The thing about amplifiers and such, is that someone who is 'well versed in the art' of distinguishing different setups will have much recorded material which makes such a task trivial to perform; for them it is a nonsense when people declare that it is "all in their head", or some such throwaway..
The key thing is, that I have looked at some of the experiments as performed by these people, where I do have access to the details, and to me they have so many shortcomings I can't take them seriously as "proving" some of the ideas expressed in the attitudes repeatedly shown in this forum.
But it is real (at least to me). And I'm looking for possible explanations for that. Not the other way round.
Sy: during my holidays, I can spend 20 hours in a row listening to music on my system, sometimes with some experimenting for instance with different diaphragms on the compression drivers or with different drivers. I have a few thousands records at my disposal. I am able to do by ear a pretty decent sounding passive crossover for a loudspeaker.
I'm not alone. We are a quite a few freako-monsters like that out there.
Believe me, we can make a difference between the sound of two amps, provided they sound differently of course.
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Lets try and collect the evidence so far.
The crown is a well designed and respected power house that will run flat out all day in a PA rig. What measurements there are appear pretty blameless.
You have very high sensitivity speakers that only need a few watts to drive to above safe levels (unless you live in a warehouse).
You think there is something special (slam) about the crown.
A number of people agree with you, but most appear to work or have worked in sound reinforcement.
There is no consensus on what 'slam' is or the part of the audio spectrum it lives in.
In tests you have perceived the crown to sound very different from other amplifier (which all sound similar)
Humans are known to be very susceptible to suggestion.
You have been told by people that Crown amps have 'slam'
you are really happy with your Amp/speaker combo
No one has come up with a credible technical reason for why the crown amp would be superior at such lower power levels.
Can anything be concluded from this? Well to me the following options come to mind
1. It might be the huge damping factor, but it is easy to reduce that in a test
2. you might have a ridiculously horrible reactance somewhere that needs an amp capable of ark welding. This should be measurable.
3. you believe your amp has slam so it does.
4. There is some distortion at very low output levels that is pleasing to your ear.
Whichever is correct it doesn't actually matter as you are a happy camper. I meanwhile am jealous cos I don't have a welding amp.
Which, obviously your reading thereof is rather challenged?
Go ahead, try to buy something from me. Although I would rather be "in the game", I'm not at the moment, and have not been for some time. I have nothing to sell.
You ought to apologize.
You who oft demands facts, measurements and the like is throwing a lot of mud in this thread.
Frankly, cut it out.
Talking of amplifiers, and systems that will have the ability to do "slam and impact", this mob seem to have a good handle on things, http://www.cinepro.com/Specsheets/Mk5-SeGoldCellSheet300DPI.pdf and http://www.cinepro.com/reviews/HomeTheaterMagazineHES2007Review.pdf
You can stick your fingers in your ears and still tell the difference between some amplifiers.
I actually demonstrated this with two different CD players, one had 'slam' and the other did not.
Two different amplifiers that had real 'slam' would make the dust-caps of a pair of B&W DM3000's cave-in on bass notes (and make them sound distorted).
One of the above mentioned amplifiers had a DF of only 14, one of the amplifiers with no 'slam' had a DF of 400.
The amplifier with the DF of 14 sounded 'warm and fuzzy' until it had some bypass caps installed. After the bypass caps were installed it had 'slam' in spades, and HF detail too.
I actually demonstrated this with two different CD players, one had 'slam' and the other did not.
Two different amplifiers that had real 'slam' would make the dust-caps of a pair of B&W DM3000's cave-in on bass notes (and make them sound distorted).
One of the above mentioned amplifiers had a DF of only 14, one of the amplifiers with no 'slam' had a DF of 400.
The amplifier with the DF of 14 sounded 'warm and fuzzy' until it had some bypass caps installed. After the bypass caps were installed it had 'slam' in spades, and HF detail too.
The results of this research has been replicated over and over, but your not even willing to read it...
You seem to know better than the scientists, if this is true you must have no difficulty to provide some peer reviewed research.
Btw you haven't put up any real criticisms for the vast amount of research done in this field.
