I wonder what they call emitter follower in tube language: Grid Follower?
Fairly obviously, cathode follower.
Nothing really to discuss, as your entire premise is completely untrue - valves are considerably noisier than solid state, and also don't give 'huge power', transistors give far greater powers at a tiny fraction of the cost. The low efficiency of valve amps (always lower than 50%) means you can't get high powers when fed from normal mains sockets.
Valves are used by some musicians (mostly guitarists) because they want the high distortion and high noise you get from valves - as part of their desired 'sound'.
The tube circuit corresponding to emitter follower is called a cathode follower.
If you want to learn how tubes work, download and read the Radiotron Designer's Handbook (4th edition). The RDH covers tube electronics from the power supply, through audio, and into radio frequencies. ANything you want to know is there. Here is one place to download it from:
RDH4 mirror
And go to the tubes section of this forum, and in the "sticky" section at the top is a resource thread titled Online Tube Learning. Look through that material.
I am not sure why you think tubes cannot work at high frequencies. Radios work at high frequencies, and there are plenty of tube radios. SHort wave radios. Microwave radios. FM radios operate at 100MHz and higher. TV sets to hundreds of MHz. World War 2 era aircraft had radio communication equipment all tube based. Radar sets were tubes. To this day many high power radio transmitters use vacuum tubes.
If you want to learn how tubes work, download and read the Radiotron Designer's Handbook (4th edition). The RDH covers tube electronics from the power supply, through audio, and into radio frequencies. ANything you want to know is there. Here is one place to download it from:
RDH4 mirror
And go to the tubes section of this forum, and in the "sticky" section at the top is a resource thread titled Online Tube Learning. Look through that material.
I am not sure why you think tubes cannot work at high frequencies. Radios work at high frequencies, and there are plenty of tube radios. SHort wave radios. Microwave radios. FM radios operate at 100MHz and higher. TV sets to hundreds of MHz. World War 2 era aircraft had radio communication equipment all tube based. Radar sets were tubes. To this day many high power radio transmitters use vacuum tubes.
Mixed the joke up. How do they call common base, then? Common Gril?
In case valves were noisier, they wouldn't have used them for high quality noiseless sound.
In case they don't give high power (though lower efficiency), why do they use them (now or until recently) for high power radio and TV transmission?
The point for high radio and locator / radar frequency is taken. Most tube lovers claim the tubes give strong base but not very strong treble. I have personally experienced so but I am not very good in the musical field, so I do not know whether the tubes cannot perform well or I cannot hear well. I hear the transistor frequency but there mey be something wrong with the way I hear in general.
The guitarists who use valves claim they use them because of the clear and warm sound. And lack of distortions, good linearity.
Valves do NOT have self induced noise. There is no where the noise would come from. Vaccuum? Soldering points and high temperature give very tiny undetectable or no noise at all.
Isn't it possible to use increasing (step up) transformers: higher voltage lower current, than the mains.
Power transistors HAVE BEEN more expensive than tubes. NOW they ARE NOT.
There is nothing wrong to differ in oppinion. However, I believe you want to ridicule and post the other way around. In case of so, still OK. May be funny. Otherwise, anyone can say what they want.
In case valves were noisier, they wouldn't have used them for high quality noiseless sound.
In case they don't give high power (though lower efficiency), why do they use them (now or until recently) for high power radio and TV transmission?
The point for high radio and locator / radar frequency is taken. Most tube lovers claim the tubes give strong base but not very strong treble. I have personally experienced so but I am not very good in the musical field, so I do not know whether the tubes cannot perform well or I cannot hear well. I hear the transistor frequency but there mey be something wrong with the way I hear in general.
The guitarists who use valves claim they use them because of the clear and warm sound. And lack of distortions, good linearity.
Valves do NOT have self induced noise. There is no where the noise would come from. Vaccuum? Soldering points and high temperature give very tiny undetectable or no noise at all.
Isn't it possible to use increasing (step up) transformers: higher voltage lower current, than the mains.
Power transistors HAVE BEEN more expensive than tubes. NOW they ARE NOT.
There is nothing wrong to differ in oppinion. However, I believe you want to ridicule and post the other way around. In case of so, still OK. May be funny. Otherwise, anyone can say what they want.
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Point taken. Make sense to travel fast in vaccuum too. There is 0 resistance, one the other hand. Cannot understand why would tube sound base and not very treble.
Thanks for the book. May read in a far future. I am not sure I would remember what I have read and I am not able to purchase tubes because they are not sold in the general stores, so, I cannot make anything with tubes now.
I have never heard of Radiotron but I have thought there may be one or very few manufacturers of tubes still around. I meant to say there isn't enough and I doubt they do research and improve the tubes further (in case possible). But they may. I am 99% sure there would have been stronger improvement in case of higher consumption or lack of alternative.
Again, I have just read the point for high frequencies again. Point taken. I screwed the thinking up. When there is an engineering point, there is an engineering point.
