Feel lost when you sit around with your audiophile friends and they talk about this transistor gives you better high freq responce. Or this one gives you better mids. Or this chip amp has more warmth than that chip amp.
Im a guy who just likes to measure stuff. So have some doubts.
Its there a way to measure stuff like warmth of an amp,
As far as Im concerned and with the limited few amps I have put together. I like to just measure the output. In most cases so far I see that I have a flat response curve. i.e. feed it a 1 volt peak to peak signal from all freq from 20Hz to 20Khz. And Im happy when I see that the output curve out of the amp is flat. Sometimes Ill just do a Channel 1 - Channel 2. And if the curve is flat with no distortion call it a day.
Have read up as much as I can. And am still confused. When audiophiles are talking about differences in amps. Are they purely talking about stuff that can be measured or is there a component of stuff that cant be measured. Or am I just not measuring the right things the right way ?. Or is the magic in the imperfections which cant be measured ?.
Im a guy who just likes to measure stuff. So have some doubts.
Its there a way to measure stuff like warmth of an amp,
As far as Im concerned and with the limited few amps I have put together. I like to just measure the output. In most cases so far I see that I have a flat response curve. i.e. feed it a 1 volt peak to peak signal from all freq from 20Hz to 20Khz. And Im happy when I see that the output curve out of the amp is flat. Sometimes Ill just do a Channel 1 - Channel 2. And if the curve is flat with no distortion call it a day.
Have read up as much as I can. And am still confused. When audiophiles are talking about differences in amps. Are they purely talking about stuff that can be measured or is there a component of stuff that cant be measured. Or am I just not measuring the right things the right way ?. Or is the magic in the imperfections which cant be measured ?.
I reckon it all can be measured, just I'm not smart enough to know how to measure stuff like 'warmth'. I figure though it has something to do with noise, or rather lack of it.
As usual, it has mostly to do with frequency response (a tendency to favour the lows rather than the highs add "warmth") and to some extent, what kind of levels and distribution of 2:nd order distortion (a fair dose of 2nd (0,1-1%) and no or low levels of higher orders). Thats the receipt for warm/coold it seems.
The relatively high output impedance of tube amplifiers tend to give a slight rise in the lows due to the rising impedance of speakers down low. Add often low levels of feedback and transformers in the signal path and you have the above described situations at hand. No magic involved.
and.... "You listen to a system, not individual components".... 😉
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The relatively high output impedance of tube amplifiers tend to give a slight rise in the lows due to the rising impedance of speakers down low. Add often low levels of feedback and transformers in the signal path and you have the above described situations at hand. No magic involved.
and.... "You listen to a system, not individual components".... 😉
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Ok so TNT has given me my first clue. 0.1-1% variation in response can make a difference. So I was looking at the problem with the wrong resolution. Never even considered 0.1 to 1% as being meaningful or audible. I was happy if the curve looked flat. 1-2% was acceptable to me. Cause I never found / encountered / measured an amp with 0.1-1%
What % difference can the human ear perceive.
What % difference can the human ear perceive.
It is a fact that for all these subjective attributes there does not exist an equivalent absolute numeric number - but myriads of different individual opinions. And never ending debates what is meaningful and what is not. Many audiophiles defy any scientific approach with a set of numeric qualifying parameters declaring their own ears are the only reference for sound quality. So what is the goal? Nobody knows.
A thermometer should work. I know this reads like a bad joke, but read on...
Describing sound with words is difficult. "Warm" is about heat and temperature, not sound. Using "warm" to describe sound will mean very different things to different people. It's a bit like saying "this amp sounds yellow, and those speakers sound healthy". We are all getting used to some of the commonly (mis)used words to describe sound, but their meaning is usually rather unclear if your think about it.
Another problem is that it is extremely difficult to relate electronic and acoustic measurement data to perception of sound by humans. There are only very few examples where this works well (for example lots of high-order harmonic distortion is perceived as "bad" sound), but overall there is a huge gap between what we usually measure and what how we perceive sound, especially when it comes to HiFi.
