Just read a review of the Eeyore Anya system in a local pro audio mag....by the description, very impressive.
105 dBA in all spots ought to be seriously impressive too....on AC/DC hell yeah, but not those yank sports announcers, they would drive me out of the stadium quick smart
.
Dan.
BTW, have you tried any of those mud/orange/etc experiment recordings over one of your PA's ?.
I have a tweak that changes live Pa's very interestingly....I also have a recording of a Devo show that captures the difference.
105 dBA in all spots ought to be seriously impressive too....on AC/DC hell yeah, but not those yank sports announcers, they would drive me out of the stadium quick smart
.Dan.
BTW, have you tried any of those mud/orange/etc experiment recordings over one of your PA's ?.
I have a tweak that changes live Pa's very interestingly....I also have a recording of a Devo show that captures the difference.
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I knew you had some good reasons to suggest voltage sensitivity.
But the need is catering for the un knowledgeable (public).
The knowledgeable (professionals) were aware of the possible pitfalls or miss practices, as they can always be.
With the voltage sensitivity spec bombardment through the brochures, minute after minute we are dragged away from the real meaning of this spec which was a certain sound dB level output–say 90dB-measured at 1m from an 8 Ohm speaker fed with 2.83Vrms. That was 1 Watt electric power (P=V*V/R) supplied by the amp.
If the bloody speaker now is spec’d as 90dB/2.83V/1m but it is 4 Ohms across most of the bass-mid range, it will suck 2 Watts from the amplifier to achieve this sound level.
So the new spec managed to take the onus of honest compliance to a clear efficiency spec from the backs of the manufacturers and placed the consequencies of the voltage sensitivity spec on the shoulders of the un knowledgeable consumer (running for more powerful amplifiers).
Take it for granted that today a consumer reads only the dB number on the voltage sensitivity and judges speaker's efficiency by it.
I smell fire (check this on paper )
The fact that an amp will provide varying current according to driver/loudspeaker impedance is not of great concern typically.
It should be, see a few lines above
George
I concur.
Well put. Thanks.
Definitely..
That is not teaching. I've seen teaching before, what is being done is not that.
You're telling Sy to stop playing games?
Bummer, I was hoping to learn that stuff..
Actually, he's been straightforward. You've not been straightforward, but certainly consistent.
Hmmm..very carefully?
I'd try, but it would probably take me forever..
jn
Dan, because it typically advertized as an expression of efficiency, the unit in should be Watts, not Volts.
The fact that for PA a measure of SPL vs. V might come in handy is a separate issue, which I am happy to accept from you as being the case.
On the other hand, loudspeaker efficiency combined with power handling (also in Watts!) is essential to determine how loud you can play/ how many loudspeakers you need for a certain location. So that would argue the opposite point, also from the PA perspective.
Anyways, my point is that for PA=professional use, it is easy to do the conversion when needed, but why mess around with a basic concept like 'efficiency' and express it using the wrong dimension.
Exactly the same algorithm as described here:
IEEE Xplore Abstract - Reconstruction of High Impulse Voltages Considering the Step Response of the Measuring System
Jan, Pavel, et al,
So thinking about how we list speaker output and efficiency how should we really show a true or reasonable value? What I am thinking is that with most speakers you have a rising rate impedance curve most often and will also have a minimum value somewhere across the band. So how accurate is it to just show the value at the minimum impedance or at a set 8 ohm or 4 ohm value when that is seldom the case? For a speaker you could give a maximum voltage handling spec I suppose or a max current reading but that also doesn't show a good efficiency rating but at least would give you a safe power handling value. It seems we are attempting to give a single value to a device with a sliding scale requirement across the useable frequency response range.
As far as teaching goes, it seems with ES's method we are playing the Three Stooges game of Who Is On First. First you have to guess what the subject matter is and what it relates to and then when you answer who is on first the question changes to who was playing short stop! I don't find that method of relaying information very useful or even possible to follow. Please state what you wish to talk about clearly and then make your case for that case so that a real conversation or questions can be asked. To say that nobody is watching or wants a straight question and answer session while learning or teaching shows that there is an agenda or obfuscation involved.
So thinking about how we list speaker output and efficiency how should we really show a true or reasonable value? What I am thinking is that with most speakers you have a rising rate impedance curve most often and will also have a minimum value somewhere across the band. So how accurate is it to just show the value at the minimum impedance or at a set 8 ohm or 4 ohm value when that is seldom the case? For a speaker you could give a maximum voltage handling spec I suppose or a max current reading but that also doesn't show a good efficiency rating but at least would give you a safe power handling value. It seems we are attempting to give a single value to a device with a sliding scale requirement across the useable frequency response range.
As far as teaching goes, it seems with ES's method we are playing the Three Stooges game of Who Is On First. First you have to guess what the subject matter is and what it relates to and then when you answer who is on first the question changes to who was playing short stop! I don't find that method of relaying information very useful or even possible to follow. Please state what you wish to talk about clearly and then make your case for that case so that a real conversation or questions can be asked. To say that nobody is watching or wants a straight question and answer session while learning or teaching shows that there is an agenda or obfuscation involved.
Pink noise, IMO, with a standardized average voltage. It would be nice to report average current as part of the spec, but getting beyond a single number might be a commercial challenge.
Abbott and Costello, not the Holy Trinity.
