it were, this would only address issues of low impedance (with difficult phase angles) which is still a very small portion of the frequency response of a typical loudspeaker. Remember, the original question is whether the amount of "amps" an amplifier can deliver is a sign of a better amplifier. Just stating a low impedance does not receive as much power as a higher impedance is over simplifying the problem. A low impedance with a benign phase angle is still a relatively simple and easy to drive load for most amplifiers. If I have a four Ohm single driver its impedance is relatively stable and the electrical phase is virtually non-existent. How would that be a problem for a reasonably well designed and adequately built amplifier?

Its a cause, you should ask why has the output impedance risen?

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Re: amps VS. watts


Quote:
If I have a four Ohm single driver its impedance is relatively stable and the electrical phase is virtually non-existent. How would that be a problem for a reasonably well designed and adequately built amplifier?


Quote:
Its a cause, you should ask why has the output impedance risen?

What? You get to ignore a question just to give a set answer? How do I discuss anything if the only answer possible is "rising impedance"? This seems to be a circular discussion where the only answer is the same to all questions.

"When did you stop betraying the dictator?"

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Re: amps VS. watts

Hi guys
When does this thread come out in paperback? -- I must buy a copy

Jan Vigne
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Re: amps VS. watts

Buy the encyclopedia version. It has definitions.

cyclebrain
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Re: amps VS. watts

Russ is completely correct. Any reduction in output power is due to some kind of output resistance. It can be in the speaker cable, the amplifier output circuit, the output drivers, the power supply filter, the power supply transformer or even the wall outlet.

Try doing some simple ohms law calculation using a simple series circuit consisting of three components.
1) a voltage source
2) an output resistance (our variable)
3) a load resistance

Show me any answer other than maximum power to the load with the output resistance being zero.

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Re: amps VS. watts

What's the definition on an encylopedia?

CECE
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Re: amps VS. watts

Zero resistance is a short, nothing but full current then poof! With zero resistance you can't develop a volaatage across anything..if all you have is current and no voltage, how can you have power Since P=EI...but is there really anything with zero ohms, that would be a super conductor, which ain't in audio yet, only super hearing. And depending on the angle of when the conduction occurs also defines the max current at that time. Ya can't use Ohms law in reative ckts like a loud speaker, what's the freq Kenneth?

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Re: amps VS. watts


Quote:
What's the definition on an encylopedia?

I thought that no one would ask.
en from the word enclosed.
cyclo meaning wheeled vehicle (unicycle, bicycle).
pedia meaning two legged. (pedestrian)
An encyclopedia is an enclosed two legged wheeled vehicle.

Your welcome.

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Re: amps VS. watts


Quote:
An encyclopedia is an enclosed two legged wheeled vehicle.


I want one!

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Re: amps VS. watts


Quote:
What's the definition on an encylopedia?

Look it up. It's in the dictionary and you know how to spell the word.

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Re: amps VS. watts


Quote:
Russ is completely correct. Any reduction in output power is due to some kind of output resistance. ... Show me any answer other than maximum power to the load with the output resistance being zero.

That's all well and good but it doesn't address the original question or anything other than the momentary low impedance load an amplifier might see at a specific frequency. Being correct is not being relevant to the discussion.

Let's try these again.

A low impedance with a benign phase angle is still a relatively simple and easy to drive load for most amplifiers. If I have a four Ohm single driver its impedance is relatively stable and the electrical phase is virtually non-existent. How would that be a problem for a reasonably well designed and adequately built amplifier?

Tell us how many three Ohm speakers are on the market.

If an amplifier must have a low output impedance of roughly 0.02 Ohms to deliver full power to a load, how does an amplifier with a relatively high output impedance of 1.5 Ohms deliver power to any load?

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Re: amps VS. watts


Quote:

Quote:
Russ is completely correct. Any reduction in output power is due to some kind of output resistance. ... Show me any answer other than maximum power to the load with the output resistance being zero.