I am trying to think whether there isn't any base/treble trade off. In other words: limited frequency range of performance. I would say no, because the audio range is very tiny: just ~100 (20 to ~20*100).
Thanks for the book. May read in a far future. I am not sure I would remember what I have read and I am not able to purchase tubes because they are not sold in the general stores, so, I cannot make anything with tubes now.
I have never heard of Radiotron but I have thought there may be one or very few manufacturers of tubes still around. I meant to say there isn't enough and I doubt they do research and improve the tubes further (in case possible). But they may. I am 99% sure there would have been stronger improvement in case of higher consumption or lack of alternative.
Again, I have just read the point for high frequencies again. Point taken. I screwed the thinking up. When there is an engineering point, there is an engineering point.
I am trying to think whether there isn't any base/treble trade off. In other words: limited frequency range of performance. I would say no, because the audio range is very tiny: just ~100 (20 to ~20*100).
Mixed the joke up. How do they call common base, then? Common Gril?
Yes, common grid - the transistor terms are all derived from the valve ones.
They are noisier, and they don't use them for 'high quality noiseless sound' (which is a pretty meaningless term). Can you give any such example of what you might mean?.
They don't really - they used 'vacuum type devices' for high power radio and TV transmitters, but not standard valves/tubes. Magnetrons and travelling wave tubes are two examples of related vacuum devices.
It took a good number of years to manufacture transistor RF transmitters of similar power, and similar (and in fact now better) reliability.
Neither bass nor treble are as good as transistor amps, limitations in output transformers are the main reasons.
They can claim what they like, but it's completely untrue - valves give high distortion, poor frequency response, poor linearity etc.
It's the reduction in quality that they like, the term 'warm' even describes changes to the original sound, which is a distortion of the original.
I come from the valve days, and still service valve equipment, valves are far noisier than transistors - which is why you don't use valves in noise sensitive applications.
If you listen to old recordings, you can often hear the noise from the valve mixers used to make the recordings.
The power is still the same, limited to just over 3000W in the UK, far less in the USA. Valve amps obviously use transformers anyway, because you need voltages well above even UK mains for valve amps - with some amps needing a LOT higher.
Not for a VERY, VERY long time.
But valves were effectively obselete back in the 70's/80's, it's only really guitarists that have kept them going at all.
I'm sorry, but you seem to have little knowledge of electronics, or physics in general - even claiming audio was digital not analogue further back in this thread.
On the valves, I said what I had to say and I stay behind everything which I haven't been proven otherwise. For example, I was proven otherwise on the frequency response by Enzo and I immediately took the point and admitted the mistake. I should have thought this way but I didn't.
On the "sound is digital" statement I made an expression. A saying. A self made proverb. I do not know how to explain. Any linguist here, please do. What I said in an expression way is: "Digital sound is the best and the most important thing in sound engineering. Everything must be digital wherever possible." A bit pathetic and simple and basic and obvious but I like digital a lot. Too bad people cannot emit digital signals when they talk. Then everything was to be digital. Too bad people cannot hear digital. Otherwise everything was to be digital.
On the common grid and "grid follower" the joke was with the word grid: grid is very similar to grill in what these are and the sounding. One can put a metal grid on top of charcoal and use this as a grill. Hence, I thought, would be a funny thing to say. Also, a jail cell looks like having a grid to prevent the prisoners to escape. Hence, the joke becomes even funnier.
I respect your experience with valves. However, there are other people who have had similar experience with valves and say their oppinions too. I am not one of these people.
Tubes in general sound I have seen: 1992 to 1994, Shop "Sound with Style", Sheffield, England, UK. Now: Shop "Bay Bloor Radio", Toronto, Ontario, Canada.
On the "sound is digital" statement I made an expression. A saying. A self made proverb. I do not know how to explain. Any linguist here, please do. What I said in an expression way is: "Digital sound is the best and the most important thing in sound engineering. Everything must be digital wherever possible." A bit pathetic and simple and basic and obvious but I like digital a lot. Too bad people cannot emit digital signals when they talk. Then everything was to be digital. Too bad people cannot hear digital. Otherwise everything was to be digital.
On the common grid and "grid follower" the joke was with the word grid: grid is very similar to grill in what these are and the sounding. One can put a metal grid on top of charcoal and use this as a grill. Hence, I thought, would be a funny thing to say. Also, a jail cell looks like having a grid to prevent the prisoners to escape. Hence, the joke becomes even funnier.
I respect your experience with valves. However, there are other people who have had similar experience with valves and say their oppinions too. I am not one of these people.
Tubes in general sound I have seen: 1992 to 1994, Shop "Sound with Style", Sheffield, England, UK. Now: Shop "Bay Bloor Radio", Toronto, Ontario, Canada.
Personally I am not ''for'' or ''against'' digital or analog. To me they both have their place in the music world, and both are a means to an end. As for the Les Paul with a $4000 price tag and digital output, well I won't be the first one in line to buy it. It is a technology that seems new, but like you said these things have a way of dropping rapidly in price as time goes on. Not so for a vintage LP which could easily increase in price despite its old technology.