The word "response" is mostly used for frequency response. The % figure I stated where for level of harmonic distortion (these are "new" tones not present in the input signal to the measured system and thus - generated by the DUT (device under test)) which do not effect level linearity. Level linearity with changing frequency is often called "frequency response".
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Maybe it relates to the speakers being used combined with the characteristic of the rest of the system.
Why speakers? In the past it was possible to go into a room loaded with all sorts and do A to B comparisons. Maybe it still is. 😉 I'm thinking back to the days when my father forked out for some AR's. He was bound to buy 3's due to price but of the range the only other model I would have bought was the 3 sided ones. Reason clarity. Only word I can think of to describe it. Other models irrespective of price - not for me.
Semiconductor amps against valve. I know little about valve amps but suspect semi's have more bandwidth available which allows them to produce distortions more accurately. Filters always let some through. Maybe what valves produce is "softer". Slower damped rise times when tested with a square wave etc. Cross over distortion is noticeable. No idea at what point it becomes un noticeable. Same with distortion.
Why speakers? In the past it was possible to go into a room loaded with all sorts and do A to B comparisons. Maybe it still is. 😉 I'm thinking back to the days when my father forked out for some AR's. He was bound to buy 3's due to price but of the range the only other model I would have bought was the 3 sided ones. Reason clarity. Only word I can think of to describe it. Other models irrespective of price - not for me.
Semiconductor amps against valve. I know little about valve amps but suspect semi's have more bandwidth available which allows them to produce distortions more accurately. Filters always let some through. Maybe what valves produce is "softer". Slower damped rise times when tested with a square wave etc. Cross over distortion is noticeable. No idea at what point it becomes un noticeable. Same with distortion.
You can measure a lot of things on amps and speakers. Where it gets a bit more complicated is when you try to correlate your measurements with people's perceptions of the sound - and especially when you then try to work out causal relationships between factors. In that sense, "a fool with an AP system is still a fool" to paraphase the old saying (and no, I haven't mentioned ASR at all... 😉 ).
That does not mean that measurements are irrelevant, but you should just recognize that measurements are a) a complex topic and b) not necessarily the point. People want a good sound, a fun hobby or similar, but very few people really want "the best", because what would you do then? To me it is the same as any other "high involvement" purchase (think car, house, expensive hobby equipment etc.) - of course the specs are important, but you never make a buying decision based only on specs.
That does not mean that measurements are irrelevant, but you should just recognize that measurements are a) a complex topic and b) not necessarily the point. People want a good sound, a fun hobby or similar, but very few people really want "the best", because what would you do then? To me it is the same as any other "high involvement" purchase (think car, house, expensive hobby equipment etc.) - of course the specs are important, but you never make a buying decision based only on specs.
Yeah, one must listen, listen a lot, and try to make connection with measurements and perceived sound and try to figure out what things affect what. Two amplifiers could measure the same (or be the same amplifier) but sound different if speakers are not the same, not at the same room, at the same position at same temperature, you not having same mood at same chair exactly at same location as before, listening fatigue already set in because you've had a long day, longer than half an hour? etc. many things change and its difficult to attribute some audible effect to some particular component in the system. A system consists of the whole playback chain in electronic domain, the loudspeakers that transform the sound into acoustic domain, the acoustic performance of the speaker and the room and finally you as observer with psychoacoustics involved, pressure variations in room received by your ears and interpreted by your brain affected by the coffee consumed, night sleep, mood, other senses triggered and so on. Can't escape it, just listen and have fun, try to measure and think what you hear and why.
When reading comments of others be critical about the context as already mentioned by others. If some one says warm maybe they felt warm because of nice room temperature, wool socks and tee with honey, nice company and good mood. Besides that, we don't know even the room, the speakers or the placement of speakers or the listener, what if the stylus has 10000 hours on it and all the top end is gone? What if the speaker is balanced too bright and one needs a "colored amplifier" to mellow it out, which could be completely opposite on some other set of speakers, or positioning, toe-in?