That's all well and good but it doesn't address the original question or anything other than the momentary low impedance load an amplifier might see at a specific frequency. Being correct is not being relevant to the discussion.

Let's try these again.

A low impedance with a benign phase angle is still a relatively simple and easy to drive load for most amplifiers. If I have a four Ohm single driver its impedance is relatively stable and the electrical phase is virtually non-existent. How would that be a problem for a reasonably well designed and adequately built amplifier?

It shouldn't be a problem

Tell us how many three Ohm speakers are on the market.

If an amplifier must have a low output impedance of roughly 0.02 Ohms to deliver full power to a load, how does an amplifier with a relatively high output impedance of 1.5 Ohms deliver power to any load?

It's a matter of ratios. The greater the ratio of the load relative to the source, the less effect load variation will have on power transfer to the load. As for the original question, I'm not really sure what it meant. Speaker impedance ratings are meaningless because of their variations vs. frequency.

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Re: amps VS. watts

May be helpful to this discussion

Please see a seminal paper here http://www.counterphase.com/stuff/Thiessen.pdf

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Re: amps VS. watts

THAT'S IT!!!!!!!!! See, amplifiers are basically power supplys, I said before, AND Impedance matching....shall I say......no magic, just basic electronics, electrical concepts. AND, they knew that in 1930!!! JV, see how they mention a matching transformer, like on teh McIntosh to impedance MATCH!!! No magic none of this, whatever you THINK sounds better, it's all electrical design, can be measured, documented, tested. Maybe it's a good thing JGH ain't writing anymore, he may have tried to make it all just imaginary personal preferences, when it's all measureable, and calculable. Ask Thiessen. Impedance matching, what a concept based in electrical parameters, not personal preference, imagination, and descriptive words that have no real clarity. Maybe Julian Hirsch had it right all along Also back to the origianl premise, lotsa watts, which means lotsa current, with the voltage to keep it going, that's called a great POWER SUPPLY, all else is not capable of hi fi.

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Re: amps VS. watts


Quote:

Quote:
If I have a four Ohm single driver its impedance is relatively stable and the electrical phase is virtually non-existent. How would that be a problem for a reasonably well designed and adequately built amplifier?

How do you define a reasonably well designed and adequitely built amplifier?. What specification do you think it would have?


Quote:
I did ask why the impedance has risen.

And you ave been given reasons


Quote:
Telling me its output impedance has risen is giving me a symptom of the problem. I am after the root cause of the problem. Rising output impedance is not the problem.

It is at the amplifier speaker interface


Quote:
If the amplifier's power supply is insufficiently stout to deliver current into a load, the probem is not a high output impedance since most of the cheapo HT receivers have more than enough NFB to lower T.H.D. to staggeringly low on paper levels.

You can still have a high output impedance and stageringly low THD figures


Quote:
So, let's discuss the problem not the result of the problem.

There is no magic bullet, no single problem. An amplifier is a complex interaction of components with conflicting requirements. A perfect amplifier should have zero output impedance, it may not sound bad if it does not but it would sound better if it did.


Quote:
>If high output impedance is the only issue here, no tube amplifier could possibly work into any l>>oudspeaker - taps or no taps. This infatuation with output impedance seems to be missing the boat> in so many ways and still does not address how this affects the speaker where its impedance is not three Ohms, where it is three Ohms but the electrical phase angle is benign, a more typical speaker system with a high impedance or the original question of the thread.

What do you think the output impedance of a typical valve amplifier is?


Quote:
>If you wish to persist in this idea that higher output impedance means less power delivered into a three Ohm load, tell us how many three Ohm speakers are on the market.

With two amplifiers with the same gain fed the same signal fed into identical non zero non infinite loads, the one with the lower output impedance will provide more power. Do you agree?


Quote:
>Otherwise, I think we've got the main points of low output impedance when doing equations on paper. Now let's move on to the other 99% of what amplifiers face when driving a real world loudspeaker.

Why do you think I am not thinking of the real world?