Your ideas for direct-to-digital guitar are approachable from a DIY standpoint. If you have a general idea of what you want to output as far as digital standards go (MIDI? USB? etc..), it is possible to design your own transducer/pickup, and with ADCs and interface run from there. If you are good in the software side, that is where there is a lot of potential ..there are a lot of off the shelf programs that work on PC for amp sim etc..and maybe you would come up with something even more interesting. Have a look at Ghost pickup systems by graphtech, and also Variax guitars by Line 6..these are more cost effective to start, and may inspire you.
Your ideas for direct-to-digital guitar are approachable from a DIY standpoint. If you have a general idea of what you want to output as far as digital standards go (MIDI? USB? etc..), it is possible to design your own transducer/pickup, and with ADCs and interface run from there. If you are good in the software side, that is where there is a lot of potential ..there are a lot of off the shelf programs that work on PC for amp sim etc..and maybe you would come up with something even more interesting. Have a look at Ghost pickup systems by graphtech, and also Variax guitars by Line 6..these are more cost effective to start, and may inspire you.
The digital vs analog catch 22
My 2 cents: Other than a non amplified performance that you attend live, all other amplified live sound and recording of any music or sound is only a reproduction (digital, analog or mix) of the original performance. The voice is analog, as is guitar and other acoustic instruments.
In an acoustic guitar the air pressure that varies causing sound to come out of the sound hole, is derived from physical vibration of strings and body resonance in an acoustic guitar chamber : it is ''analog amplification''. Electric guitar traditionally used magnetic coils as the transducer, but piezo types pickup the string vibration directly at the bridge. To me they both have their strengths and weakness. A laser could be used to pick up that vibration, I am sure.. but you will still get noise.
So going from an analog sound source through any transducer and then to digital conversion must by definition introduce some noise, be it thermal, electromagnetic, or digital conversion/quantization error (yes more noise). Same goes for converting it back to analog sound.
My 2 cents: Other than a non amplified performance that you attend live, all other amplified live sound and recording of any music or sound is only a reproduction (digital, analog or mix) of the original performance. The voice is analog, as is guitar and other acoustic instruments.
In an acoustic guitar the air pressure that varies causing sound to come out of the sound hole, is derived from physical vibration of strings and body resonance in an acoustic guitar chamber : it is ''analog amplification''. Electric guitar traditionally used magnetic coils as the transducer, but piezo types pickup the string vibration directly at the bridge. To me they both have their strengths and weakness. A laser could be used to pick up that vibration, I am sure.. but you will still get noise.
So going from an analog sound source through any transducer and then to digital conversion must by definition introduce some noise, be it thermal, electromagnetic, or digital conversion/quantization error (yes more noise). Same goes for converting it back to analog sound.
The error of digitisation/quantatisation appears only once: at the ADC.
The DAC would use the number th recover the signal from the number and, assuming the DAC is perfect (just quantatisation, no other errors, noise, etcetera, no "analogue noise") the signal will be recovered perfectly from this number. Whether the number is true or with an error depends ONLY on the ADC. There always be an error but this error is negligible. Mainly as compared to the non linear distortions and the electromagnetic noise of the analogue systems, as well as their self induced noise.
Tubes are perfect BUT, from the non signal point of view, I have some doubts as far as the electromagnetic succeptance goes because they stick high above the PCB and look like antennas to the noise. Designers would stick them up even higher for a better cooling with almost no EMI protection. Some would put a metal "fence" for mechanical stability, mainly, and would ground this to get whatever shielding effect they can. Not much. Some sources state they make metal encapsulated tubes, which is great but these can't be cooled so well.
The guitar is not a problem. Working with the hum bucker (pick up coil) is easy, so is digitising this. The microphone may be more tricky. They do them, though, not sure what the quality is. Never seen one in the local general purpose stores for home electronics.
MAKE A PERFECT MICROPHONE WITH A PERFECT DIGITISATION AND YOU WILL NOT HAVE AS MUCH NOISE AS ANALOGUE. The question is how good this microphone can be. The other question is whether anyone else except Celine Dion can afford this at the beginning. When the price is very high at the beginning, as with Gibson, people may decide not to switch to this item even in their desires and the item will not become popular thus the company may not do the item nor drop the prices and may discontinue the item concentrating only one money making popular items. Thus, a better design doesn't go through.
WHETHER 2C OR 2 MILLION DOLLAR TALK, DIGITAL IS ALWAYS BETTER THAN ANALOGUE FOR ANY SOUND THE MOST. SOUND PROCESSING IS THE VERY BASIC ELECTRONICS ENGINEERING. No one can change this and this has been found many years ago and is applied elsewhere. I am not interested in talking for something where there are others who have been talking for years and proven their points even with prices and industry against them at the beginning. THE ONLY AREA where there is still heavy application of analogue is in concert sound and, probably, still in some studio sound. Therefore, I would like to concentrate on this fields and get rid of analogue as much as possible in this fields too.
