Here is the real hoax of the simulation, the opamp simulated is an A826AN, which is a dual op amp. Now think - how can a dual op amp have its power rails connected twice ? A dual only has one capability for V+ and V- In the simulation schematic the psu rails go to that same op amp rails twice defying any logic.
Nat Semi's program needs to be rewritten
Back to the listening ..... Cheers / Chris
Nat Semi's program needs to be rewritten
Back to the listening ..... Cheers / Chris
Let me clarify, The simulation program written by Nat Semi has allowed a Dual Op amp architecture internally to be redefined. It should immediately disallow such a simulation as the simulation is not within real world parameters.
You cannot connect physically a dual opamp Channel A and Channel B rails with different components, they are shared internally by the op amp. Neither should it be possible to simulate or draw any conclusion from such misuse of connection.
Back to the listening ... Cheers / Chris
You cannot connect physically a dual opamp Channel A and Channel B rails with different components, they are shared internally by the op amp. Neither should it be possible to simulate or draw any conclusion from such misuse of connection.
Back to the listening ... Cheers / Chris
Armchair warrior returns for more....
The man who scoffs at the endeavour of others but does nothing to justify his claims or insults and whom relies on others to simulate to prove his point.
Did you make one yet and listen to it - did anyone ?
Ooh that's right....no one did.....haha !
Use my mind ?
I use my mind and fingers to play densely scored sheet music that you'd probably ask me to explain.
Why not learn to play a musical instrument then relate that to what you hear from your system - I'll bet it sounds like sh... a bit like your attitude.
..and btw...I don't need these op amps or related mods and am not following anyone.
Now, if you want to be really rude to me we can PM - I can do that all day
Hmm. This one has really brought the worms out of the woodwork.
You guys who understand electronics need to learn to recognise posters who are inaccessible to reason. You don't attempt to give them the benefit of your expertise. You give them the brush-off.
If it looks like somebody who is otherwise accessible to reason is about to be taken in, then there's some reason for intervening, but you have to be careful. There are lots of people out there for whom someone who's obviously fairly well sorted out acts like a magnet.
'Oh, look. There's a person over there who's not totally ****ed up. Maybe they can sort me out.'
So they come over and present their symptoms.
You can't blame them really, you can only pity them.
Ho hum. Another day, another dollar. Leave your contributions in the bowl by the door.
You guys who understand electronics need to learn to recognise posters who are inaccessible to reason. You don't attempt to give them the benefit of your expertise. You give them the brush-off.
If it looks like somebody who is otherwise accessible to reason is about to be taken in, then there's some reason for intervening, but you have to be careful. There are lots of people out there for whom someone who's obviously fairly well sorted out acts like a magnet.
'Oh, look. There's a person over there who's not totally ****ed up. Maybe they can sort me out.'
So they come over and present their symptoms.
You can't blame them really, you can only pity them.
Ho hum. Another day, another dollar. Leave your contributions in the bowl by the door.
Its simply a matter of language, ( no wonder indigenous people have been exploited century after century ) and sharing and conversing politely in same terms.
I use my ears, you use a visual screen. I don't currently have the software, yet you are not polite enough to breadboard and listen.
It goes like this, the visual sense ( a simulation ) shows a result - and is arguably a complete hoax as it is impossible to access Channel A different to Channel B V+ and V- rail, in a Dual op amp as they are inherently tied together in the same casework, yet the simulation quite wrongly ( naughty national instruments for not programming a no go situation ) shows an impossible demonstration that cannot exist ,... because it is visual, it is believed. What next...
Meanwhile no comments from people who trust their ears, and are not fooled by visual gimmicks.
Cheers / Chris
I use my ears, you use a visual screen. I don't currently have the software, yet you are not polite enough to breadboard and listen.
It goes like this, the visual sense ( a simulation ) shows a result - and is arguably a complete hoax as it is impossible to access Channel A different to Channel B V+ and V- rail, in a Dual op amp as they are inherently tied together in the same casework, yet the simulation quite wrongly ( naughty national instruments for not programming a no go situation ) shows an impossible demonstration that cannot exist ,... because it is visual, it is believed. What next...
Meanwhile no comments from people who trust their ears, and are not fooled by visual gimmicks.
Cheers / Chris
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Chris, U1 and U2 are separate devices. If you want to make your comments stick, be careful. 🙂
Thanks Ian, U1 and U2 are op amp 1 and op amp two of a Dual Package AD826, there is only one voltage supply pin labeled V+ and one voltage supply pin labeled V- Yet the simulation shows somehow ability to access each for each channel, which is quite wrong.