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Re: amps VS. watts

Seems we're back on the circular driveway again.


Quote:
How do you define a reasonably well designed and adequitely built amplifier?. What specification do you think it would have?

That was the original question of the thread, Russ. I don't think there is an ideal amplifier but I believe "reasonably well designed and adequately built amplifier" is explicit enough that we do not have to dance around words for a few more days. The question was about the load not the amplifier.


Quote:
I did ask why the impedance has risen.


Quote:
And you ave been given reasons

Given what preceded my reply, your response is jibberish.


Quote:
It is at the amplifier speaker interface

Maybe I'm wrong but I believe you have this backwards. If the amplifier had its way, its output impedance wouldn't rise and all amplifiers would be happy little creatures with a simple life. Of course, that won't happen since an amplifier must drive a loudspeaker to do its work. Therefore, if we are discussing a "reasonably well designed and adequately built amplifier", I don't believe the problem is rising output impedance of the source but rather it is falling impedance and reactive nature of the load. One is the problem while the other is the symptom. But merely stating a low impedance load as you have done does not suggest the speaker load makes life difficult for an amplifier.


Quote:
And you ave been given reasons

You are once again giving back a non-response. Try to keep the steering wheel straight so we can get off this driveway.


Quote:
There is no magic bullet, no single problem. An amplifier is a complex interaction of components with conflicting requirements.

That begins to answer the original question. All else is wasted verbage.


Quote:
A perfect amplifier should have zero output impedance, it may not sound bad if it does not but it would sound better if it did.

What do you consider "perfect"? An amplifier with the lowest output impedance in all cases? That would make life simple when choosing an amplifier I suspect though it would certainly lead to a lowest output impedance race amongst designers. No more listening as dup suggests. "Just give me the facts, m'am, lowest output impedance or not. Either it is and I buy or it's not and I walk." Goodbye tube amps, goodbye demo rooms and goodbye Stereophile. Once a year JA just prints a product guide with nothing more than the output impedance of each amplifier.


Quote:
What do you think the output impedance of a typical valve amplifier is?

To use your logic once again; what do you consider "typical"? A modern day tube amplifier? A classic tube amplifier? A high end tube amplifier? A cheapo from China tube amp? A push-pull tube amp? A SET tube amp?

I think we can both agree a "typical" tube amplifier's output impedance is probably going to be higher than that of a direct coupled solid state amplifier.


Quote:
With two amplifiers with the same gain fed the same signal fed into identical non zero non infinite loads, the one with the lower output impedance will provide more power. Do you agree?

A few days back I stated this argument is over simplification of the idea. I've agreed to the idea that a low output impedance will deliver more power to a low load impedance. I've disagreed with the concept of "power". Watts cannot be divorced from voltage and current. Speaking of only "power" or only "watts" is a discussion that belongs on paper in a first year engineering class.

Once again, here are my points.

If the amplifier is not faced with a low impedance load in a highly reactive loudspeaker, which amplifier delivers the most "power" is not the issue.

Not all loudspeakers are low impedance, highly reactive loads.

Whether or not a low output impedance can supply more "power" to a low impedance, highly reactive load is of minimal consequence when even those loudspeakers that are low impedance and highly capacitive loads at some point in their frequency response are only so through a very small portion of their frequency response. As impedance rises and electrical phase comes closer to zero, the amplifier with a higher output impedance is going to be capable of power delivery that is negligibly less than the amplifier with the lower output impedance. We are arguing over something that is only of value to a small portion of what the amplifier sees as a load.


Quote:
... the one with the lower output impedance will provide more power.

Is "power" then the only qualifier of quality in an amplifier? (dup, please don't go off on 1400 watts and SLAM.) That is close to the original question. If it is, and low output impedance gets us more power, the discussion is over since I cannot agree to those premises and I'm wasting my time here.


Quote:
Why do you think I am not thinking of the real world?

Once again to use your logic, you've been given that answer.