I didn't want but some of you push into phylosophical discussions as to whether the world and the sound are analogue or digital. These discussions are irrelevant to the topic because even if assumed analogue, there is nothing wrong to digitise the sound and then to convert the sound back to analogue (when necessary) JUST because this way is better. Who cares whether sound is analogue or digital when this way is better.
If you are so much interested in physophy, contact your local Physics phylosopher. Phylosophy departments are divided into groups one of which is phylosophy of physics.
Before so, you may as well wish to think this way: if Ainstain is right (which is not given) light is digital to a great deal of extend. Pushing air may as well prove to be digital at atom and electron level, most certainly at molecular. This is not important though.
Sound is digital, just we human can't do sound: means everything with sound must be digital. Humans MUST emit digital sound. Digital is better. They cannot. I don't care. I said MUST I did not say CAN. This is a saying and a proverb meaning everything with sound must be digital. When not possible, do whatever you do only where not possible.
Although, fully digital sound even when impossible was done a few hundred years ago although impossible still done: Beethoven had acquired a great deal of analogue music experience. Then Beethoven became deaf because of whatever reason (make jokes here yourseves). When Beethoven was deaf, Beethoven was presented by music written by other composers in DIGITAL FORMAT. Beethoven took this digital format and did NOT convert this to analogue: processed the sound from source to user perfectly in ONLY DIGITAL based on the previous analogue experience. When Beethoven composed, Beethoven started in digital format based on previous analogue experience. Did not start in analogue and then converted. Started from digital. Then the music was given to other composers and conductors who did NOT convert to analogue (at the beginning) but, based on their previous analogue experience, got the SOUND in fully digital format. THE CONVERSION WAS CARRIED OUT FOR THOSE WHO WERE UNABLE TO DO SO AS WELL AS FOR FUN, ENTERTAINMENT AND BETTER PERCEPTION (WHICH DOESN'T MEAN BETTER SOUND).
Just to be clear: SHIELDING DOES NOT MEAN NOISE ELEMINATION BUT NOISE REDUCTION and this reduction is far away from good. DIGITAL IS NOT 100% NOISE PROOF BUT PRETTY CLOSE. Still, fully digital (immediately after the source in non Beethoven terms) does not mean noise elimination but noise reduction which is pretty good but not perfect.
I think there is a problem with this discussion: most believe shielding stops or reduces the noise below significant amounts. I do NOT. Hence, there is no way to accept analogue as a better option. Also, some say digital is more noisy than analogue. I do NOT. However, digital is not without noise either. The question is which one is LESS noisy. I say DIGITAL. The rest of the world say: DIGITAL except for microphones. Guitar manufacturers cannot talk and they say nothing. They communicate with solos.
ANALOGUE DOESN'T WORK ANY MORE IN ANY FIELD OF SOUND. SORRY. REASONS: MORE NOISE, MORE DISTORTION, LOUSY FILTERING AND, IN SOME CASES, lousy bandwith.
The discussion was to get the last of the mochicans: THE MICROPHONE and the guitar FULLY digital. Please, stop bsing on origin of noise. They do this but they do not use this except one or a few. The trick is everyone to use digital microphones ONLY or MAINLY. The so called USB Microphones.
Enough. I need to go see the dinasaurs. Not the tubes. Anything analogue is dinasaur. Please, do not insult the dinasaurs, they are very good animals. The tubes are the funniest of them all.
I wonder whether you would put a sinthesiser to a convertor after the synthesiser and a preamplifier and then put the signal to the mixer or wherever. What apreposterous irony. A digital device gets analogised then gets digitised again to be analogised again to be listened to off of a CD or wahtever storage media. Looks and sounds like a PC monitor witha VGA input!
The DAC would use the number th recover the signal from the number and, assuming the DAC is perfect (just quantatisation, no other errors, noise, etcetera, no "analogue noise") the signal will be recovered perfectly from this number. Whether the number is true or with an error depends ONLY on the ADC. There always be an error but this error is negligible. Mainly as compared to the non linear distortions and the electromagnetic noise of the analogue systems, as well as their self induced noise.
Tubes are perfect BUT, from the non signal point of view, I have some doubts as far as the electromagnetic succeptance goes because they stick high above the PCB and look like antennas to the noise. Designers would stick them up even higher for a better cooling with almost no EMI protection. Some would put a metal "fence" for mechanical stability, mainly, and would ground this to get whatever shielding effect they can. Not much. Some sources state they make metal encapsulated tubes, which is great but these can't be cooled so well.
The guitar is not a problem. Working with the hum bucker (pick up coil) is easy, so is digitising this. The microphone may be more tricky. They do them, though, not sure what the quality is. Never seen one in the local general purpose stores for home electronics.
