Buddy, nothing is worse than Boerebond (farmer co-op store) beer.
(Not that it mattered all that much, just an empty-break inbetween every 5-6 bottles. The life of those farm fares didn't start till the first ambulances arrived)
(Not that it mattered all that much, just an empty-break inbetween every 5-6 bottles. The life of those farm fares didn't start till the first ambulances arrived)
Everyone seems to do their opamp testing (by ear or by teat equipment) on ONE SINGLE OPAMP. Why is that? Wouldn't it be a LOT more telling to test them with TEN of them cascaded? That would be more real-world, methinks,. Typically you have two in a Phono preamp, one in a CD DAC, three more in a preamp, a few more in an equalizer, maybe three more in a crossover, and probably some more in the power amp. THEN the differences might be audible to more of us.
No. Each opamp needs different treatment and will perform differently in different circuit. They should be tested in the exact circuit where they are going to be used. A real circuit such as a preamp.
There are many questions to ask, for example:
(1) When is a buffer required?
(2) If gain is needed, how to distribute it?
(3) When is inverting topology needed?
(4) Where is the best position of the volume pot?
(5) Where is the sweet spot for each opamp?
At the end, I have to compare many different scenarios. Basically comparing many different designs to select the best one.
Even when people are saying the same words, and presuming you could get them to use the exact same cadence, timing and pitch on every utterance (these differences help make it even more obvious who's speaking, but aren't needed), you can still easily tell one person's voice from another. Here are two actors saying the exact same line:
https://www.youtube.com/watch?v=l2LkdNls4bw&feature=youtu.be&t=40s
Okay, maybe not the fairest comparison, an unknown voice vs. a famous one, but it makes the point.
It sucks as far as the tiny differences we're talking about in (current, reasonably good) opamps. These are tiny enough that even recording engineers can catch themselves "hearing differences" when turning a knob they think is having an effect, but then they discover it's on an adjacent, unused channel.
Different human voices are hugely, ridiculously different and unique by comparison.
What point are you making then? That its easy to tell different voices apart? Preaching to the choir if so - that has been my point all along and it seems there are no dissenters.
Given that as humans we find it quite natural to distinguish different people's voices, how does that impact the claim that's been made here that our long term audio memory sucks would you say?
Misunderstanding (about the use of this term: "long-term memory"), I think.
If we listen to clip-A, and then allow for some time (delay), then listen to clip-B, then try to compare, yes, we will have trouble and we can say that our long term audio memory sucks!
But that's because the information gained from listening to clip-A was not (or cannot be) properly stored in the long-term part of the memory. So instead we should rely on short term memory and listen to clip-B directly after clip-A (without any delay).
But in my long term memory I have information such as second order distortion effects, fatigue, wrong pitch/rhythm, etc. I can use them as "reference" in a blind test.
Yes but its not our long term memory for recognition that sucks. Recognition does not operate by making comparisons with other (say) voices that we're familiar with. I think its way more likely that our ability to do comparisons sucks - this is self-evidently true for visual comparisons even when its possible to do them almost instantaneously on the same page - Change blindness demonstration
I don't understand what you mean by that. Isn't recognition is about comparison? I mean, I know that a voice belongs to my son because in my memory there exist a record of my son's voice.
I think my writing was too terse. When you recognize your son's voice its not by comparison with other voices that you reach the conclusion its his voice. Recognition seems to operate more like a content addressable memory.
<afterthought> Think of recognition like this - depress the 'loud' pedal on a piano and sing a note close to the strings. The string that 'recognizes' the pitch of your voice will resonate, the others won't. At no point is there comparison between some detail of your voice and details of the other strings.
<afterthought> Think of recognition like this - depress the 'loud' pedal on a piano and sing a note close to the strings. The string that 'recognizes' the pitch of your voice will resonate, the others won't. At no point is there comparison between some detail of your voice and details of the other strings.
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We are social animals. Our brains have evolved with very specialized functions for recognizing danger and to a lesser extent safety. It's can be important to survival to recognize a friend or family member by voice in the dark at night, or at some distance. Therefore recognition and memory for those things are deeply embedded in System 1 mental processes.
Other, less specialized memory, is less fully optimized and debugged by natural selection. For most things, the way memory works is that pulling something from memory into conscious awareness essentially moves it or provides direct access to it rather then sending a copy to conscious awareness. If while it conscious awareness, the memory accidentally gets modified, such as by thinking about too much, then the old memory is essentially overwritten and the memory is permanently distorted.
Now that how memory works is better understood, police have to be much more careful about questioning witnesses so as not to cause distortion of witness memory. Some cases have been overturned due to resulting memory errors.