Whereas two singles like two AD825's have V+ x2 and V- x2 ... see the difference ? 🙂
Whereas two singles like two AD825's have V+ x2 and V- x2 ... see the difference ? 🙂
I have a homebrew preamp from this millennium and it uses linear 12AX7 vacuum tubes and a minimal amount of negative feedback. OpAmps, weather from this millennium or the last have inherent nonlinearity, finite BW, and massive amounts of negative feedback. For listening to music opamps are still garbage in this millennium or the last.
Don
U1 or U2?
No Chris, U1A and U2A right? These are the same identity chip on different substrates and in different packages. Otherwise you would call them U1A and U1B to fit your description. Look at any verifiable schematic here on DIY even to check this convention.
The U is like any part symbel, R,C,Q etc and the numeral is the I.D. of the individual package, with A-Z being each functional block of that component. Thus U1 and U2 are different devices, Magic Box has merely used that model which was probably the one most available or known reliable. Fooled? Yeah, I was fooled by misreading micro for nano symbols. No excuse to look for a gun to shoot the messenger, though.
If you want to guess about unused devices on each chip, you will have to substantiate that with your own tests, since it will be extremely unlikely that interaction occurs at the level suggested or they would be junk before manufacture even.
No Chris, U1A and U2A right? These are the same identity chip on different substrates and in different packages. Otherwise you would call them U1A and U1B to fit your description. Look at any verifiable schematic here on DIY even to check this convention.
The U is like any part symbel, R,C,Q etc and the numeral is the I.D. of the individual package, with A-Z being each functional block of that component. Thus U1 and U2 are different devices, Magic Box has merely used that model which was probably the one most available or known reliable. Fooled? Yeah, I was fooled by misreading micro for nano symbols. No excuse to look for a gun to shoot the messenger, though.
If you want to guess about unused devices on each chip, you will have to substantiate that with your own tests, since it will be extremely unlikely that interaction occurs at the level suggested or they would be junk before manufacture even.
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Hi Don
... but op amps can be made very nice indeed. Companding is entirely necessary in audio akin to DBX Type 1 , Its this little step the digital CD fraternity needs to take to start getting back to music.
Cheers / Chris
... but op amps can be made very nice indeed. Companding is entirely necessary in audio akin to DBX Type 1 , Its this little step the digital CD fraternity needs to take to start getting back to music.
Cheers / Chris
Hi Ian Why not use single op amps ? avoiding the many issues of such fine print, and clarification. A simple labeling error might equally explain that only one dual was being simulated.
AD826 | Low Cost, High Speed, Low Power Dual Operational Amplifier | High Supply Voltage Amplifiers (>=+12V) | Precision Op Amps (< 50 MHz) | Analog Devices
And none of this simulation, explains the much better sound a transistor connected op amp has. In total contrast Quad with their 405 argued for years that it measured perfectly when anyone who listened knew it sounded very much less so. Meaning ears are always the final qualifier... and to listen is to know.. and in this case this simple idea, is great for audio.
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IMO trying this in a simulator is a waste of time. Manufacturers' Spice models of discrete semiconductors are bad enough. I wouldn't expect their chip models to be any more accurate.
Hi CBBD.
I see you take offence Im Sorry MAn. That post had little or nothing to do with you. This was a little private joust between me and DF. Now you also deffend the use of circuit simulation> Have another read i have not attacked the use of it . In fact i think it is an awsome tool. I also understand that having a physical working circuit will provide real world data to input back into the simulation,. Now we are getting there . Think of it like feed back. open the loop and hey you know what i mean. (can still sound good too) Now to put this tiny circuit together is hardley time consuming or expensive.Now we can add aural sensors to the feedback loop too. ureka we are there . At first this sounds like a great idea . But them there aural sensors i talk about have a very complex cpu and decoding system . However the cpu has many tasks to undertake it offen gets confused and data from other sensors influence the cpu and the data is modified .The thing is, we are trying to please our cpu like i say it is a complex and intersting thing and more offen than not will please itself . What shape are your audio receptors do they make a diffrence to the harmonic structure we hear.. I THINK SO LOL.
LiSTEN TOO IT Man. I have a 3D model of the perfect aural receptor shape. It will be available in three diffrent sizes also in the range will be super version with exagerated dimensions to please those who like it super loud. Also offered is a bespoke service so we can taylor make and adjust it perfectly to ensure you hear what you want to hear. Anyone want to do a group buy on this .
Ian The MAD Tecchy
Ps if anyone would like a copy of the DXG file of the 3D model drop me a pm..................
