oscilloscopes
Jorge,
What I mean is that if you are measuring the output of an amp, say sin wave, music or whatever with an oscilloscope, the amp will respond differently to the scope then to say a dynamic speaker where the voice coil is constantly changing position in the magnetic gap. Different amps have different abilities to put out current into different loads. That is why I suggested earlier that amp comparisons should be done with different systems. Would current output be the same across the same frequency spectrum for a dynamic driver vs an electrostatic system? Aside from the fact that one may want prolonged testing periods to become acquainted with a component.
I am specifically interested in this because I want to build a gainclone (or I prefer to say OPamp or inverting Opamp) with parallel ICs for better current output into lower loads. I already have a pair of speakers I built that have very transparent/neutral mid and high end and I am still thinking about a pair of complementary low-end units. I think I am off thread a bit.
Anyway, IMHO and possibly in that of others, an amp is one part of a dynamic system and there are many factors to consider when comparing amps, components, etc...
Jorge,
What I mean is that if you are measuring the output of an amp, say sin wave, music or whatever with an oscilloscope, the amp will respond differently to the scope then to say a dynamic speaker where the voice coil is constantly changing position in the magnetic gap. Different amps have different abilities to put out current into different loads. That is why I suggested earlier that amp comparisons should be done with different systems. Would current output be the same across the same frequency spectrum for a dynamic driver vs an electrostatic system? Aside from the fact that one may want prolonged testing periods to become acquainted with a component.
I am specifically interested in this because I want to build a gainclone (or I prefer to say OPamp or inverting Opamp) with parallel ICs for better current output into lower loads. I already have a pair of speakers I built that have very transparent/neutral mid and high end and I am still thinking about a pair of complementary low-end units. I think I am off thread a bit.
Anyway, IMHO and possibly in that of others, an amp is one part of a dynamic system and there are many factors to consider when comparing amps, components, etc...
TESTING WITH EARS IN POCKET.
Hi,
Well, I did.
IMHO, optimizing an amp with a speaker connected to it is a rather tricky art of self-delusion.
In essence that amp may sound fine on that particular load and impedance curve but it does not guarantee good results on other speakers.
Not that there are too many amps about that can drive any kind of load with equal aplomb, but still.
Moreover, I still have to a way to measure colourations, dynamic behaviour etc.
Peter,
I sincerely hope you keep on posting here no matter what some moody member seems to have in mind.
All,
BTW, I don't think that what Fred is talking about is art.
To me it is a science we just aren't understanding yet.
In the meantime use the best instruments you have...your ears.
Some members here have spent a considerable part of their lives on music reproduction in various ways.
I don't feel we should trash their vast amounts of experience, after all those members have been pushing the envelope and some are partially responsible for the current state of music reproduction at home...
High-end gear is expensive for obvious reasons,here at the forum you all have a vast amount of knowledge available to you allowing you to build your own stuff and do even better than the state of the art .
All you need to have is a will to learn.
Cheers,
Hi,
Well, I did.
IMHO, optimizing an amp with a speaker connected to it is a rather tricky art of self-delusion.
In essence that amp may sound fine on that particular load and impedance curve but it does not guarantee good results on other speakers.
Not that there are too many amps about that can drive any kind of load with equal aplomb, but still.
Moreover, I still have to a way to measure colourations, dynamic behaviour etc.
Peter,
I sincerely hope you keep on posting here no matter what some moody member seems to have in mind.
All,
BTW, I don't think that what Fred is talking about is art.
To me it is a science we just aren't understanding yet.
In the meantime use the best instruments you have...your ears.
Some members here have spent a considerable part of their lives on music reproduction in various ways.
I don't feel we should trash their vast amounts of experience, after all those members have been pushing the envelope and some are partially responsible for the current state of music reproduction at home...
High-end gear is expensive for obvious reasons,here at the forum you all have a vast amount of knowledge available to you allowing you to build your own stuff and do even better than the state of the art .
All you need to have is a will to learn.
Cheers,
Re: The gainclone...
I don't care at all what topology it is, if I can use it well. It either produces satisfying results or not. Some of you like to play with circuits, I like to play with implementing those circuits. The end result is the only thing that really matters.
Isn't our hobby about music? In some way it's like food. You either like it or not and you always need more.
mikek said:....interestingly, i have observed that detractors of the douglas Self design approach on this forum simultaneously have an affection for the 'gainclone' designs which uses a near identical topology.....
I don't care at all what topology it is, if I can use it well. It either produces satisfying results or not. Some of you like to play with circuits, I like to play with implementing those circuits. The end result is the only thing that really matters.