If op amps perform better than discrete circuits, then shouldn't all amplifiers be class D chips, or based on LM3886? Since the THD and noise specifications are fantastic!
And just a note on THD - THD is total harmonic distortion, not total distortion, or ringing, or intermodulation, or spikes on the signal due to instability, feedback, or static. I'm not saying I can hear the difference, but I can hear a difference between TL072 and NE5532, and I hear a difference especially when there is a large dynamic range involved, for example in the humble guitar amplifier.
And in my experience, my discrete amplifiers wipe the floor with my LM3886 amplifiers, especially for noise and hum. Sound quality is far superior. I recently built an amplifier for a friend, and for the protection of the LM, he opted for the chip, and after building his amp, I'm disappointed with the sound quality. Those chips pick up tons of noise, especially on the ground return wire. It's astonishing.
Anyway, I'm all for op amps - I think they certainly have their place, but I can believe many will be able to hear the difference between op amps and discrete circuits.
Audiophiles listen to their equipment with music. Music lovers listen to their music with their equipment. I'm first and foremost a music lover, and I've found myself in audiophile territory many times, and it's dangerous territory.
And just a note on THD - THD is total harmonic distortion, not total distortion, or ringing, or intermodulation, or spikes on the signal due to instability, feedback, or static. I'm not saying I can hear the difference, but I can hear a difference between TL072 and NE5532, and I hear a difference especially when there is a large dynamic range involved, for example in the humble guitar amplifier.
And in my experience, my discrete amplifiers wipe the floor with my LM3886 amplifiers, especially for noise and hum. Sound quality is far superior. I recently built an amplifier for a friend, and for the protection of the LM, he opted for the chip, and after building his amp, I'm disappointed with the sound quality. Those chips pick up tons of noise, especially on the ground return wire. It's astonishing.
Anyway, I'm all for op amps - I think they certainly have their place, but I can believe many will be able to hear the difference between op amps and discrete circuits.
Audiophiles listen to their equipment with music. Music lovers listen to their music with their equipment. I'm first and foremost a music lover, and I've found myself in audiophile territory many times, and it's dangerous territory.
Presumably, a 'perfect' ground layout and power supply layout, with 'perfect' supply decoupling/damping, would suit any opamp and enable meaningful 'rolling'.
Dan.
Dan.
In due time, that will be inevitable. (Kii-3)
(I'm a tech fetishist, an audiophile who can't make up his mind)
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I did a fair amount of research and implementation on an acoustical room equalizer which attempts to change the frequency response so that the response of a system in a room is as flat as possible. It worked extremely well! I believe in room equalization, but I believe it can be done without the DSP / automatic setting up bit. Measuring a response in a room and setting up an equalizer for that room is, IMO, an easier and more effective solution.
The Kii Three's do something different in the sense that they acoustically compensate. Still, these sorts of things can be done manually, and for far less than EUR10000. I've listened to those B&O things that apparently do the room correction thing, and honestly, I wasn't all that impressed. To me, room equalization and all that is just a marketing thing (especially when the price is pushed up by ten times simply because of the added DSP, which is actually super cheap).
I find the value of room equalization in public address where speakers are far from linear, and venues are echo chambers. For home theater or hi-fi, it's really not necessary. Speaker-room interactions can be beneficial when the system is set up correctly, especially in the lower frequencies. And, I challenge the Kii Three's to come anywhere near a pair of X2's or B&W 802D3's.
Class A: 100%
Class AB: 95%
Class D: 60%
I haven't heard a class D amplifier which can hold a flame to any AB or A amp (in league).
Ek verstaan wat jy sê, maar ek verstaan nie mooi wat jy bedoel nie? In elk geval, ek sou graag wou luister na daai Kii's.
Components round the op-amp as well... On some sensitive designs they had to be re-engineered when the op-amp manufacturer changed the size of the silicon. I have seen many instances where purchasing has bought different parts to what has been specified and there be problems with the circuit working correctly, these differences do equate to a possibility of one op-amp sounding different from another due to the whole circuit not being considered when the op-amps were swapped.
I wonder how on all these complex boards with HUNDREDS of op-amp on for instrumentation purposes they can get silly figures yet op-amps are bad for audio, again like ferrites and other components...
So which parts were altered ?.
How did 'the size of the silicon' affect ?.
If the supplies are decoupled/damped more than adequately and earths done correctly, in the application of opamp buffer stage or opamp low gain stage, stability should be guaranteed.
The only variable is then the opamp DUT.
Dan.
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