MERRY CHRISTMAS ............................
Yes Chris, listening is sure the final destination but it is an individual experience and professionals are wise to avoid embroilment in individual tastes, which are a lot more diverse than you may credit. My experience is that only small groups band together over single issue tweaks as there are thousands of possibilities and many more in the Quad upgrade fraternity. It will be difficult to gain particular attention with ubiquitous appeals like "just listen with your ears".
After all, there is a huge chunk of DIY guys who wouldn't touch op-amps with a barge-pole. Of course, it's OK if you don't see the mass of 'em in your media player or the original recording equipment but what we don't see can't hurt us, right? 😉
You won't find full explanations staring at simple sinusoidal 'scope graphs but you do see the plot of the difference to the unthrottled supply result. Surely logic then spells it out that this is the signature of the psycho-acoustic message you experience, albeit with the emphasis of an HF example. Similar will recur with all such signal threshold-crossings, not just occasionally as the simple sine wave suggests. At 1000:1 magnification, its only a small difference, but stereo detail is quite tiny and easily missed too. In a nutshell -it adds harmonic distortion but it will depend on the level of the signal. as to how much and I believe, what harmonics are evident.
A free scope program for your PC will illustrate what is happening when you arrange it for differential measurement at midrange audio frequencies. This is sure cheap and if you have a decent 24 bit sound card, should make a great audio scope so that you can see and record results.
You will at least know more clearly what is happening with tweaks and perception. You'll also be some way ahead of the simulators who predict with models rather than witness reality. Easier, of course but no check on your workmanship or actual parts! 😀
After all, there is a huge chunk of DIY guys who wouldn't touch op-amps with a barge-pole. Of course, it's OK if you don't see the mass of 'em in your media player or the original recording equipment but what we don't see can't hurt us, right? 😉
You won't find full explanations staring at simple sinusoidal 'scope graphs but you do see the plot of the difference to the unthrottled supply result. Surely logic then spells it out that this is the signature of the psycho-acoustic message you experience, albeit with the emphasis of an HF example. Similar will recur with all such signal threshold-crossings, not just occasionally as the simple sine wave suggests. At 1000:1 magnification, its only a small difference, but stereo detail is quite tiny and easily missed too. In a nutshell -it adds harmonic distortion but it will depend on the level of the signal. as to how much and I believe, what harmonics are evident.
A free scope program for your PC will illustrate what is happening when you arrange it for differential measurement at midrange audio frequencies. This is sure cheap and if you have a decent 24 bit sound card, should make a great audio scope so that you can see and record results.
You will at least know more clearly what is happening with tweaks and perception. You'll also be some way ahead of the simulators who predict with models rather than witness reality. Easier, of course but no check on your workmanship or actual parts! 😀
Chris, could you describe "how" it does make better the sound? It sounds more 'sharp', more 'contrast' ?
Sound using stereo ( Alan Blumein 1931 lodged patent ) occupies the left and right channel, its effect is to portray recorded music toward realism. Therefore stereo reproduction in my opinion has a high level of importance to portray music towards realism. It is a key factor to discern if electronics involved in its proper reproduction is capable or incapable.
Here are some ideas that fail totally in this area SPDIF , MP3
Here are some that totally succeed. DBX Type 1, Companding, FLAC WAV, LDR Preamps DBX 700, connecting LRCK,DATA BCK independently via 74HC74, to link to DAC ( C.Daly Electronics World June 1997 )
Here are some that gets close, Ogg Vorbis, Linn Sondek,
The simple use of transistors biased at approx 6ma across a transistor applied to opamp power supplies in a stereo installation instantly gets stereo correct. To describe accurately the sound stage has added dimension over a non transistor applied op amp. Sounds instead of spreading from the middle have space of their own.
I have been very fortunate in life to have lived with some amazing equipment including Quad ESL57, and I have good knowledge of sound.
As a result there is the ability with transistors provided this way to hear more, which includes better bass reproduction and with better clarity.
The equipment I have used for this opinion is primarily a Marantz CD80 TDA1541 with AD825 singles all with transistor improvement to power supply, also one AD825 dual with transistor improvement. I am connecting AOL AOR linking to final opamp via 22k resistor to tie first opamp to final within negative feedback. ( Forum contribution http://www.diyaudio.com/forums/digital-source/92994-marantz-cd50-mod-just-stunning.html )
Cheers / Chris
Here are some ideas that fail totally in this area SPDIF , MP3
Here are some that totally succeed. DBX Type 1, Companding, FLAC WAV, LDR Preamps DBX 700, connecting LRCK,DATA BCK independently via 74HC74, to link to DAC ( C.Daly Electronics World June 1997 )
Here are some that gets close, Ogg Vorbis, Linn Sondek,
The simple use of transistors biased at approx 6ma across a transistor applied to opamp power supplies in a stereo installation instantly gets stereo correct. To describe accurately the sound stage has added dimension over a non transistor applied op amp. Sounds instead of spreading from the middle have space of their own.