Tube_Dude said:
I agreed...maybe because the gainclone is a complete package...no need to understand as the circuits works...like a Mc Donalds food...
Isn't our hobby about music? In some way it's like food. You either like it or not and you always need more.
Hi Peter..
Love your amplifier case designs....should consider setting up a small business.....trust moi....you'll eventualy make a fortune...
Now ....on the points i raised....all i was trying to show logically, and from first principals, was the inescapable fact that 'audible but unmeasurable' defects in power amps. simply do not exist.....
I think that is now clear....
Love your amplifier case designs....should consider setting up a small business.....trust moi....you'll eventualy make a fortune...
Now ....on the points i raised....all i was trying to show logically, and from first principals, was the inescapable fact that 'audible but unmeasurable' defects in power amps. simply do not exist.....
I think that is now clear....
Final comments part two...
In this thread, I have brought up case after case where psychological bias accounts for perceived differences that don't really exist. Others have brought similar perspectives and references to the discussion supporting my views.
People don't have to take my word for it, they can take the word of Tom Nousaine, or Douglas Self, or re-create their own blind or null tests. What I have presented has been well documented in a variety of places and can be readily verified. The bulk of it isn't opinion, it's fact.
To do a basic blind test you only need a CD with some test signals, A DMM ( to match levels) and someone to swap leads for you and keep track of your "guesses". Sure it's not a perfect test, but it's certainly an interesting place to start.
I asked who here thinks they could pick out a $300 Japanese mainstream integrated from high-end separates costing at least ten times as much in a blind test. Nobody answered.
For the most part, however, all of the above have been ignored by those who don't agree wtih my views. Instead, they've chosen to either ignore the subject matter completely and discuss firesign theater, see-thru cables and other off topic matters, or they refute my points with the following sorts of replies:
For what it's worth, I was in no way trying to discourage anyone from building their own audio gear. As I've said many times, I know from personal experience it's a very rewarding hobby. I think there are many satisfying DIY projects including amplifiers. I've posted to other threads here trying to be as helpful as possible.
I was also trying to save a few folks some money. As I said early on, in light of the evidence I've presented, it would seem to make more sense to spend your amplifier budget on things that make a measurable and audible difference and not waste money on things that apparently don't. I'm sorry if some of you don't agree with that.
Again, I sincerely wish all of you well with your projects and I wish mikek the best of luck if he chooses to pursue his views here.
You have my vote if but good luck trying convince several members here of that.mikek said:
In this thread, I have brought up case after case where psychological bias accounts for perceived differences that don't really exist. Others have brought similar perspectives and references to the discussion supporting my views.
People don't have to take my word for it, they can take the word of Tom Nousaine, or Douglas Self, or re-create their own blind or null tests. What I have presented has been well documented in a variety of places and can be readily verified. The bulk of it isn't opinion, it's fact.
To do a basic blind test you only need a CD with some test signals, A DMM ( to match levels) and someone to swap leads for you and keep track of your "guesses". Sure it's not a perfect test, but it's certainly an interesting place to start.
I asked who here thinks they could pick out a $300 Japanese mainstream integrated from high-end separates costing at least ten times as much in a blind test. Nobody answered.
For the most part, however, all of the above have been ignored by those who don't agree wtih my views. Instead, they've chosen to either ignore the subject matter completely and discuss firesign theater, see-thru cables and other off topic matters, or they refute my points with the following sorts of replies:
I had hoped this was a DIY forum that was open to all levels of audio DIY projects and opinions. I also hoped that people here would generally be of a more analytical mind and put more weight in statistics, measurements, logic and even common sense than your typical hardcore audiophile.various members said:
For what it's worth, I was in no way trying to discourage anyone from building their own audio gear. As I've said many times, I know from personal experience it's a very rewarding hobby. I think there are many satisfying DIY projects including amplifiers. I've posted to other threads here trying to be as helpful as possible.
I was also trying to save a few folks some money. As I said early on, in light of the evidence I've presented, it would seem to make more sense to spend your amplifier budget on things that make a measurable and audible difference and not waste money on things that apparently don't. I'm sorry if some of you don't agree with that.
Again, I sincerely wish all of you well with your projects and I wish mikek the best of luck if he chooses to pursue his views here.
Re: This indeed is a 'fun' thread...
Depends what it is that you're wanting to test.
A simple, static sinusoid stimulus is really a rather poor test signal beyond rather simple, static tests. Music signals are neither simple or static. To get an idea of a device's dynamic behavior, you need to feed it something with a bit more meat on its bones.
