Absolutely.
Sometimes it happens in experiments that contraditionary evidence (or lack of evidence for the preexisting beliefs) is not only neglected but actually evokes even more confidence in these prior beliefs.
I understand that and it up to a certain degree it is justified; for example in case of a significance level criterion, nobody wants to accept results with a p = 0.04999872 as evidence just because it is below 0.05 .
Despite the fact that the p-value isn´t meant to be used in such a way it is often used as such.
But it suprizes me that people are claiming to be objectivists/rationalists without even bother to think about these questions.
Might be that they often believe in knowing everything already and that no contradictionary evidence is possible but that such a point of view is highly questionable should be obvious.
Something broken between your eyes and your brain ? ;-)
(Sorry, could not resist)
Proof exists in formal logic/mathematics but not in observational sciences; should be obvious but if you want to learn more about it, have a look in good literature on philosophy of science.
As other members already have said, we addressed that point in other threads, so you should be able to memorize the fact that i stated doing work also in the "audio business".
As these questions arise quite frequently information was often given about things that can be heard but are not measureable; especially our perception of spatial effects that is in many instances virtual for the usual two channel stereophony.
So, you should ask first if Zung is talking about perception or about the "sound waves" that _you_ mentioned
Ask Beethoven about that! Some remember the association between measurements and sound...It's called experience.
Did you measure this?
The Fairchild
LM7815 spec says 90uV/Vo in a 10-100KHz BW = 1.35mV
LM317 spec says 0.003%/Vo in a 10-10KHz BW = 450uV
The specs are not comparing the same measurement BW but ...
I have a HP/Agilent 11715A AM/FM test source that was used to measure a 8901A,B modulation analyzers phase noise or residual FM. They had a mod to upgrade it, change out LM78(9)xx for LM317/337, I wonder why they did that? I assume it was done to reduce the phase noise of the oscillators. They constructed the units RF section, to float on rubber shock absorbers, used feed thru caps to wire the supplies into the RF enclosure, used cap multipliers on each supply inside the enclosure. That is what I call a well designed PS for sensitive RF circuits. It also had a RFI line filter. I think the PS design should work well for audio frequencies too 🙂 11715A has a FM band modulator, that I use to test align low thd Fm detectors in tuners.
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Dreamth I don't know where you are coming from, but you certainly are biased about what makes quality audio.
First, you have no real understanding of circuits and their respective 'quality'. This is probably because you have not studied electronics.
You have strong opinions that contradict much of what we have learned AND MEASURED over the last 40 years. For example, if you tell Richard Marsh, that you LIKE coupling caps, he is going to be surprised, because he has listened to, and MEASURED caps in every which way, over the last 40 years, and he knows that they add measurable deviation, as I do and measured, so IF you prefer caps, then what is it about caps that you like? Do you like the added DA? That would be my first guess, however it might be that you prefer the circuits that are necessarily cap coupled, which usually implies a single ended supply, instead of a dual supply. Unfortunately, when you use a dual supply, you usually take the DC bias off the coupling caps which usually makes them have more non-linear distortion. This is especially true with tantalum caps. Aluminum electrolytics usually add the most DA, a 'linear' deviation that changes the audio signal.
Again, what is it that you prefer? Or are you just trying to ....
First, you have no real understanding of circuits and their respective 'quality'. This is probably because you have not studied electronics.
You have strong opinions that contradict much of what we have learned AND MEASURED over the last 40 years. For example, if you tell Richard Marsh, that you LIKE coupling caps, he is going to be surprised, because he has listened to, and MEASURED caps in every which way, over the last 40 years, and he knows that they add measurable deviation, as I do and measured, so IF you prefer caps, then what is it about caps that you like? Do you like the added DA? That would be my first guess, however it might be that you prefer the circuits that are necessarily cap coupled, which usually implies a single ended supply, instead of a dual supply. Unfortunately, when you use a dual supply, you usually take the DC bias off the coupling caps which usually makes them have more non-linear distortion. This is especially true with tantalum caps. Aluminum electrolytics usually add the most DA, a 'linear' deviation that changes the audio signal.
Again, what is it that you prefer? Or are you just trying to ....
We have emphasized the importance of controlled listening tests quite frequently over the years.
But people claiming to be objectionists representing the scientific basis have a bigger obligation to bring real science to the table.
Despite all the evidence that was presented pointing to the fact why controlled (blind) listening tests in general (and ABX tests specificially) might lead to false negatives if no training is used and propper controls are omitted, you´ll see demands for these kind of test without any hint to the mandatory procedures.
To illustrate this i´ve linked the thread on hydrogenaud.io about a statement used in the Foobar ABX plugin.
I´ve stated an undisputable fact (the statement used before in the plugin was false and misleading) but faced religious like resistance from people who surely belief they are working in favor of science but are in reality more interested in "cargo-cult-science".
Fortunately the developer´s stance was reasonable......
I can find a few hundred amplifiers and preamplifiers from very reputable companies that were considered year by year top notch audio components by the same magazines that applauded your designs... What makes your design better than a good capacitor coupled design of Kenwood , Yamaha , Sansui, Nakamichi, NAD?