I have been very fortunate in life to have lived with some amazing equipment including Quad ESL57, and I have good knowledge of sound.
As a result there is the ability with transistors provided this way to hear more, which includes better bass reproduction and with better clarity.
The equipment I have used for this opinion is primarily a Marantz CD80 TDA1541 with AD825 singles all with transistor improvement to power supply, also one AD825 dual with transistor improvement. I am connecting AOL AOR linking to final opamp via 22k resistor to tie first opamp to final within negative feedback. ( Forum contribution http://www.diyaudio.com/forums/digital-source/92994-marantz-cd50-mod-just-stunning.html )
Cheers / Chris
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Here is a nice little calculator for -db to THD calculation. For those still following this thread. An AD826 stated within its datasheet http://www.analog.com/en/precision-...oltage-amplifiers/ad826/products/product.html used in the simulation has itself a stated THD of -78b THD to dB - convert percent to decibels dB and dB decibels to percentage percent voltage % vs per cent converter THD+N distortions calculation signal distortion factor attenuation in dB to distortion factor k in percent decibel damping - sengpielaudi
Cheers / Chris
Cheers / Chris
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Yeah, let's talk about that. Stereo. The human's hearing is a pretty crafty device. It is so sensitive that you can accurately determine the location of the sound's origins. A dropping coin, you'll know eactly where it dropped just by listening.
But well, how is that accomplished? It takes some time for the sound pressure wave to reach your ears. Eventhough the distance between the ears is relatively small, the ears will notice a delay if the soundwave hits one ear the first. It's minuscule but that's how it works. When both ears are invoked by the soundwave at the same time, it must have come from the front or back. So simply put: phase difference between the L and R channel primarily determine the position in the sound stage.
With the transistored opamp circuit, phaseshift only starts occurring at around 1MHz, noticable at 10MHz and beyond - but that's the domain of an opamp's regulation frequency, the max GBP for a given gain. The simulation does not show active phase modulation in the audio band. This says that it does not tamper with the stereo image of the L and R related analog channel information (phase shift of instrument fundamentals, simulating 'hitting our ears at a different angle'). What it does is that it introduces spiking at the crossover region which may result in 'sharp', 'cantrastious', fatiguing highs. This happens to both channels if you did the mod to both channels. Perhaps the distortion removes/cancels with the signal in the center of the soundstage, affecting the instruments who got partially altered.
There is no magic to audio, everything has a measurable reason. Problem is coming up with methods that reliably link the science to our perception. Acknowledging the science behind it is a start and likewise, acknowledge the multitudes of perception. But there must be big common denominators, after all the audio field has quite the vocabulary to describe sound 😉
But well, how is that accomplished? It takes some time for the sound pressure wave to reach your ears. Eventhough the distance between the ears is relatively small, the ears will notice a delay if the soundwave hits one ear the first. It's minuscule but that's how it works. When both ears are invoked by the soundwave at the same time, it must have come from the front or back. So simply put: phase difference between the L and R channel primarily determine the position in the sound stage.
With the transistored opamp circuit, phaseshift only starts occurring at around 1MHz, noticable at 10MHz and beyond - but that's the domain of an opamp's regulation frequency, the max GBP for a given gain. The simulation does not show active phase modulation in the audio band. This says that it does not tamper with the stereo image of the L and R related analog channel information (phase shift of instrument fundamentals, simulating 'hitting our ears at a different angle'). What it does is that it introduces spiking at the crossover region which may result in 'sharp', 'cantrastious', fatiguing highs. This happens to both channels if you did the mod to both channels. Perhaps the distortion removes/cancels with the signal in the center of the soundstage, affecting the instruments who got partially altered.
There is no magic to audio, everything has a measurable reason. Problem is coming up with methods that reliably link the science to our perception. Acknowledging the science behind it is a start and likewise, acknowledge the multitudes of perception. But there must be big common denominators, after all the audio field has quite the vocabulary to describe sound 😉
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So an AD826 has a quoted THD of -78db = 0.01258 , the simulation shows 0.013 is this any co-incidence ?
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