This is why more robust test signals such as Maximum-Length Sequences (MLS) have been developed (starting back in the mid-60s). So that devices can be tested under more dynamic conditions more closely resembling the dynamics of realworld music signals.
se
mikek said:
Depends what it is that you're wanting to test.
A simple, static sinusoid stimulus is really a rather poor test signal beyond rather simple, static tests. Music signals are neither simple or static. To get an idea of a device's dynamic behavior, you need to feed it something with a bit more meat on its bones.
This is why more robust test signals such as Maximum-Length Sequences (MLS) have been developed (starting back in the mid-60s). So that devices can be tested under more dynamic conditions more closely resembling the dynamics of realworld music signals.
se
Topological acuity....
HUH????
In what ways are these gainclone's topology 'near identical' to Self's complementry output topologies? Does an input ltp define the amp???
Well, whatever 'first principals' you're talking about, your arguments might make more sense if your topology comments indicated that you could actually read a schematic???
mikek said:....interestingly, i have observed that detractors of the douglas Self design approach on this forum simultaneously have an affection for the 'gainclone' designs which uses a near identical topology.....
HUH????
In what ways are these gainclone's topology 'near identical' to Self's complementry output topologies? Does an input ltp define the amp???
Well, whatever 'first principals' you're talking about, your arguments might make more sense if your topology comments indicated that you could actually read a schematic???
MELISSA
Hi,
Surely Fred, Eric, Peter, myself and no doubt many others here could advise on how to save money when it must come to that too.
All of the people mentioned surely take measurements too, we just take them as assurance every is working properly and to have an idea of what can be expected soundwise.
After that we listen, think and tinker till it sounds right...
If you think that differences between components, boutique or not can't be measured than please think again for they can.
The crux however is in how to read the measurements and relate them to sonic attributes.
So, that would make for a measurable and audible difference, would it not?
Granted, there are a mumber of things we hear but can't measure.
Does it than follow it is just not there?
Distortion is more than what any measurement gear will show, distortion can be anything that was not there at the input.
A nulling test may be helpful but it certainly does not tell the whole story, and as far as I'm concerned it will all depend on how you, the user will arrive at conclusions.
There are at least 50 cheap tricks I can think of that have the potential of improving a system that don't cost an arm and a leg and won't likely give you a measurable improvement but certainly an audible one.
The only thing I notice is that the majority of people aren't even willing to try out even the simplest of experiment, no...they'd rather talk it down than try it.
Oh, and please do replace those Wondercrap caps with something half decent...they do sound like caramel candy, not that you can measure that...
Cheers,
/Always look at the bright side of life.
Hi,
Surely Fred, Eric, Peter, myself and no doubt many others here could advise on how to save money when it must come to that too.
All of the people mentioned surely take measurements too, we just take them as assurance every is working properly and to have an idea of what can be expected soundwise.
After that we listen, think and tinker till it sounds right...
If you think that differences between components, boutique or not can't be measured than please think again for they can.
The crux however is in how to read the measurements and relate them to sonic attributes.
So, that would make for a measurable and audible difference, would it not?
Granted, there are a mumber of things we hear but can't measure.
Does it than follow it is just not there?
Distortion is more than what any measurement gear will show, distortion can be anything that was not there at the input.
A nulling test may be helpful but it certainly does not tell the whole story, and as far as I'm concerned it will all depend on how you, the user will arrive at conclusions.
There are at least 50 cheap tricks I can think of that have the potential of improving a system that don't cost an arm and a leg and won't likely give you a measurable improvement but certainly an audible one.
The only thing I notice is that the majority of people aren't even willing to try out even the simplest of experiment, no...they'd rather talk it down than try it.
Oh, and please do replace those Wondercrap caps with something half decent...they do sound like caramel candy, not that you can measure that...
Cheers,
/Always look at the bright side of life.
Rebutal
An amplifier has memory. The instantaneous output voltage will be a function of input voltage and previous input history and propagation delay and distortion.
In other words an infinite number of sinewaves is an excellent test signal. Not a single sinewave.
Is THD is the same thing as TD? You hear TD not THD.
I disagree with the premise that measurement is comprehensive. If something is audible (repeatably) then it is measurable. However, it does not follow that if something cannot be measured then it cannot be heard.
Re: Final comments part two...
How is taking somebody's word on it a fact?
I had hoped this was a DIY forum that was open to all levels of audio DIY projects and opinions. I also hoped that people here would generally be of a more analytical mind and put more weight in statistics, measurements, logic and even common sense than your typical hardcore audiophile.