MAKE A PERFECT MICROPHONE WITH A PERFECT DIGITISATION AND YOU WILL NOT HAVE AS MUCH NOISE AS ANALOGUE. The question is how good this microphone can be. The other question is whether anyone else except Celine Dion can afford this at the beginning. When the price is very high at the beginning, as with Gibson, people may decide not to switch to this item even in their desires and the item will not become popular thus the company may not do the item nor drop the prices and may discontinue the item concentrating only one money making popular items. Thus, a better design doesn't go through.
WHETHER 2C OR 2 MILLION DOLLAR TALK, DIGITAL IS ALWAYS BETTER THAN ANALOGUE FOR ANY SOUND THE MOST. SOUND PROCESSING IS THE VERY BASIC ELECTRONICS ENGINEERING. No one can change this and this has been found many years ago and is applied elsewhere. I am not interested in talking for something where there are others who have been talking for years and proven their points even with prices and industry against them at the beginning. THE ONLY AREA where there is still heavy application of analogue is in concert sound and, probably, still in some studio sound. Therefore, I would like to concentrate on this fields and get rid of analogue as much as possible in this fields too.
I didn't want but some of you push into phylosophical discussions as to whether the world and the sound are analogue or digital. These discussions are irrelevant to the topic because even if assumed analogue, there is nothing wrong to digitise the sound and then to convert the sound back to analogue (when necessary) JUST because this way is better. Who cares whether sound is analogue or digital when this way is better.
If you are so much interested in physophy, contact your local Physics phylosopher. Phylosophy departments are divided into groups one of which is phylosophy of physics.
Before so, you may as well wish to think this way: if Ainstain is right (which is not given) light is digital to a great deal of extend. Pushing air may as well prove to be digital at atom and electron level, most certainly at molecular. This is not important though.
Sound is digital, just we human can't do sound: means everything with sound must be digital. Humans MUST emit digital sound. Digital is better. They cannot. I don't care. I said MUST I did not say CAN. This is a saying and a proverb meaning everything with sound must be digital. When not possible, do whatever you do only where not possible.
Although, fully digital sound even when impossible was done a few hundred years ago although impossible still done: Beethoven had acquired a great deal of analogue music experience. Then Beethoven became deaf because of whatever reason (make jokes here yourseves). When Beethoven was deaf, Beethoven was presented by music written by other composers in DIGITAL FORMAT. Beethoven took this digital format and did NOT convert this to analogue: processed the sound from source to user perfectly in ONLY DIGITAL based on the previous analogue experience. When Beethoven composed, Beethoven started in digital format based on previous analogue experience. Did not start in analogue and then converted. Started from digital. Then the music was given to other composers and conductors who did NOT convert to analogue (at the beginning) but, based on their previous analogue experience, got the SOUND in fully digital format. THE CONVERSION WAS CARRIED OUT FOR THOSE WHO WERE UNABLE TO DO SO AS WELL AS FOR FUN, ENTERTAINMENT AND BETTER PERCEPTION (WHICH DOESN'T MEAN BETTER SOUND).
Just to be clear: SHIELDING DOES NOT MEAN NOISE ELEMINATION BUT NOISE REDUCTION and this reduction is far away from good. DIGITAL IS NOT 100% NOISE PROOF BUT PRETTY CLOSE. Still, fully digital (immediately after the source in non Beethoven terms) does not mean noise elimination but noise reduction which is pretty good but not perfect.
I think there is a problem with this discussion: most believe shielding stops or reduces the noise below significant amounts. I do NOT. Hence, there is no way to accept analogue as a better option. Also, some say digital is more noisy than analogue. I do NOT. However, digital is not without noise either. The question is which one is LESS noisy. I say DIGITAL. The rest of the world say: DIGITAL except for microphones. Guitar manufacturers cannot talk and they say nothing. They communicate with solos.
ANALOGUE DOESN'T WORK ANY MORE IN ANY FIELD OF SOUND. SORRY. REASONS: MORE NOISE, MORE DISTORTION, LOUSY FILTERING AND, IN SOME CASES, lousy bandwith.
The discussion was to get the last of the mochicans: THE MICROPHONE and the guitar FULLY digital. Please, stop bsing on origin of noise. They do this but they do not use this except one or a few. The trick is everyone to use digital microphones ONLY or MAINLY. The so called USB Microphones.
Enough. I need to go see the dinasaurs. Not the tubes. Anything analogue is dinasaur. Please, do not insult the dinasaurs, they are very good animals. The tubes are the funniest of them all.
I wonder whether you would put a sinthesiser to a convertor after the synthesiser and a preamplifier and then put the signal to the mixer or wherever. What apreposterous irony. A digital device gets analogised then gets digitised again to be analogised again to be listened to off of a CD or wahtever storage media. Looks and sounds like a PC monitor witha VGA input!
... and fully analogue sound doesn't have any noise at all. Can I have the 2 cents, please?