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Re: amps VS. watts


Quote:
If an amplifier must have a low output impedance of roughly 0.02 Ohms to deliver full power to a load, how does an amplifier with a relatively high output impedance of 1.5 Ohms deliver power to any load?


Quote:
It's a matter of ratios. The greater the ratio of the load relative to the source, the less effect load variation will have on power transfer to the load.

I understand that. The question of a high output impedance was rhetorical in nature since we seem fixated on the lowest possible output impedance. Some here seem to see this as an issue of the source while I prefer to look at the discussion as a matter of the load the amplifier works into. Mating the correct load to the appropriate amplifier seems to be the wisest choice IMO. If you prefer the sound of a SET with a high output impedance, finding the appropriate speaker for that amplifier is essential. If you feel only amplifiers with output impedance numbers in the triple naughts will do, then you've closed your ears to a great number of very good sounding systems.


Quote:
As for the original question, I'm not really sure what it meant.

Let me interpret the o.p. as asking whether all high current amplifiers sound "better" than a lower current device. Does the current capability of an amplifier dictate it's sound quality?


Quote:
Speaker impedance ratings are meaningless because of their variations vs. frequency.

That is exactly my point. Discussing whether a lower output impedance makes any amplifier "better" ignores too many issues where low output impedance is not an important consideration. Personally, I would rather have a very good sounding tube amp with 1.5 Ohms nominal output impedance and the appropriate speakers to mate with that amp than a cheap receiver with low output impedance derived by way of high N.F.B. ratios driving a low impedance, highly reactive speaker load.

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Re: amps VS. watts

Who's the webmaster of this board? Can we suspend Jan for spreading sheer boredom across these forums? How about for necrobeastabuse? At least when DUP rants, it's entertaining. Jan is like Chinese water torture. Perhaps we can shrink him, put him in a petri dish and just let him bask in minutiae.

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Re: amps VS. watts


Quote:
Your math works only for low impedance loads. This would make you correct if all loudspeakers were a consistent load - and all loudspeakers were low impedance loads. Since loudspeakers are not a consistent load, but are reactive as we've all agreed, your math only applies to certain frequencies at particular impedance loads. The ability of the amplifier with the lower output impedance to deliver more "power" into a 3 Ohm load is not relevant to what it can manage at all other frequencies which fall above 3 Ohms - which would be the majority of information contained in most music and where the speaker load tends to be more ideally resistive or rises to a significant degree


The Maths is actually correct for ANY load impedance (low impedance also occurs at mid-range frequencies as well). If you want to give me some specific numbers I

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Re: amps VS. watts


Quote:
That was the original question of the thread, Russ. I don't think there is an ideal amplifier but I believe "reasonably well designed and adequately built amplifier" is explicit enough that we do not have to dance around words for a few more days. The question was about the load not the amplifier.

Well a pretty case and made out of solid alumininum may pass your definition. How about a device that will give a voltage out proportional to the input regardless of load and with a constant time delay. Something like that?


Quote:

Given what preceded my reply, your response is jibberish.
.

I am having problems understanding where your misunderstanding lies.


Quote:
Maybe I'm wrong but I believe you have this backwards. If the amplifier had its way, its output impedance wouldn't rise and all amplifiers would be happy little creatures with a simple life. Of course, that won't happen since an amplifier must drive a loudspeaker to do its work. Therefore, if we are discussing a "reasonably well designed and adequately built amplifier", I don't believe the problem is rising output impedance of the source but rather it is falling impedance and reactive nature of the load. One is the problem while the other is the symptom. But merely stating a low impedance load as you have done does not suggest the speaker load makes life difficult for an amplifier.

The amplifier has to cope with reactive loads,if it cannot the problem is with the amplifier.


