Andre Visser said:
Well, since you never get any further than this statement, we'll never know don't we?
I think we can agree that any sound difference must come from a signal difference at the speaker terminals.
We may also agree that we can measure much more sensitive than we hear. For example, I can measure response differences down to 0.01dB. I can measure non-linearity differences down to -120dB. I can measure phase differences down to a fraction of a degree.
We can measure under circumstances that are very close to music reproduction, and with speaker-type loads.
Why can't I measure the differences you claim to hear? What should I measure then? Help me.
Jan Didden
janneman said:
Jan, if I knew how, I would not have made such a statement.
janneman said:
Perhaps you can rather help me. 😀
A few examples: I've made relative small changes to an amplifier that changed the bass from loose 'undefined' (may sound louder) to tight punchy bass without making any difference to the FR measurements. Some equipment reproduce low level detail and ambiance much better than other, how do you measure that? Also the old one, how to measure soundstage focus? What measurement will show whether your foot is going to tap with the music? 😀
Dear Moderators,
may I respectfully propose that this thread is now transferred to the 'Everything else' thread since we stopped having sensibe, open minded discussions about 400 pages back.
may I respectfully propose that this thread is now transferred to the 'Everything else' thread since we stopped having sensibe, open minded discussions about 400 pages back.
Andre Visser said:
Good, hard questions. I don't have ready answers. Some ideas:
To start backwards: I don't think that the difference between two well-engineered amps is that one will make you foot-tap, and the other not. Foot-tapping is about emotion and 'rapport' with the music and you don't need top-of-the-line equipment for it.
To measure differences in sound stage width, ambiance, I would look at crosstalk over the audio-band at various levels. Low level detail should be related to dynamic range, that's an easy one.
But first and foremost, we need to establish that the differences heard (or perceived) are only the sound differences. That's the basis, it doesn't make sense to chase some subtle difference unless we're pretty sure there is one.
So, knowing how unreliable our perceptive apparatus is in these things, how do we make pretty sure that there is a sound (only) difference.
Jan Didden
Dear Jan is clear that your approach and absolutely correct, to build an amplifier's' need a good engineer like' of electronics, what else is not 'math. Then once all the appropriate measures.
but I believe that this is only half the job, and that we understand very well from what John says, if you notice about the blowtourch always relate to ctc like a team, where Crump has cured the choice of components and l' other layout
I think john is very modest when he says that they are not experienced in these last two areas ...
I have certainly not as I tell you that in real life all component do not work as its simplified circuit, and in the end the mix of components like' their non-linearity 'distortions and has a certain weight on the final result, as the layout
like how fabulous cake grandmother is, despite you know the recipe is not so 'good....😀
but I believe that this is only half the job, and that we understand very well from what John says, if you notice about the blowtourch always relate to ctc like a team, where Crump has cured the choice of components and l' other layout
I think john is very modest when he says that they are not experienced in these last two areas ...
I have certainly not as I tell you that in real life all component do not work as its simplified circuit, and in the end the mix of components like' their non-linearity 'distortions and has a certain weight on the final result, as the layout
like how fabulous cake grandmother is, despite you know the recipe is not so 'good....😀
janneman said:
Perhaps "well-engineered" must be defined first. 😀 I've listened to a lot of 'high-end' amplifiers that will not make my foot tap even after 10 beers.
It is possible to influence soundstage size with changes inside monoblock amps, I would think that crosstalk would not be a factor in this case.
Regarding low level detail, I've heard amps that can't even keep up with the HF while complex bass notes are played, let alone detail. I believe something much better than a single test tone will be needed to measure this.
The first obstacle would be to figure out how we perceive sound, there isn't much logic in pushing for certain good measurements far beyond what we can hear but ignore other things that are important to the way we hear.
I believe once we can figure out how to measure in a way that correspond to the way our ears / brain function, there will be much less claims that our "perceptive apparatus" are unreliable. Different yes.
At the speaker terminals connected to a speaker, since the speaker's impedance varies with frequency.
This poses a major difficulty, since different speakers behave differently.
The major question is what we measure and how we measure it.. Here KBK raised good and valid points in posts numbers 12440, 12442 and 12455.
janneman said:
However, audio gear is aimed at that very "unreliable our perceptive apparatus".
It's not only possible, it actually happens.
After choosing loudspeakers few months ago, I tested various amplifiers to go along those speakers. One amplifier I tested was 2 high power high current high end monoblocks. They had a lousy sound stage.
Agreed.
Crosstalk is often blamed to be responsible for soundstage space creation, but it is a complete nonsense and a mistake of those people who are not doing comparative tests. The monoblock amps are a perfect example.
PMA said:
OK, so let's be a little illogical and not very rational, and just for the sake of discussion assume that the monoblock example is valid.
Pavel, what type of measurements then might shed some light on soundstage creation? Could it be related to power supply interaction? If one would want to express sound stage width in terms of electrical signal properties, what would they be?
Has anybody here some info on that?
Jan Didden
An old-fashioned two tone intermod test will show this, assuming it's a problem with the amp. I hear this a lot with full-range speakers, not so often with amps (other than very cheap ones with weedy power supplies) that aren't being run into overload.
SY said:
SY, the problem was with the amp, it disappeared with another amp. I have my theories about that problem but let us leave that one alone. This example was extreme, my main concern is with detail that get lost and how to see that in measurements.
The do a simple IM test. 60 and 6000 Hz should show up any electronic problem. Nothing mysterious about it.
How did you verify that the first amp wasn't being run into overload? Did you have a scope on the output while you were listening? How did you verify that the listening tests were conducted at the same SPL? Did you have an SPL meter or calibrated spectrum analyzer running during the listening sessions?
If you're seriously interested in correlating measurements to audible phenomena, it's not a terribly hard thing, nor does it require very exotic gear.
How did you verify that the first amp wasn't being run into overload? Did you have a scope on the output while you were listening? How did you verify that the listening tests were conducted at the same SPL? Did you have an SPL meter or calibrated spectrum analyzer running during the listening sessions?
If you're seriously interested in correlating measurements to audible phenomena, it's not a terribly hard thing, nor does it require very exotic gear.
Yes. Give me two amps and a multimeter and I'll tell you which one sounds the most spacious in a specific system, that isn't changed between swaps.
Jan Didden
Jan Didden
Research
Today I have payed for a month access to free service manuals, it's just
US$5 and there a lots of nice schematics and service manuals, a lot of japanese vintage audio products but even rather new designs.
It is very interesting to see that their intentions to design a decent phono stage has decreased from very sofisticated designs with JFET and servos to very simple cicuits with just one IC, like all in one solution.
It is also very interesting to se what others has done, BTW I was on the Ebay there is a guy called JIMS he has a lot of kits I don't really now if it good stuff or not.
It would be nice if someone here has tried JIMS products and could tell something about this firm and products.
PS.
I also will tell you that it is a sort of anniversary as this is the page 500.
DS.
Kamskoma
Today I have payed for a month access to free service manuals, it's just
US$5 and there a lots of nice schematics and service manuals, a lot of japanese vintage audio products but even rather new designs.
It is very interesting to see that their intentions to design a decent phono stage has decreased from very sofisticated designs with JFET and servos to very simple cicuits with just one IC, like all in one solution.
It is also very interesting to se what others has done, BTW I was on the Ebay there is a guy called JIMS he has a lot of kits I don't really now if it good stuff or not.
It would be nice if someone here has tried JIMS products and could tell something about this firm and products.
PS.
I also will tell you that it is a sort of anniversary as this is the page 500.
DS.
Kamskoma
- Status
- Not open for further replies.