I bet the more you get years on it one difference rises above all, the frequency response including bandwidth and SPL capability. Its very hard to hear differences between anything unless there is change in frequency response. Sometimes my right speaker (3-way) mid is gone for days before I notice it in background listening use 😀 There is a bad solder joint in connector. A dramatic difference by measurement, hardly noticeable unless concentrating or getting into proximity where rooms influence to sound lessens. Two very different crossovers presets in DSP? again, noticeable difference but barely, blind testing not sure. 3ms extra delay on tweeters? very hard to hear other than change in frequency response, unless at proximity. Further away the sound doesn't change as the room mixes it up anyway. Do you know proximity on your speakers, where direct sound is louder than room sound, the phantom center is clear and so on? it doesn't seem to be that far, I have trouble extending it beyond two meters in quite standard living room. Listen outside this and it gets hard to hear any difference, get inside and everything is so much better like swapping the amp and speakers to something else completely. Brain does quite nice job adapting the situation for your awareness smoothing out some small differences until some threshold is met.
In the end, after lots of fiddling around, certain order of importance emerges and then you can shrug shoulders to some. I mean, everything matters and when everything (most) is "optimized" in the system including your mood, sound gets very good, but unless everything is optimized its very hard to hear difference what some particular thing makes if everything else is a mess. Yeah its possible to hear very small differences, accumulate enough of those to get very good sound, but I'm quite sure there ain't many who can do it, years of experience in critical listening I think. Its much easier to "hear" something is better because its visually more appealing, or costs more, or someone says its better, the brain colors the actual sound for better, no need for critical listening skills, a silver bullet. For this reason its a good thing to rely on measurements, try to get them right, learn how they relate to perceived sound, get confidence on the measurements and so on, to form a baseline. Have a reference system you can return to and do AB comparisons with. And, of course have fun doing it 🙂 After all there is a task to refine what you like to hear, which might not be obvious unless you've already done the learning.
I think when there is no glaring problems with the system its enjoyable, easy time for brain to connect to the music. Some problem that captures the subconscious attention, something that prevents emotional connection to the music, is bad. They probably show up in measurements like a resonance, or bad balance in room. Try to identify them while listening and then identify them in the measurements. I mean all the things that make you feel "something is not right but I'm not quite sure what". Or even the more obvious ones, like "where is the bass?". Fix those, and you are step closer. The bad and good thing is that you'll learn to hear more of "issues" 😀 but thats the salt, keeps you on the hobby for years, years of fun time discovering interesting nuggets 😀
When reading comments of others be critical about the context as already mentioned by others. If some one says warm maybe they felt warm because of nice room temperature, wool socks and tee with honey, nice company and good mood. Besides that, we don't know even the room, the speakers or the placement of speakers or the listener, what if the stylus has 10000 hours on it and all the top end is gone? What if the speaker is balanced too bright and one needs a "colored amplifier" to mellow it out, which could be completely opposite on some other set of speakers, or positioning, toe-in?
I bet the more you get years on it one difference rises above all, the frequency response including bandwidth and SPL capability. Its very hard to hear differences between anything unless there is change in frequency response. Sometimes my right speaker (3-way) mid is gone for days before I notice it in background listening use 😀 There is a bad solder joint in connector. A dramatic difference by measurement, hardly noticeable unless concentrating or getting into proximity where rooms influence to sound lessens. Two very different crossovers presets in DSP? again, noticeable difference but barely, blind testing not sure. 3ms extra delay on tweeters? very hard to hear other than change in frequency response, unless at proximity. Further away the sound doesn't change as the room mixes it up anyway. Do you know proximity on your speakers, where direct sound is louder than room sound, the phantom center is clear and so on? it doesn't seem to be that far, I have trouble extending it beyond two meters in quite standard living room. Listen outside this and it gets hard to hear any difference, get inside and everything is so much better like swapping the amp and speakers to something else completely. Brain does quite nice job adapting the situation for your awareness smoothing out some small differences until some threshold is met.