WE ARE!!!!!! You the one trying to disuade people from veiwpoints achieved from there own experiences and efforts, as well as the efforts of hundreds of others many of them talented engineers (since that seems to be the bias for credibility).
Tell me how the "don't bother some one else has already proved it doesn't matter" approach advance the art or science? Why should the opionions of a few advocates of double blind testing, clinging to a veiwpoint based on a pretty simplistic premise, outweigh the work of others with more open minds and vastly more experience.
For what it's worth, I was in no way trying to discourage anyone from building their own audio gear. As I've said many times, I know from personal experience it's a very rewarding hobby. I think there are many satisfying DIY projects including amplifiers. I've posted to other threads here trying to be as helpful as possible.
People don't have to take my word for it, they can take the word of Tom Nousaine, or Douglas Self, or re-create their own blind or null tests. What I have presented has been well documented in a variety of places and can be readily verified. The bulk of it isn't opinion, it's fact.
How is taking somebody's word on it a fact? I wasn't there to hear it or investgate to limits of the test setup. You can't tell how something sounds only by reading about someone elses listening experience
I had hoped this was a DIY forum that was open to all levels of audio DIY projects and opinions. I also hoped that people here would generally be of a more analytical mind and put more weight in statistics, measurements, logic and even common sense than your typical hardcore audiophile.
WE ARE!!!!!! You the one trying to dissuade people from viewpoints achieved from there own experiences and efforts, as well as the efforts of hundreds of others, many of them talented engineers (since that seems to be your bias for credibility).
Tell me how the "don't bother someone else has already proved it doesn't matter" approach advance the art or science? Why should the opinions of a few advocates of double blind testing, clinging to a viewpoint based on a pretty simplistic premise, outweigh the work of others with more open minds and vastly more experience?
For what it's worth, I was in no way trying to discourage anyone from building their own audio gear. As I've said many times, I know from personal experience it's a very rewarding hobby. I think there are many satisfying DIY projects including amplifiers. I've posted to other threads here trying to be as helpful as possible.
Oh Please! The very rational for this thread was to tell others that efforts to make the best sounding DIY equipment they could were bound to ultimately pointless since relatively simple nulling test and blind listening test will result in efforts no better than results achieved by buying low priced competently designed commercial amplifiers. Tell me what the rewarding part of building equipment for you is. I kind got the idea that your sense of reward was saving people from buying into the high end "hoax" you so desperately image is being perpetuated on a helpless and trusting audience here.
I was also trying to save a few folks some money. As I said early on, in light of the evidence I've presented, it would seem to make more sense to spend your amplifier budget on things that make a measurable and audible difference and not waste money on things that apparently don't. I'm sorry if some of you don't agree with that.
Now your the arbiter of what is measurable and audible and merit of the cost vs. audibility of improvements. This is something I would never dare to do, since everyone's level of involvement is different in this hobby. I don't think you have read much of the forum since approach to low effort and low cost projects are discussed as often as what you consider the delusional audiophile approach. The extreme interest in the whole gain clone thread is proof that low complexity and low cost efforts are important to a great number of people here.
I am waiting for the inevitable response about my emotional investment. I wonder if you might be the one with the greatest emotional investment, to an idea that many feel does disservice not only others but yourself as well. The vast majority of people are here to find out what might make an amplifier better and not how to prove to themselves that it makes no difference. Perhaps if you can to, if you will put away your hopeless dogma and intellectual dishonesty. We all await your "final" final
reply.
Sincerely,
Fred
nw_avphile said:
How is taking somebody's word on it a fact?
I had hoped this was a DIY forum that was open to all levels of audio DIY projects and opinions. I also hoped that people here would generally be of a more analytical mind and put more weight in statistics, measurements, logic and even common sense than your typical hardcore audiophile.
WE ARE!!!!!! You the one trying to disuade people from veiwpoints achieved from there own experiences and efforts, as well as the efforts of hundreds of others many of them talented engineers (since that seems to be the bias for credibility).
Tell me how the "don't bother some one else has already proved it doesn't matter" approach advance the art or science? Why should the opionions of a few advocates of double blind testing, clinging to a veiwpoint based on a pretty simplistic premise, outweigh the work of others with more open minds and vastly more experience.
For what it's worth, I was in no way trying to discourage anyone from building their own audio gear. As I've said many times, I know from personal experience it's a very rewarding hobby. I think there are many satisfying DIY projects including amplifiers. I've posted to other threads here trying to be as helpful as possible.