Quote:
What do you consider "perfect"? An amplifier with the lowest output impedance in all cases? >That would make life simple when choosing an amplifier I suspect though it would certainly lead to a lowest output impedance race amongst designers. No more listening as dup suggests. "Just give me the facts, m'am, lowest output impedance or not. Either it is and I buy or it's not and I walk." Goodbye tube amps, goodbye demo rooms and goodbye Stereophile. Once a year JA just prints a product guide with nothing more than the output impedance of each amplifier.

See above.


Quote:
I think we can both agree a "typical" tube amplifier's output impedance is probably going to be >>higher than that of a direct coupled solid state amplifier.?

Not the same as the speaker impedance though. Do you know why tube amplifiers sound quite good?

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Re: amps VS. watts


Quote:
Your math works only for low impedance loads. This would make you correct if all loudspeakers were a consistent load - and all loudspeakers were low impedance loads. Since loudspeakers are not a consistent load, but are reactive as we've all agreed, your math only applies to certain frequencies at particular impedance loads. The ability of the amplifier with the lower output impedance to deliver more "power" into a 3 Ohm load is not relevant to what it can manage at all other frequencies which fall above 3 Ohms - which would be the majority of information contained in most music and where the speaker load tends to be more ideally resistive or rises to a significant degree


Quote:
I demonstrated in my previous post that with a tube amp, about 1/3 of the power is lost at certain frequencies into a 3ohm load. So it will still work.

99%? As far as how many that hit 3ohms are on the market? From (fig4) I

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Re: amps VS. watts


Quote:
The amplifier has to cope with reactive loads,if it cannot the problem is with the amplifier.

No, it doesn't have to. It need only cope with a highly reactive load if you pick a speaker with a highly reactive impedance and phase angle. Why buy such speakers when you don't have to and there are more than a sufficient number of decent sounding speakers that do not require amplifiers capable of arc welding?

I once again repeat, "Only when amplifiers are asked to perform Herculean tasks does either amperage or output impedance become relevant. Therefore, the real question I find myself asking would be; why are we expecting amplifiers to perform Herculean tasks?"

This way of thinking is in line with Jim Theil's belief that "watts is cheap". And his speakers require lots of watts.


Quote:
Do you know why tube amplifiers sound quite good?

Russ, I believe this is my stop and I really don't wish to get on that bus with you.

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Re: amps VS. watts

What I find completely amazing is that John Atkinson has the ability to read this thread and know better than to get involved. Must be difficult to refrain from trying to help out.

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Re: amps VS. watts

Why do you say that? What sort of help do you suppose he might provide? I've agreed that lower output impedance is of value when the amplifier is faced with a difficult load. I don't know why everyone keeps repeating this as if I'm objecting to that fact. I have not agreed that more power is the arbitter of good sound. I have stated an amplifier need not face a difficult load to produce good sound.

Can we all not agree that the more "amps" an amplifier produces is by itself no indicator of a better sounding system? That is the original question of the thread. How we got into this prolonged discussion of output impedance is a bit beyond me.

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Re: amps VS. watts

Jan, you sound a bit agitated. Of course we can agree that the amount of amps produced is not the measure of it's quality. We all know it's watts that determines quality.
Just messing with you.
What is there in life that can be quantified by just one quality? Amplifier watts, Camera mega pixels, TV resolution, vehicle HP, computer CPU speed? So many of todays products are marketed on just one specification without taking into account the integration of the complete system.

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Re: amps VS. watts


Quote:
99%? As far as how many that hit 3ohms are on the market? From (fig4) I
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Re: amps VS. watts


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Jan, you sound a bit agitated

I admit to being confounded as to why this has taken nine pages to get to this point.