In the end, after lots of fiddling around, certain order of importance emerges and then you can shrug shoulders to some. I mean, everything matters and when everything (most) is "optimized" in the system including your mood, sound gets very good, but unless everything is optimized its very hard to hear difference what some particular thing makes if everything else is a mess. Yeah its possible to hear very small differences, accumulate enough of those to get very good sound, but I'm quite sure there ain't many who can do it, years of experience in critical listening I think. Its much easier to "hear" something is better because its visually more appealing, or costs more, or someone says its better, the brain colors the actual sound for better, no need for critical listening skills, a silver bullet. For this reason its a good thing to rely on measurements, try to get them right, learn how they relate to perceived sound, get confidence on the measurements and so on, to form a baseline. Have a reference system you can return to and do AB comparisons with. And, of course have fun doing it 🙂 After all there is a task to refine what you like to hear, which might not be obvious unless you've already done the learning.
I think when there is no glaring problems with the system its enjoyable, easy time for brain to connect to the music. Some problem that captures the subconscious attention, something that prevents emotional connection to the music, is bad. They probably show up in measurements like a resonance, or bad balance in room. Try to identify them while listening and then identify them in the measurements. I mean all the things that make you feel "something is not right but I'm not quite sure what". Or even the more obvious ones, like "where is the bass?". Fix those, and you are step closer. The bad and good thing is that you'll learn to hear more of "issues" 😀 but thats the salt, keeps you on the hobby for years, years of fun time discovering interesting nuggets 😀
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There seems to be a subconscious element to the language people use.
'Clean': the sound has been 'sanitised', like with a detergent that leaves behind a little bit of an unpleasant residue. E.g. an amplifier that uses lots of negative feedback to achieve low THD measurements, at the cost of a harsh tonal character of the residual distortion.
'Clinical': 'cleaned' with formaldehyde and/or bleach.
'Sweet': like a puritan who hates desserts, and when there's too little to complain about.
Then there's natural, clear, transparent... Why would any adjective be the first to pop into your mind, unless there's some connection?
'Clean': the sound has been 'sanitised', like with a detergent that leaves behind a little bit of an unpleasant residue. E.g. an amplifier that uses lots of negative feedback to achieve low THD measurements, at the cost of a harsh tonal character of the residual distortion.
'Clinical': 'cleaned' with formaldehyde and/or bleach.
'Sweet': like a puritan who hates desserts, and when there's too little to complain about.
Then there's natural, clear, transparent... Why would any adjective be the first to pop into your mind, unless there's some connection?
Its relative to something? what if clean sound to someone is still too nasty for another? Sweets all day long without proper meal in between? Yeah its very hard to connect written descriptions to personal perception without shared history.
Often we see very contradicting descriptions and comments on anything, and I like to think (mostly) everyone is right they just have different context which they base on. It can give some good insight if I really try to think why would some one say something, that's perhaps completely opposite what I think, or a group thinks. Ignoring it is sure way to stay in my own bubble, trying to think about it is nice way to chew the issue on multiple fronts and perspectives and hopefully lead up to better understanding. Fell for it multiple times, hopefully not that often in the future 😀
Often we see very contradicting descriptions and comments on anything, and I like to think (mostly) everyone is right they just have different context which they base on. It can give some good insight if I really try to think why would some one say something, that's perhaps completely opposite what I think, or a group thinks. Ignoring it is sure way to stay in my own bubble, trying to think about it is nice way to chew the issue on multiple fronts and perspectives and hopefully lead up to better understanding. Fell for it multiple times, hopefully not that often in the future 😀
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This in some twisted way wraps back to my orignal problem when I got started with Audio a few months back. Which is how do you pick the best sounding transistor from a bag full of transistors that would all work and all make music.