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Here's another 2 cents for grabs: There is no philosophy involved about stating the conditions for the ''discussion''. Analog sound waves go through some kind of transducer which will add noise and/or distortion or let's say measurement error. They follow the rules of physics, Yes? The quantization error, (and aliasing error, thermal noise of the ADC reference voltage) of digitization also introduce noise. You eventually have to get back to reproducing the audio wave from the digital world if you want to ever hear it again..and I can't assume there is a DAC that is perfect. It is again governed by the laws of physics. You said digital is better because you are assumed the DAC was perfect. But that is a discussion weighted in favor of the digital world. Not fair man!! OK then for the analog side:
But wait a minute..What about a speaker with perfectly flat signal response and no distortion or phasing errors? And the perfect microphone would have that too, flat response with virtually no EM noise. Actually those microphones do exist and used in acoustic research but awful expensive. They are flat to within +/-0.2 dB, and with the right electronic preamp (ie Charge, not voltage preamp) better than 120 dB signal to noise. ( Your ears don't work as well as what those mics can reproduce for a signal..unless you are a bat!) All done in the analogue world by dinosaur technology from the 60s. Peoples ears are dinosaurs, too. In a lot of cases the digital world is measurably ''better'' for some things, but the analog world seems comfortable on the ears in audio too.
Hey just a weird side thought: Has anyone else ever visited an anechoic chamber in an audio research lab? The total absence of noise and no spacial reference from any echo or reverberations is a downright freaky experience. Your voice stops dead in front of you, very strange on the brain. The real analog world has plenty of background noise, so not having any is kind of unnatural and uncomfortable.
OK that was 4 cents worth..so sue me
But wait a minute..What about a speaker with perfectly flat signal response and no distortion or phasing errors? And the perfect microphone would have that too, flat response with virtually no EM noise. Actually those microphones do exist and used in acoustic research but awful expensive. They are flat to within +/-0.2 dB, and with the right electronic preamp (ie Charge, not voltage preamp) better than 120 dB signal to noise. ( Your ears don't work as well as what those mics can reproduce for a signal..unless you are a bat!) All done in the analogue world by dinosaur technology from the 60s. Peoples ears are dinosaurs, too. In a lot of cases the digital world is measurably ''better'' for some things, but the analog world seems comfortable on the ears in audio too.
Hey just a weird side thought: Has anyone else ever visited an anechoic chamber in an audio research lab? The total absence of noise and no spacial reference from any echo or reverberations is a downright freaky experience. Your voice stops dead in front of you, very strange on the brain. The real analog world has plenty of background noise, so not having any is kind of unnatural and uncomfortable.
OK that was 4 cents worth..so sue me
Yes, there will be problems on the analogue side of the ADC, on the reference voltage. These must be very stable, placed as closed to the ADC and connected to the common point of the source and the reference as close to the ADC as possible. The reference is basically an improved zenner with low internal impedance. The goood ones are very stable but there will always be noise. The main problem, I think, comes from the switching noise. Thermally, the reference voltage is very stable but not perfect.
The DAC is not perfect in other terms than not altering the number and not adding additional error of quantatisation unless there is a change in bitness.
There may be a possibility to achieve a good performance with analogue in special circumstances: totally isolated and shielded laboratories, etcetera. The switching noise cannot be removed in these laboratories, true. Systematically, analogue systems do not have any noise. They would have distortions and, in case of solid state, self noise, mainly increasing with temperature. Cooling the analogue would help in this circumstances. Computer fans and heathsinks are largely available and may be used for the purpose. Car style CPU cooling fans with water radiators too. Oil cooling is also something practiced in high power. Multiple Peltier coolers taking heath away too. Refrigerator elements, liquid Nitrogen, etecetera too.
In a lab, thinks are nice. In the surrounding world, no.
Our ears are used to noise because there isn't any way around. When we listen to music we expect to have noise but there is nothing wrong not to have or to have as little as possible. We can train our ears to switch to "low noise" when we listen to music and to "high noise" when out.
When listening to a CD, there has been one conversion then the other as you pointed out. Is there too much noise on the CD? Distortions? Other problems? Why can we not do this on concert performance? We do not need to do this in a lab, this is true. Analogue all the way as opposed to analogue digital, digital analogue. Same amplification, same input, same output. The only reason, I can think of, for this in a lab is in case we need to do filtering and tricks (adjustment of frequencies, someone hit a wrong note or a bit off, 1/4 tone or less...) but this is cheating.
Top microphone exist but top microphone can be digitised too. Noisy and more circuitry, for the lab. But when there are 100 yards of cabels, jacks, sockets, generators, cars, airplanes, radiation, electric distribution cables, radios, millions of people rubbing rubber soles (good not on carpets) and discharging, high power supply cables, stadium lights, trucks, motorbikes, electrically ignited pyrotechnics, heathers, coolers, refridgerators, electric stoves, 100 laptops, powerfull big screens, etcetera, there may be some point. Yes, there will be a lot of ambient noise anyways. But is there any reason why the not so significant analogue noise shouldn't be removed. What is the price? Less than 4c?
The DAC is not perfect in other terms than not altering the number and not adding additional error of quantatisation unless there is a change in bitness.
