Well, if you don't fill your time in by being in a drunken stupor, there are other entertainments . . .
Article over here in the press about the English and Scots being the worst drunks (defined as slurred speech and staggering gait) out of 25 nations surveyed.
Apparently most folk feel some embarrassment the following day, but not in Britain. A badge of honour apparently.
Article over here in the press about the English and Scots being the worst drunks (defined as slurred speech and staggering gait) out of 25 nations surveyed.
Apparently most folk feel some embarrassment the following day, but not in Britain. A badge of honour apparently.
Some say that all amplifiers still sound the same and if they do sound different, then they are faulty.
I used to know people who believed in double-blind listening and now don't. These are people who actually conducted them. Me too. Then it dropped that they were testing the capability of the listener and not the equipment. Music is meant to put you at ease and be a calming influence. You were now using music as a weaponised tool and now you were stressing the subject. The subject was not whether the amplifiers sounded different, but whether a listener put into stress could tell the difference?
This does not mean that I dismiss DBL tests entirely.
Re the sound of tubes, to varying degrees and depending on design, they do sound different, to each other and to most solid-state. I believe (and hope in the future to supply measurements) that the output transformer into dynamic loudspeakers has an advantage and that this lowers distortion on the current side of the amplifier. In a conventional driver, only 30% of the voltage is inside the magnetic gap (often a LOT less than that) in an overhung voice coil. But always 100% of the current goes through the entire voice coil and that includes 100% of the current goes through the gap. We are listening the current of the amplifier and not its voltage. Yet very few (some have) measure this current distortion, but when they do, the distortion is much higher than the voltage of the amplifier. I repeat: We don't really listen to the voltage of the amplifier, but we always listen to the 100% of the current of the amplifier. Chew on that!
Edit/PS: And then bring in crossovers and the situation gets very complicated. We should design crossovers as current dividers and not as voltage dividers. When you do, the sound becomes more accessible or just plain more engaging.
I used to know people who believed in double-blind listening and now don't. These are people who actually conducted them. Me too. Then it dropped that they were testing the capability of the listener and not the equipment. Music is meant to put you at ease and be a calming influence. You were now using music as a weaponised tool and now you were stressing the subject. The subject was not whether the amplifiers sounded different, but whether a listener put into stress could tell the difference?
This does not mean that I dismiss DBL tests entirely.
Re the sound of tubes, to varying degrees and depending on design, they do sound different, to each other and to most solid-state. I believe (and hope in the future to supply measurements) that the output transformer into dynamic loudspeakers has an advantage and that this lowers distortion on the current side of the amplifier. In a conventional driver, only 30% of the voltage is inside the magnetic gap (often a LOT less than that) in an overhung voice coil. But always 100% of the current goes through the entire voice coil and that includes 100% of the current goes through the gap. We are listening the current of the amplifier and not its voltage. Yet very few (some have) measure this current distortion, but when they do, the distortion is much higher than the voltage of the amplifier. I repeat: We don't really listen to the voltage of the amplifier, but we always listen to the 100% of the current of the amplifier. Chew on that!
Edit/PS: And then bring in crossovers and the situation gets very complicated. We should design crossovers as current dividers and not as voltage dividers. When you do, the sound becomes more accessible or just plain more engaging.
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Can you quote them or post links?
This is about replaying music. There is a difference.
I thought people can only listen to sound waves. How do you listen to current of the amplifier? Does it involve some kind of probe into our body?
Man Walks into a Pub: A Sociable History of Beer (Fully Updated Second Edition): Amazon.co.uk: Brown, Pete: 9780330412209: Books
According to this book (which is a great light read) Britains have been the rowdy drunks of Europe for many hundreds of years. It's bred into our DNA now.
Thank goodness you don't have to test beer with leather trousers any more...
I thought people can only listen to sound waves. How do you listen to current of the amplifier? Does it involve some kind of probe into our body?
That's not an intelligent reply. We either listen to the voltage of the amplifier (note the subject is the amplifier) or the current of the amplifier. Maybe you listen to the input to the amplifier? Then why do you have an amplifier? Why do you have speakers? Sorry, but you gave a silly answer and deserved an equally silly answer back.
So this opens a demarcation problem. Do you mean that you only dismiss DBL tests when the outcome doesn't suit your purposes? Or that proof is only good when it proves your point?
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It's almost comforting to know that, despite whatever else is going on in the world, you can count on the Blowtorch / Black Hole thread to continually repeat itself.
Interesting. You start a post with citing of your imaginary event "Some say" and then call my reply silly.That's not an intelligent reply. We either listen to the voltage of the amplifier (note the subject is the amplifier) or the current of the amplifier. Maybe you listen to the input to the amplifier? Then why do you have an amplifier? Why do you have speakers? Sorry, but you gave a silly answer and deserved an equally silly answer back.
Perhaps you do but not me Joe, I listen to the sound the speakers make. You are well known for your speaker design and should be aware of the tools to measure distortion of the sound. No need to again go through useless roundabout on voltage or current distortion in confusing manner.
Ahhh... the Aussie Dane... I still have a Danish (Dansk) passport.
I see that I brought out the 'usual suspects' and my calm leads to their heat.
We can measure the distortion of the current and it looks like this:
Current drive of speakers and speaker distortion
I don't think that Pavel realised that both the measurements on that page, proved that his amplifier had two simultaneous distortion profiles. Yep, at the same time.
This is the voltage of the amplifier:
voltage (of the amplifier)
Using a current sense resistor.
current (of the amplifier)
Note his mistake, it is a beauty and I tried to point it out to him:
He says "speaker current" - but the speaker is not the source of the current.
The amplifier is producing that distortion!
Only when the load is purely resistive do the two distortion profiles become the same. But the driver bosses the current of the amplifier because it can only control the voltage (voltage source).
Note Pavel used a voltage source amplifier for the above measurements.
Another mistake: The driver produces less distortion under current drive. Wrong!
What really happens is that the amplifier responds and emphasises in a loop the distortion of the driver. Esa Merilainen calls this "feedback" in his book. I know what he means, but basically the amplifier's current becomes smeared and IMD measurements shows this up even more.
Finally, he used 1R current sense resistor. If he had used 0.1R value, the current distortion measurement would have been even more dramatic, and it is already dramatic.
What does it prove?
We listen to the current of the amplifier, not its voltage.
Typically only 30% of the voltage of the amplifier appears inside the magnetic gap when we use overhung drivers. But 100% of the current always appears inside the magnetic gap and that is what we listen to.
A voltage source only produces a potential for current, not actual current.
Did you mean to say we listen to the effects of the current of the amplifier?
Perhaps sales is down with his business.
Hi Indrawan
Please, the whole situation has been long confused before I even came on to the scene. Yes, I have designed a number of loudspeakers, I keep an eye on what the current does. It works!
This is about getting things right and getting rid of the confusion and often outright folklore. If we know how the current of the amplifier behaves, then we can absolutely find techniques that will improve speakers, improve crossovers and indeed improve amplifiers.
Please read my previous post. In dynamic drivers with an overhung voice coil kind, about 30% of the voltage appears inside the magnetic gap; that's 30% of the voltage of the amplifier. But 100% of the current always appears inside the gap.
As for replying to others here, go jump!
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