At another level Im just trying to fit into my growing circle of audiophile friends. Where most things are measured and discussed based on how much money you have thrown into the system. This worm was triggered yesterday with a comment made by a friend who said the MJs sound way better than the 5200 ics. And may brain right away went into thinking ok I have both how do I measure which is better.
I remember my dad buying his first Music real music system. It was at a shop in Kuwait back in 78. We drove from Tikrit to Kuwait in an old Toyota with no a/c to pick and buy the system. The shop had various rooms with various systems and brands and you could pick what you liked. They had Akai, Hitachi, Pioneer, Technique. my dad picked the Akai AM-2400 an Akai Tape deck, Akai spool player and a hitachi HT350 turn table. THe speakers were. Akai SW-177.
To me that was the best sounding system ever. But if you see the tech specs for the amp today. They sound pretty depressing.
But Im still going to try and replicate them down to the louse channel separation on the amp.
He gifted most of the system and speakers to the Maid who worked for us I was not around to grab them.
This happened when he had to move home to a tiny flat in a new city.
Today I see used and abused examples going for over a 1000$ in my country. i.e. https://www.etsy.com/listing/1335492188/vintage-akai-pair-of-3-way-speaker
I still have the Hitachi turntable though. And after freshening up the caps. The speed control now works and the direct drive motor holds a steady signal from the strobe.
At another level Im just trying to fit into my growing circle of audiophile friends. Where most things are measured and discussed based on how much money you have thrown into the system. This worm was triggered yesterday with a comment made by a friend who said the MJs sound way better than the 5200 ics. And may brain right away went into thinking ok I have both how do I measure which is better.
I remember my dad buying his first Music real music system. It was at a shop in Kuwait back in 78. We drove from Tikrit to Kuwait in an old Toyota with no a/c to pick and buy the system. The shop had various rooms with various systems and brands and you could pick what you liked. They had Akai, Hitachi, Pioneer, Technique. my dad picked the Akai AM-2400 an Akai Tape deck, Akai spool player and a hitachi HT350 turn table. THe speakers were. Akai SW-177.
To me that was the best sounding system ever. But if you see the tech specs for the amp today. They sound pretty depressing.
But Im still going to try and replicate them down to the louse channel separation on the amp.
He gifted most of the system and speakers to the Maid who worked for us I was not around to grab them.
This happened when he had to move home to a tiny flat in a new city.
Today I see used and abused examples going for over a 1000$ in my country. i.e. https://www.etsy.com/listing/1335492188/vintage-akai-pair-of-3-way-speaker
I still have the Hitachi turntable though. And after freshening up the caps. The speed control now works and the direct drive motor holds a steady signal from the strobe.
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Nice memory! as you see the sound of a system is just one thing that can have a good impression, there has been lots of other emotions attached to it like the memory of the event picking them up. Its luxury goods with lots of emotion and impulse involved and run by marketing teams, lots of myths and assumptions floating around so prepare to hear people saying anything and everything. In the end you just have to find out yourself 🙂
While you could take your friends word for the better transistor you could ask him why he thinks so to get more understanding, perhaps there is good rationale. You could also try them both and listen yourself if you hear any difference. Make sure to equalize (acoustic) frequency responses within 0.5db or closer or the louder one sounds better. You could ask this from your friend too if it was a controlled listening test he drew the conclusion, but you can likely interpret it form his answer without directly asking it and draw your own conclusion and test by yourself, or just use the one thats more handy for some other reason 🙂
While there probably is audible difference with transistors there are probably more in the circuit topology. Also everything is relative to listening level, one amplifier might sound better with low SPL use while another one wins in high SPL use. Every system sounds bad if its too loud for its capability, or for your ears.