There may be a possibility to achieve a good performance with analogue in special circumstances: totally isolated and shielded laboratories, etcetera. The switching noise cannot be removed in these laboratories, true. Systematically, analogue systems do not have any noise. They would have distortions and, in case of solid state, self noise, mainly increasing with temperature. Cooling the analogue would help in this circumstances. Computer fans and heathsinks are largely available and may be used for the purpose. Car style CPU cooling fans with water radiators too. Oil cooling is also something practiced in high power. Multiple Peltier coolers taking heath away too. Refrigerator elements, liquid Nitrogen, etecetera too.
In a lab, thinks are nice. In the surrounding world, no.
Our ears are used to noise because there isn't any way around. When we listen to music we expect to have noise but there is nothing wrong not to have or to have as little as possible. We can train our ears to switch to "low noise" when we listen to music and to "high noise" when out.
When listening to a CD, there has been one conversion then the other as you pointed out. Is there too much noise on the CD? Distortions? Other problems? Why can we not do this on concert performance? We do not need to do this in a lab, this is true. Analogue all the way as opposed to analogue digital, digital analogue. Same amplification, same input, same output. The only reason, I can think of, for this in a lab is in case we need to do filtering and tricks (adjustment of frequencies, someone hit a wrong note or a bit off, 1/4 tone or less...) but this is cheating.
Top microphone exist but top microphone can be digitised too. Noisy and more circuitry, for the lab. But when there are 100 yards of cabels, jacks, sockets, generators, cars, airplanes, radiation, electric distribution cables, radios, millions of people rubbing rubber soles (good not on carpets) and discharging, high power supply cables, stadium lights, trucks, motorbikes, electrically ignited pyrotechnics, heathers, coolers, refridgerators, electric stoves, 100 laptops, powerfull big screens, etcetera, there may be some point. Yes, there will be a lot of ambient noise anyways. But is there any reason why the not so significant analogue noise shouldn't be removed. What is the price? Less than 4c?
Yes I agree and seriously believe that standard commercially sold CD audio format is quite limited..and it is becoming a dinosaur too. Limited capacity and imperfect playback of the CD forced to encode the digital ''pure signal'', involving error correction, compression, oversample techniques etc. Storage and play back is now getting a lot better in terms of pure audio format. Now that other mass digital storage is available at low cost. Even enhanced format CD is a big improvement now. Recording in 24 bit , 32bit 96Khz and up now is pretty standard, so it is getting better. What you can do with home recording on PC now with some good sound conversion is very good. Better than what even a few years ago would cost tens of thousands of dollars. I really hope the industry does evolve the standards of high fidelity digital.. what the masses are appealing to right now with mp3 is really bad(!)
ADC suggestion
Hello Steven,
I think that you could get a pretty decent low cost ADC, it is just to decide on what type of digital output you need/want and what type of serial input is/are available.
A least expensive, simple solution would be to have USB and I2S or SPDIF outputs.
That could be handled by a single chip plus associated components. Like PCM2902C can be pretty much as standalone (no requirement for software) sending USB or SPDIF datastream direct to digital input device.
Or you could divide the task of conversion and transmitting, which could give more flexible output options. For example the TI/Burr Brown PCM4201 could be used as the ADC, and then the PCM format data sent to a digital transmitter (DIT4096 as shown in the data sheet). From there go optical or twisted pair/coax. You can transmit to AES standard to a compatible receiver.
Have a look at the application notes for the PCM4201 as they give a good idea what could be done.
I do like your idea of the digital guitar, and I think that it would be no problem to build in this feature.
Hello Steven,
I think that you could get a pretty decent low cost ADC, it is just to decide on what type of digital output you need/want and what type of serial input is/are available.
A least expensive, simple solution would be to have USB and I2S or SPDIF outputs.
That could be handled by a single chip plus associated components. Like PCM2902C can be pretty much as standalone (no requirement for software) sending USB or SPDIF datastream direct to digital input device.
Or you could divide the task of conversion and transmitting, which could give more flexible output options. For example the TI/Burr Brown PCM4201 could be used as the ADC, and then the PCM format data sent to a digital transmitter (DIT4096 as shown in the data sheet). From there go optical or twisted pair/coax. You can transmit to AES standard to a compatible receiver.
Have a look at the application notes for the PCM4201 as they give a good idea what could be done.
I do like your idea of the digital guitar, and I think that it would be no problem to build in this feature.
Hi Steven,
I was wondering if you had a chance to look at those data sheets, and if you think that is where you want to go with it. The thing is other than USB, there is not much development being done as far as an open source digital standard for guitars. In the digital world you really need a simple plug and play solution, and DIYers are not too keen on ''propietary'' stuff from manufacturers that won't be compatible. SPDIF and AES seem to be cool in the digital audio world.
What do you think?
I was wondering if you had a chance to look at those data sheets, and if you think that is where you want to go with it. The thing is other than USB, there is not much development being done as far as an open source digital standard for guitars. In the digital world you really need a simple plug and play solution, and DIYers are not too keen on ''propietary'' stuff from manufacturers that won't be compatible. SPDIF and AES seem to be cool in the digital audio world.