Why is this relevant? Notice the gold leafs repel while the capacitor plates always attract.
Why do you still act like presenting common knowledge that contradicts something stated as a personal attack? You said, if I recall correctly, "Hint, It ain't drift velocity", well sorry it is and there are no signal charges that remain distinct from background charge.
It's hard to interpret things in the first place when they are presented with misdirection and ambiguity. Please don't call it my krap.
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I find conversing with Ed Simon fascinating. Certainly better than being told what I am told here by my critics. I must agree that he gets me to 'think' about basic processes in different ways, and sometimes I have to ask him a few supporting questions to understand what he is getting at. I recommend that those of you who would discount him should follow my example. You actually might learn something from another perspective.
John,
As far as I can see, you are pretty much one of the few who does not listen to the perspectives of others, especially when it comes to scientific knowledge you do not understand.
I see quite a few very technically strong people here trying to explain things to you, but you ignore them all.
So before you go about tossing all kinds of accusations about, do a self examination first.
Who knows, you might actually learn something from another perspective.
jn
Good one..
I on the other hand, listen to everybody. Even you..
jn
ps..man, I wish I were winding coils now, it would break the monotony.
Disallowed generalisation to move the goalposts to your corner.
Who says all ICs sound not as good as they measure? Do they actually? And which ICs sound better than they measure? Which discrete phonos sound worse than they measure?
I know - questions, questions...
Jan
I knew you had some good reasons to suggest voltage sensitivity.
But the need is catering for the un knowledgeable (public).
The knowledgeable (professionals) were aware of the possible pitfalls or miss practices, as they can always be.
With the voltage sensitivity spec bombardment through the brochures, minute after minute we are dragged away from the real meaning of this spec which was a certain sound dB level output–say 90dB-measured at 1m from an 8 Ohm speaker fed with 2.83Vrms. That was 1 Watt electric power (P=V*V/R) supplied by the amp.
If the bloody speaker now is spec’d as 90dB/2.83V/1m but it is 4 Ohms across most of the bass-mid range, it will suck 2 Watts from the amplifier to achieve this sound level.
So the new spec managed to take the onus of honest compliance to a clear efficiency spec from the backs of the manufacturers and placed the consequencies of the voltage sensitivity spec on the shoulders of the un knowledgeable consumer (running for more powerful amplifiers).
Take it for granted that today a consumer reads only the dB number on the voltage sensitivity and judges speaker's efficiency by it.
I smell fire (check this on paper )
The fact that an amp will provide varying current according to driver/loudspeaker impedance is not of great concern typically.
It should be, see a few lines above
George
George
The real problem is power amplifier ratings. If a loudspeaker is rated as eight ohms that means it will dip to four ohms and can go much higher. Now even if the amplifier is rated for four ohm operation the power output at four ohms is not double the power at eight. (Caused by the internal impedance of the power supply mostly.) So there will be frequency response variations that become level dependent.
Then there is the actual efficiency issue. The output at 2.83 volts input will not increase by 20 db at 28.3 volts input for most loudspeakers! For most of the transducers inside the box the impedance will double in use with out damage. So as you place a bit of power into the complete system the FR will also change due to driver changes.
Part of the power test standard is to raise the power level until a loudspeaker is 3 db down from the linear results expected. So there are actually two tests for power, as a transducer is tested to withstand rated power (as measured by input voltage) for two hours. Half will fail before four hours. (The old number was 100 hours, but marketing...)
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Disallowed generalisation to move the goalposts to your corner.
Who says all ICs sound not as good as they measure? Do they actually? And which ICs sound better than they measure? Which discrete phonos sound worse than they measure?
I know - questions, questions...
Jan
Jan,
My observations and those of others find that the race for lower and lower THD distortion does not track with improved sound quality. There are other issues such as noise pickup that degrade performance in real world applications.
For example the LME4560 sounds quite poor in an EMI noisy environment. An old fashioned TL070 works better in that case. It has higher noise and distortion, but in the final product it can produce better results. (Actual case study! Of course with a metal cased product and input filters the result would have been different, but on the bench the LME was clearly better and the field fix was to change chips. Now you and I know better and that experience added one more to the club.)
Now If you ask about phono preamps, back in the 70's There was a German manufacturer who instead of using the BOG standard two transistor phono preamp added a third buffer transistor. Measured better, virtually every one made was returned. Sounded horrible. (Was it that it didn't meet expectations or that records were mastered to be played back on the BOG unit, don't know. It did sound so bad the one I played with, I thought was broken, but all the measurements were right.)
But the issue was and is has JC done anything new, and my opinion is that his testing of loading effects is helping to show differences between IC based solutions and discrete. The ultimate test is of course after an issue is found, everyone says it is so simple that you always knew it!
Please let me know which statement(s) you disagree with:
Bob Cordell is a more than competent audio designer.
He did a phono preamp design that you published.
The design used an IC for the first gain stage for the moving magnet input.
The gain was set for 40 db.
If the gain were set for 20 db his feedback resistor would provide a greater load on the IC amplifier than rated.
George has provided his estimate that a MM cartridge can actually produce as much as .880 Volts peak.
Bob Cordell's preamp design will have increased distortion with that gain and input.
What? Where did that "generalization" come from?
What kind of amps are you talking about? Doubling down is not difficult for a good amp designer, just ask JC..
Output SOA protection circuitry is not "internal impedance" either.
jn
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