The "cold fusion" results have actually been replicated. But there's no full theoretical explanation to push research further. People are working on it though. https://en.wikipedia.org/wiki/Cold_fusion
SY has put up lists of lots of research papers here, use the search function. Your acting like an ostrich with his head in the sand. That doesn't make the research go away.
The only commercial amp I currently use is a pair of mono Sunfires running the subwoofers; I got these from a "yard sale" at NHT a few years ago, where they were built in to one of their flagship speakers. No Crown Macros or Studios, but if I were given one, I'd gladly take it- it would be a fun thing to have in order to annoy the neighbors via increased SPL.
I'm not sure of the relevance of this to the topic.
I'm not sure of the relevance of this to the topic.
Again the old audiophile debating gambit, anyone who disagrees with the audiophile manifesto must have cloth ears or be incapable of designing an experiment.
I am not claiming that all audio amps sound the same, and I don't think anyone claims that. I'm claiming that all audio amps whose measured performance is above a certain level sound the same.
I am not too sure what that level is, but all published work I've read that used blind testing techniques points to it being rather low. I don't know where the Crown we are debating about stands in relation to the level. The performance figures in the datasheet aren't really helpful as they show the amp in its best light for prospective buyers, but we want to know about its weaknesses. If I were investigating this, I would make THD plots of it at 10kHz and several power levels around 1W.
It is also not trivial to show that the amp is actually giving the same performance that you measured in the lab, when it's connected to real speakers and driven with music. Valve amps are famous for playing tricks in this respect, as they change their frequency response according to the load. But a big "arc welder" of an amp should hardly care about the load.
I think these are valid topics for debate.
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I saw those measurements, they forgot to measure THD at high frequency and low power, the very thing that I am most interested in. Need to know how well the V8 can balance the Segway.
See figure 4:
Crown Macro Reference power amplifier Measurements | Stereophile.com
1 watt and up to 50kHz.
Whoops, I missed the "2.83V" there. Anyway, those results do suggest a fair bit of crossover distortion at low levels, especially since they seem to have been done with an 80kHz measurement bandwidth that would filter out the worst of it. The difference in distortion between channels also points to a crossover issue, as even a slight difference in bias between channels would account for it.
0.03% at 10kHz and 1W is really not "Blameless" and would set Douglas Self off on a rant. And how do we know that it doesn't get a lot worse, maybe while the amp is warming up?
0.03% at 10kHz and 1W is really not "Blameless" and would set Douglas Self off on a rant. And how do we know that it doesn't get a lot worse, maybe while the amp is warming up?
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my point of view for answer to 1 page Q:
for earlier models
1. power transformers was from good cores and Cu, properly winding.
2. they used industrial paired "special order" output transistors, from very good quality.
3. other parts like Capacitors also was much better...
4. used solder was much better (multicore example, shining for 30years...)
for earlier models
1. power transformers was from good cores and Cu, properly winding.
2. they used industrial paired "special order" output transistors, from very good quality.
3. other parts like Capacitors also was much better...
4. used solder was much better (multicore example, shining for 30years...)
You are claiming about something you aren't sure, Scopeboy! (Of course that is SAFE for you)
Everybody knows that above certain level (whatever that is) amplifier sound differences cannot be heard. If you cannot give your numbers (i.e the level) why debate others with their own "level"?
If the subjectivists are supposed to have the burden of proof, the objectivists should also have the burden to specify the threshold numbers, then later may be we can arrange a proper blind test. If you were deaf, you could not assume that everyone else is deaf also. Because people have different ears and hearing skill/experience, and that is a FACT.
It depends on (the ears of) the participants my dear. It is not even touching the critical issue that we should find out...
IF YOU cannot hear the difference between amplifier A and amplifier B in a blind test, will do you think you have the same level of enjoyment listening to amplifier A for one month and listening to amplifier B for one month?? (think and answer it)
Crossover distortion of class B amplifiers, is probably one reason why listening to class-A amplifier for hours tends to give less fatigue. And fatigue is not something you can perceive in a short time like in a blind test.
The numbers.
That's why the scientists in the field select people with good hearing and train participants to hear the differences they want to test.
Selection and training...
If you can't hear a difference, you can't hear a difference.
2 strawman arguments:
Class B amps are a thing of several decades ago and so is crossover distortion.
Blind tests are not limited in time.
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