What do you think?
Hi Shanx,
I have had a quick look at PCM2902C. Looks good. 16 bit 48KHz, ~90DB, THD of 0.01%. 5V part, so the reference voltage may need to be less than 5V, but the rest looks great.
I may wire some simple schematic with the pre amplifier I have posted or another one with current to voltage converter which I have an ide of, but, I am afraid, I may not be able to purchase this IC nor the good quality reference voltage IC from the general purpose shops. Instead, I may need to go to Electrosonic but they have minimum requirements and need VISA information and do not take PayPal and need the shipping to be paid too. Long ago, they had a walk in shop on Victoria Park and Gordon Baker but they closed this.
I have had a quick look at PCM2902C. Looks good. 16 bit 48KHz, ~90DB, THD of 0.01%. 5V part, so the reference voltage may need to be less than 5V, but the rest looks great.
I may wire some simple schematic with the pre amplifier I have posted or another one with current to voltage converter which I have an ide of, but, I am afraid, I may not be able to purchase this IC nor the good quality reference voltage IC from the general purpose shops. Instead, I may need to go to Electrosonic but they have minimum requirements and need VISA information and do not take PayPal and need the shipping to be paid too. Long ago, they had a walk in shop on Victoria Park and Gordon Baker but they closed this.
Hi Steven, I think the PCM2902C could be a good start too.
I have a couple of local suppliers I deal with , who may be able to get a few if you want and we could work things out with paypal. When the next component buy comes around I will let you know. I would be interested in this from a ''DIY kit'' perspective, so maybe some other DIYers here would be interested also with a little development. Let me know what you think as it is up to you.
I have a couple of local suppliers I deal with , who may be able to get a few if you want and we could work things out with paypal. When the next component buy comes around I will let you know. I would be interested in this from a ''DIY kit'' perspective, so maybe some other DIYers here would be interested also with a little development. Let me know what you think as it is up to you.
Just a little comment, I know there was a lot of back and forth from all of us about tube vs. solid state analog vs. digital. I am still relatively neutral on this. I have performed live and recorded with both. Yes a tube amp sounds great live, but tricky to get consistent results with them..mics, room dynamics, the darn crossfeed from the drummer belting it out. To me the digital option is also very practical tool, having recorded with a fully digital rig and used totally software based simulation. I have also played live with a fully analog pedalboard (gasp) plugged into a Line 6 POD (Digital gasp!) and just used the pod for the digital mic'd amp model, from there right into an analog PA mixer board, very practical and very convincing sound. To me there is no right or wrong way to do it, as they are all useful tools to make music. I hope I stayed neutral saying that ;-)
Here's the fully digital loudpeaker:
Digital loudspeaker - Patent # 7215788 - PatentGenius
Based on an arrays of 'binary' piezo transducers.
Digital loudspeaker - Patent # 7215788 - PatentGenius
Based on an arrays of 'binary' piezo transducers.
I cannot comment on this. I am interested in tubes because I've never seen one (other than inside the TV, radio, etcetera, and in the flea market). I have only heard stories.
I have only plugged a base and a hollow guitar with a separately added pick up hum into a tube radio. Sounded good. Seen a friend to use a tube Marshall with a base guitar.
The only records I have made are with a microphone plugged into a PC and a guitar either plugged the same way to the "Line In" or to a 10W amplifier ~ 1 yard away from the microphone, thus the microphone takes the guitar and the voice.
Well, I have also performed life. On the beach for coins. No microphone, no amplifier. The trick is to slam on the guitar chords as loud as possible to be heard as far as possible and to sing with a full voice. Thus people would have more while to listen and may drop a coin or two. When I take "breaks" and sing at lower volume, people do not drop almost anything! I have just given a professional secret to a lot of competitors!
I've recently watched Blackstone with Chantal Krevizuk who acted as being kidnaped and sang on a field. In case Chantal sings this way (low volume) on the beach, Chantal would get money only because Chantal is Chantal. Otherwise wouldn't make even for a burger!
I have only plugged a base and a hollow guitar with a separately added pick up hum into a tube radio. Sounded good. Seen a friend to use a tube Marshall with a base guitar.
The only records I have made are with a microphone plugged into a PC and a guitar either plugged the same way to the "Line In" or to a 10W amplifier ~ 1 yard away from the microphone, thus the microphone takes the guitar and the voice.
Well, I have also performed life
. On the beach for coins. No microphone, no amplifier. The trick is to slam on the guitar chords as loud as possible to be heard as far as possible and to sing with a full voice. Thus people would have more while to listen and may drop a coin or two. When I take "breaks" and sing at lower volume, people do not drop almost anything! I have just given a professional secret to a lot of competitors! I've recently watched Blackstone with Chantal Krevizuk who acted as being kidnaped and sang on a field. In case Chantal sings this way (low volume) on the beach, Chantal would get money only because Chantal is Chantal. Otherwise wouldn't make even for a burger!
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