Is it the fact that it was Made in USA with very expensive components and sold only to the most rich people? Then i'm sorry to tell but they are a minority and their opinion do not count.
I know somebody in my country who designed a bipolar design and then convinced(for that i have proof!) the owner of the most expensive high end shop in my country to buy one for 2700 euros(to be precise) after he admitted that he never heard anything better. That was a diy 2x120w/8ohm amplifier!!! He bought that for his own use and have it at home on the most expensive Martin Logan's. Now i have to tell you that the shop sells the most expensive amps and speakers on the planet for 15 years now. I heard that amp on Tannoy Red 15 and also on the most expensive Scaspeak speakers along with other audiophile 30 people listening to some other expensive amps considered the same...high end amps as yours. I also heard some amps of the 80's which are as good as the best amps of today, no matter the price tag. I'm not buying into complementary matched fet doctrine just because they are unobtainium for most of us. I don't agree with any doctrine at all in the end...Good design does not depending on topology or top components quality. A 2A3 or 300B 1.5w amp can sound terrific on the right speakers.But other cheaper valves can do equally well and the valves world have their own wars about which valve or OT is better...
Judging the amps separately from speakers and the room where you are going to listen to the whole system is a bit useless too. I have a few friends who'd never buy or build a silicon amp at all considering silicon design boring but i never get full contact with the,.I just respect their opinions as i'm not in possession of their ears. By the way...when digital sources came on stage there was no balanced output and all players output was the same with any preamp output : capacitor coupled. Many of the high end products of today are still coupled with capacitors at the input, output and/or interstage.
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I'd like to know more about the conditions. Clearly this was not an LED, and unlikely to be fluorescent, so almost surely an incandescent light. I presume it was possible to effectively filter out everything outside visible light, so as to insure that they weren't actually feeling heat, but I suspect it's the heat from the light source they were feeling.
When I first heard 128k MP3 playback it sounded fine to me (I'm a little ashamed to admit, but as a partial excuse I was already old enough my hearing probably stopped above 15kHz), and I wondered what all the commotion on the Internet about it 'sounding like crap' was about. I did more reading and some experimenting. Some awful dialup-speed audio streaming gave me some hints at what to listen for, a touch of the wishy-washy phasing sound that was so overwhelming at lower bit rates. I got an encoder and encoded a jazz CD with a bright snare drum, and I heard a difference - there was a 'smearing' in the time domain of the snare crack. Encoding it at lower bitrates made this smearing more obvious. This jibed with what I had been reading about MP3 coding, that it takes "snapshots" of the spectrum every N (maybe 10 or 50) milliseconds (and of course it deletes frequencies calculated as being inaudible), and the playback crossfades between successive snapshots. I might never have heard it if I hadn't had some hints for what to listen to.
So yes, one's sensory acuity can indeed be sharpened with training and knowledge of what to listen/look/feel for.
And of course once one "hears" (actually recognize that one is already hearing it!) something like this, it can be hard to tune it out and NOT hear it.
Again, I suspect they actually felt the heat from an incandescent light source, but it would be interesting to repeat the experiment with modern low-heat-producing light sources and good filters. Radiant heat of sufficient intensity is easily detected by skin.
Also, I've seen the light beam of a helium-neon laser shone on a transistor heat it up and lower Vbe when driven by a constant current source, demonstrating that even "pure" visible light can get converted into heat.
I don't so much question the experiment's results so much as I question the conclusion that skin can be directly "light sensitive." The eye can easily detect a short burst of visible photons, but (I speculate) skin on the hand needs enough radiation on it to be felt as heat.
just in cased you missed this link:
Nichicon Muse ES bipolar caps measured: <-120dB THD, <-140dB IMD
Nichicon Muse ES bipolar caps measured: <-120dB THD, <-140dB IMD
I questioned myself the same things, but i thought that maybe they took care about these aspects somehow. The experiment was depicted in this book that i read 15 years ago:
Psihologia mecanismelor cognitive - Mielu Zlate
It's in Romanian and it's written by a professional...high academia profile for decades. Translation :The Psychology of Cognitive Mechanisms...
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Some "amazing" things are happening - the big semiconductor makers have been dropping small-volume "boutique" parts as you say, but some smaller makers have been picking them up. This company is making the LM394 "supermatched" dual transistor: Voltage Transistors It (and some other small semiconductor houses) has recently also started (re)making some of the synthesizer-specific analog chips (formerly made by SSM and CEM) that were used in popular music synthesizers of the 1970s and 1980s. There's a small group of enthusiasts who are very happy about this.
Some of this is happening in the 'audio' field as well, with Linear Systems making the low-noise jfets that Toshiba obsoleted.
Thanks for the advice Richard. I have been using dummy load resistors on the output of my regs for about 15yrs now with good results. I like the idea of a pre-reg also.
THAT has been making low noise NPN/PNP (<1 nV) pairs for a long time. I can feel most red laser pointers BTW they leak enough IR.
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I began building a digisound 80 modular synth when I was a kid, never quite finished it but what I had was put to good use as an amusing CB radio roger bleep
I heard about some cheap replacement that works very well just not as low noise...I can't remember the brand name.
Me too. I ran out of money before I could afford a keyboard to go with it. Went in the skip when I got divorced.
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