Have fun!🙂
While you could take your friends word for the better transistor you could ask him why he thinks so to get more understanding, perhaps there is good rationale. You could also try them both and listen yourself if you hear any difference. Make sure to equalize (acoustic) frequency responses within 0.5db or closer or the louder one sounds better. You could ask this from your friend too if it was a controlled listening test he drew the conclusion, but you can likely interpret it form his answer without directly asking it and draw your own conclusion and test by yourself, or just use the one thats more handy for some other reason 🙂
While there probably is audible difference with transistors there are probably more in the circuit topology. Also everything is relative to listening level, one amplifier might sound better with low SPL use while another one wins in high SPL use. Every system sounds bad if its too loud for its capability, or for your ears.
Have fun!🙂
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You might find this article interesting. Just a couple quick excerpts below:
https://www.stereophile.com/content/carver-challenge
"The Carver Challenge
J. Gordon Holt
Is it possible to make a $700 "mainstream-audio" power amplifier sound exactly like a high-priced perfectionist amplifier? Bob Carver, of Carver Corporation, seemed to think he could, so we challenged him to prove it.
. . .
In essence, this is a test of the ability of one amplifier (the Carver) to cancel the output signal of the other (the Reference). Or, as Bob expressed it, to compare the transfer functions of the two.
A transfer function is nothing more than a statement of the relationship between the signal fed into a device and the signal that comes out of it. For example, a frequency-response specification is a description of the transfer function telling us how much an input signal of fixed amplitude and varying frequency will vary in amplitude at the output.
Bob's test hookup would show much more than frequency response differences. In fact, one of his most interesting statements, for those of the "every amplifier is the same except for frequency response" school, was that varying frequency response between the 1.0 and the reference amp made up only about 25% of the significant differences. Relative phase shift, source impedances (damping factors)—in short, every electrical difference between the amplifiers—would produce a signal at that test point between the Plus output terminals. When the amplifier outputs were identical, in all respects, there would be total cancellation—a null—of the difference signal. Bob's goal was a 70dB null, or an 0.03% difference between the two amps."
https://www.stereophile.com/content/carver-challenge
"The Carver Challenge
J. Gordon Holt
Is it possible to make a $700 "mainstream-audio" power amplifier sound exactly like a high-priced perfectionist amplifier? Bob Carver, of Carver Corporation, seemed to think he could, so we challenged him to prove it.
. . .
In essence, this is a test of the ability of one amplifier (the Carver) to cancel the output signal of the other (the Reference). Or, as Bob expressed it, to compare the transfer functions of the two.
A transfer function is nothing more than a statement of the relationship between the signal fed into a device and the signal that comes out of it. For example, a frequency-response specification is a description of the transfer function telling us how much an input signal of fixed amplitude and varying frequency will vary in amplitude at the output.
Bob's test hookup would show much more than frequency response differences. In fact, one of his most interesting statements, for those of the "every amplifier is the same except for frequency response" school, was that varying frequency response between the 1.0 and the reference amp made up only about 25% of the significant differences. Relative phase shift, source impedances (damping factors)—in short, every electrical difference between the amplifiers—would produce a signal at that test point between the Plus output terminals. When the amplifier outputs were identical, in all respects, there would be total cancellation—a null—of the difference signal. Bob's goal was a 70dB null, or an 0.03% difference between the two amps."
I did that on the 'tank' Micro Seiki mr711
And still holds.
I also eliminated most connectors and simplified the wiring (I did It shorter for the potentiometers)
My actual turntable Is a plastic (ex thorens 160...the economic one, not the aluminum) platter with a Toy 12V motor but the arm Is 10"!!! Ex Pioneer tl-12 modified....
I feel that we cannot measure everything that we can hear. Maybe some day before I am gone we will, I hope so. 🙂
I feel we can measure anything we can hear - and more - but that we can't interpret what the meters says and relate it to hearing + perhaps really don't know what to measure. I mean - we can measure down to -140 dB or so... no way hearing has that ability.
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Yes, 140db is great. Maybe some of the things we hear are in the time domain. The brain-ear function is not fully understood at this point in time. I hope it will be.