Jay, it's quite common now to have opamps with 100 dB PSRR at 20 kHz and 20 times better at LF.
That's what I'm talking about. PSRR doesn't do anything on this hypothetical power supply garbage... (well, of course my conclusion was not based on that level of PSRR you mentioned)
Feed them from a 7815 regulator and the real input referred noise emanating from noise on the supply rails is pico volts.
I have found that opamp circuits can never sound good enough with power supply made from 7815/7915. These ICs measured very good (we all know that), but the perceived sound is very bad, Bonsai... (Power supply impedance?)
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I always feel that I have something special, better than what is likely measured by the IQ test
Which leaves the following options :
- God
- A narcissist of a different order
- Alien
- Steve Jobs
That's what I'm talking about. PSRR doesn't do anything on this hypothetical power supply garbage... (well, of course my conclusion was not based on that level of PSRR you mentioned)
I have found that opamp circuits can never sound good enough with power supply made from 7815/7915. These ICs measured very good (we all know that), but the perceived sound is very bad, Bonsai... (Power supply impedance?)
Dear me. What am I dealing with here?
I'm outta this specific discussion.
😀
Aren't the first and last options the same?
I'm still to meet the first, call me objective and a sceptic.
(Stanley Tucci in Transformers 4 reminded me of someone. Apart from 'My name Muerte')
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Dear me. What am I dealing with here?
Which part, the PSRR or the 7815?
If you think 7815/7915 is as good as the measurement shows, tell me one good reason why you are not using it for your Ovation Symphony preamp?
I'm still to meet the first, call me objective and a sceptic.
There are many objectivists in audio. Of these, those who believe in the first is hypocrite, no doubt. It's like you think 7915 is good but you don't want to use it.
tell me one good reason why
Challenging an opponent means you ran out of arguments.
(Not my divine wisdom, I've had thorough professional training in conversation/interview techniques. Alien is out, that one does not crave for an audience)
Dear me. What am I dealing with here?
I'm outta this specific discussion.
😀
I have some friends that call it the UCO - the Universal Cop-Out. As soon as a discussions gets specific and is no longer content free, people tend to withdraw behind a personal wall of '... but it sounds bad'. Or good, depending on what is most convenient at that moment.
That is then the end of any intelligent discussion.
Jan
Challenging an opponent means you ran out of arguments.
That's not the case. He wanted to get out of the discussion and I just wanted to pull him in 😀 BTW, I guess most of those (psychology) wisdoms in your trainings are based on statistics. It means, it works on the majority but not on the outliers.
Which leaves the following options :
- God
- A narcissist of a different order
- Alien
- Steve Jobs
You forgot one: - A normal human.
It is normal for everyone to think they are somehow more special than everyone else. Some psychologists believe this is because we are privy to what is going on inside our own conscious awareness, but can only observe other people externally. The additional richness of detail we observe in ourselves creates an illusion we are more special. This is similar in some ways, in terms of System 1 processing, to the perception of optical illusions or aural illusions. The primary difference is a very subjective one: most people can admit they see optical illusions, as there is no particular stigma associated it.
The current arguments, pro and con, sure seem to fit in pretty well with what is described here: http://www.nytimes.com/2011/06/15/arts/people-argue-just-to-win-scholars-assert.html?_r=1
I love DIY Audio Forum 😛
Logic displayed often beats that of Monty Python shows 😀
https://youtu.be/kQFKtI6gn9Y
Logic displayed often beats that of Monty Python shows 😀
https://youtu.be/kQFKtI6gn9Y
Challenging an opponent means you ran out of arguments.
Many arguments naturally tend to take the form of debate, even among scientists. As a debating (also courtroom) tactic, attempts to impeach the character of a witness occur frequently. Right or wrong, it is something that humans often do automatically, and in the debates that take place in this forum both sides sometimes do it.
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He wanted to get out of the discussion and I just wanted to pull him in
Means you're not God or Steve Jobs either.
Means you're not God or Steve Jobs either.
Geez... so only one possibility left? 😡
A narcissist of a different order. Hmmm... A narcissist I'm not. But with the extra "of a different order" it at least sounds good... 🙄
Jay, if you have such a High IQ, do some calculations.
Output ripple of 7815: 50 dB down on input ripple typically. On a good PSU with ~200mA total current draw its 100mV so on the 7815 output its about 300uV (wideband noise is about 10x lower than this on a 7815)
LF PSRR on a good opamp is 120dB = 1000000x
300uV/10^6 = 0.3nV or 300 pV which is a conservative number.
(Assumption: Unity gain configuration)
If you have discrete circuits doing this I'm all ears but don't expect me to get into a discussion about it with you any further.
I am definitely outta here now. Some one else can deal with your machinations.
Output ripple of 7815: 50 dB down on input ripple typically. On a good PSU with ~200mA total current draw its 100mV so on the 7815 output its about 300uV (wideband noise is about 10x lower than this on a 7815)
LF PSRR on a good opamp is 120dB = 1000000x
300uV/10^6 = 0.3nV or 300 pV which is a conservative number.
(Assumption: Unity gain configuration)
If you have discrete circuits doing this I'm all ears but don't expect me to get into a discussion about it with you any further.
I am definitely outta here now. Some one else can deal with your machinations.
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