People don't have to take my word for it, they can take the word of Tom Nousaine, or Douglas Self, or re-create their own blind or null tests. What I have presented has been well documented in a variety of places and can be readily verified. The bulk of it isn't opinion, it's fact.
How is taking somebody's word on it a fact? I wasn't there to hear it or investgate to limits of the test setup. You can't tell how something sounds only by reading about someone elses listening experience
I had hoped this was a DIY forum that was open to all levels of audio DIY projects and opinions. I also hoped that people here would generally be of a more analytical mind and put more weight in statistics, measurements, logic and even common sense than your typical hardcore audiophile.
WE ARE!!!!!! You the one trying to dissuade people from viewpoints achieved from there own experiences and efforts, as well as the efforts of hundreds of others, many of them talented engineers (since that seems to be your bias for credibility).
Tell me how the "don't bother someone else has already proved it doesn't matter" approach advance the art or science? Why should the opinions of a few advocates of double blind testing, clinging to a viewpoint based on a pretty simplistic premise, outweigh the work of others with more open minds and vastly more experience?
For what it's worth, I was in no way trying to discourage anyone from building their own audio gear. As I've said many times, I know from personal experience it's a very rewarding hobby. I think there are many satisfying DIY projects including amplifiers. I've posted to other threads here trying to be as helpful as possible.
Oh Please! The very rational for this thread was to tell others that efforts to make the best sounding DIY equipment they could were bound to ultimately pointless since relatively simple nulling test and blind listening test will result in efforts no better than results achieved by buying low priced competently designed commercial amplifiers. Tell me what the rewarding part of building equipment for you is. I kind got the idea that your sense of reward was saving people from buying into the high end "hoax" you so desperately image is being perpetuated on a helpless and trusting audience here.
I was also trying to save a few folks some money. As I said early on, in light of the evidence I've presented, it would seem to make more sense to spend your amplifier budget on things that make a measurable and audible difference and not waste money on things that apparently don't. I'm sorry if some of you don't agree with that.
Now your the arbiter of what is measurable and audible and merit of the cost vs. audibility of improvements. This is something I would never dare to do, since everyone's level of involvement is different in this hobby. I don't think you have read much of the forum since approach to low effort and low cost projects are discussed as often as what you consider the delusional audiophile approach. The extreme interest in the whole gain clone thread is proof that low complexity and low cost efforts are important to a great number of people here.
I am waiting for the inevitable response about my emotional investment. I wonder if you might be the one with the greatest emotional investment, to an idea that many feel does disservice not only others but yourself as well. The vast majority of people are here to find out what might make an amplifier better and not how to prove to themselves that it makes no difference. Perhaps if you can to, if you will put away your hopeless dogma and intellectual dishonesty. We all await your "final" final
reply.
Sincerely,
Fred
Re: Topological acuity....
On the contrary, a single-frequency sinusoid is anything but 'static'....this is only true of pure D.C. Despite a huge variety of 'new' test signal concocted by many to approximate real music signals, (surely an impossible task!), no evidence has been presented anywhere, (and this includes the learned A.E.S), that these demonstrate deficiencies in power amps. that cannot be revealed with cosinusoidal stimuli....
Pkamp....i have studied this particular chip's schematic with some rigour......it is infact a widlar-thomson derivative....i.e: the same topology in essence recommended by D. Self...my point is, differentiating between topologies by merely listening to them is shown to be fraudulent by the D.Self/gainclone debate on this forum...
Folks, if we all concetrate on point by point rebutals, that do not degenerate into off topic put downs, this thread would get interesting....
Steve Eddy said:
On the contrary, a single-frequency sinusoid is anything but 'static'....this is only true of pure D.C. Despite a huge variety of 'new' test signal concocted by many to approximate real music signals, (surely an impossible task!), no evidence has been presented anywhere, (and this includes the learned A.E.S), that these demonstrate deficiencies in power amps. that cannot be revealed with cosinusoidal stimuli....
pmkap said:
HUH????
In what ways are these gainclone's topology 'near identical' to Self's complementry output topologies? Does an input ltp define the amp???
Well, whatever 'first principals' you're talking about, your arguments might make more sense if your topology comments indicated that you could actually read a schematic???
Pkamp....i have studied this particular chip's schematic with some rigour......it is infact a widlar-thomson derivative....i.e: the same topology in essence recommended by D. Self...my point is, differentiating between topologies by merely listening to them is shown to be fraudulent by the D.Self/gainclone debate on this forum...
Folks, if we all concetrate on point by point rebutals, that do not degenerate into off topic put downs, this thread would get interesting....
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