CECE
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Re: amps VS. watts

WATTS is the starting point, if i know i want to have some realistic live sound, I don't even look at or consider a measly 100W or so pc. Watts matter. There is no hi fi without them. A better amplifeir with plenty of output devices, puts out lotsa current into any load, it really is that easy. And it can maintain teh voltage across the speaker in order for it to deliver teh current called for...then those 2 give ya WATTS, it matters. There is no hi fi, without watts, good clean, fast, stable, well heat sinked, so teh amp doesn't crap out. audio amplifier is a power supply, so the one with teh larger AC mains transformer is also the better ampliferi, sometimes simple electrical concepts are teh correct ones. Speed, current, low distortion, stabilty, and super freq response, mine run something like 10-500Khz freq response, it matters, just like super fast slew rates....the sound is not in teh finely crafted front panels with fancy engraved markings, or viewing windows to look at glowing tubes, that's all crap, and is a nice show, but when ya listen to the music, I ain't looking at teh front panels of teh amplifiers.....maybe if ya can't build great amps, just build nice covers for them, someone will buy em. Yeah, a window to view teh tubes, ain't that special, that's as dopey as the tube CD players with teh window to see a tube glowing, what an audiophile won't fall for.

cyclebrain
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Re: amps VS. watts

Well why didn't you say that in the first place?

The difference between and median is that median is the halfway point between the minimum and maximum. The mean is the average, which takes into account the duration of levels.

Jan Vigne
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Re: amps VS. watts

uh-huh, that's what I thought. But that doesn't indicate 70% dropped to 3 Ohms. Or have I misunderstood again? I just don't see 70% of the speakers dropping beneath 3 Ohms in that graph or the text indicating such a situation.

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Re: amps VS. watts


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What I find completely amazing is that John Atkinson has the ability to read this thread and know better than to get involved. Must be difficult to refrain from trying to help out.

I think that would be the case for any of those whom have gone through years of formal scientific training.

Science is a land of discovery -- there are no authorities in science - some people are open to learning from others and others have this notion they are a full authrority in something that (especially in the case of of Hi-Fi) requires many disciplines to come together to bring what they have learned forward - at the same time learn from the other disciplines in the field.

Some threads turn into "I can pee higher than you" contests and there is no need.

Quote.... "Science warns me to be careful how I adopt a view which jumps with my preconceptions, and to require stronger evidence for such belief than for one to which I was previously hostile. My business is to teach my aspirations to conform themselves to fact, not to try and make facts harmonize with my aspirations." T.H. Huxley

CECE
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Re: amps VS. watts

Wasn't the guys Watt and Ampere scientists, who said, this is how it is, after seeing Voltaire.....if these 3 dudes didn't stick to their ideas, we might be discussing the effects of not enough (what) watt?

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Re: amps VS. watts


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No, it doesn't have to. It need only cope with a highly reactive load if you pick a speaker with a highly reactive impedance and phase angle. Why buy such speakers when you don't have to and there are more than a sufficient number of decent sounding speakers that do not require amplifiers capable of arc welding?

Arc welding is an exaggeration and a big one.


Quote:
I once again repeat, "Only when amplifiers are asked to perform Herculean tasks does either amperage or output impedance become relevant. Therefore, the real question I find myself asking would be; why are we expecting amplifiers to perform Herculean tasks?"

You make designing an amplifier to cope with a complex load sound as difficult as a moon shot, it isn

Jan Vigne
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Re: amps VS. watts


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Arc welding is an exaggeration and a big one.

You apparently have not been around this hobby for long. Dig up some reviews of the original Apogee Scintilla and read about the amplifiers used with that beast. Or the Infinity's of the same time period. There was a time when audiophiles did some very stupid things. (That should get a response!) And it seems speaker designers never talk to amplifier designers and vice versa.


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You make designing an amplifier to cope with a complex load sound as difficult as a moon shot, it isn
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Re: amps VS. watts


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Arc welding is an exaggeration and a big one.

Monotech - from the UK -- could deliver enough to weld steel - we tested them in 1989 - my god, they were well made. - Great as PA amplifiers with a relaibility NASA could only dream of. We deployed a lot of these into Mediteranean and Saudi climates (Hotels - Night clubs - Rock venues) and non failed.

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Re: amps VS. watts

It's not audiophile if it doesn't have limits, persnickerty faults, incapable of being reliable, drive anything it's hooked to. Be super reliable, and sound great. With SPECS that prove it's superiority. And have most of it's price inside, in components, and LARGE AC main transformer....not in some chassis that costs more than the parts inside. And never let it be able to be used in a commercial enviorment, with super reliablity, that somehow makes it non hi fi super grade audiophile. Again, since an amplifier is a modulated power supply, it has to deliver power, with is current and voltages at any load, that's the sign of a great design. If you "tweak" some gear with a magic connector, and all of a sudden the sound is more spacious, open, detailed, it either had poor connections,corroded bad solder joints, or you had too much vodka. High end sound, isn't mystical, just great electrical design and packaged in a proper case. Why do i want to look inside an etched glass window at some tubes glowing? How is that high end SOUND? That's stuff for Better Homes and Gardens, Or house Beautiful. Back to the SOUND, Back to electrical electronic design. Years ago SoundCraftsmen made amplifeirs that would be tested into direct shorts, several times, to prove it's superior ckts, they would shut down, then resume operation, with no damage. They didn't cost ten$ of thou$and$ of dollars either, they delivered several hundred watts into any load you hooked it to. so much great stuff available, and also so much hyped nonsense, are StereoPhile readers buying art work, or sound? I think it's drifted into buying art, not audio.

Jan Vigne
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Re: amps VS. watts

Was there not a manufacturer who demonstrated the stoutness of their high end power amplifier by running it into a dead short? I seem to remember the light show from the demonstration being the talk of a C.E.S. Not exactly arc welding but not far from it.

Jan Vigne
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Re: amps VS. watts

Seems the demonstartion I was referring to has been more recent than Soundcraftsman days.

Where did Soundcraftsman end up after its brief but unpromising engagement in high end audio? Pro sound. And not for its arc welding capabilites. It was never a top notch consumer amplifier, it just held together better than a Phase Linear - which ain't saying much. This is kinda like designing a car that can withstand a 50 M.P.H. crash rather than designing a car that can avoid a 50 m.p.h. collision.


Quote:
Again, since an amplifier is a modulated power supply, it has to deliver power, with is current and voltages at any load, that's the sign of a great design.

Speaking of such, dup, do you work a second job as a crash test dummy? Sounds like the sort of thing you'd enjoy.

Jan Vigne
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Re: amps VS. watts


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And never let it be able to be used in a commercial enviorment, with super reliablity ...

http://cgi.ebay.com/SOUNDCRAFTSMEN-RA-75...1QQcmdZViewItem

Unfortunately, it's not working today. Guess that dead short demonstration finally caught up with them.

wkhanna
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Re: amps VS. watts

Oh what a blast from the past!

Proof that SoundCraftsman did for a short time exist in the HiFi realm.
My old SC pre-receiver, now in need of a CraigsList posting along with some V nice (NOT)

CECE
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Re: amps VS. watts

yupper, when those 30 year old amplifers give up, it's a sure sign they musta been no good. Too bad my friend has one and teh pre amp equalizer and tehy both function flawlessly, the one that was the littel cube BEFORE Carver decided to take the idea and market it, it had a triac control, the thing was small, could put out like 200 hundred watts p/c down to.....under 2 ohms, again, well made, delivers the current needed, a stack of em could deliver some power, 200W per channel in a box less than 12 inches by 12 inches, no fancy chassis, it just worked well....not enough power for my needs though, but certainly better than some 35W.

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Re: amps VS. watts


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Oh what a blast from the past!


I like the "liquid cooled" stickers on the speakers. It's true, but it would have never occurred to me to market them this way.

CECE
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Re: amps VS. watts

Multi way speakers are the way to go. No single driver is capable of doing it all, impossible, unless you are talking bout' a clock radio, or carradio, not realistic reproduction. Active crossovers for residential use is unnecessary. Active crossovers are used in large commercial enviorments, when multiple speakers are placed about a large area, where drastic room response differences are encountered. And the only way to get it together is to tune each cabinet to the room response with electronics. Checkout some large pro installations.

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