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#41
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Kevin Aylward wrote:
There is a story to this. I discovered this trick at the age of 16. It was very apparent that my guitar amp/speaker was "midderly", which the tone controls could not correct for. I discovered that using a transformer as an inductor and a parallel capacitor in series with the signal worked wonders. Yes I have been fiddling with electronics sine the age of 11, especially with regard to sound. I then became acquainted, at this same age, of the bridge T. This is 2 series resisters, with a cap to ground. The 2 series resisters are bypassed with another cap. This gives two paths, one for high frequency, and one for low. Now for the really interesting bit. I actually remember the values, yet I have never confirmed the response in spice, well until right now, today as I am typing. The values were 47k, 47nf, and 1nf. The response is a 28db notch at, low and behold, 500Hz! Congratulations! You (along with hordes of 14 year old thrash metal bedroom guitarists worldwide) discovered the "scooped" guitar sound. It may sound sweet on its own, but after a while, most people realize that it's practically useless in any real world situation. Kinda like ..007-.028 guitar strings. I have spent a *lot* of time playing with tone controls, and their design. I bet nobody else around here has done that. BTW, while I do realize that you probably use the term "tone control" simply to **** people off, I really don't understand why you keep talking about "resisters"? /martin. |
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#42
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Martin Andér wrote:
Kevin Aylward wrote: There is a story to this. I discovered this trick at the age of 16. It was very apparent that my guitar amp/speaker was "midderly", which the tone controls could not correct for. I discovered that using a transformer as an inductor and a parallel capacitor in series with the signal worked wonders. Yes I have been fiddling with electronics sine the age of 11, especially with regard to sound. I then became acquainted, at this same age, of the bridge T. This is 2 series resisters, with a cap to ground. The 2 series resisters are bypassed with another cap. This gives two paths, one for high frequency, and one for low. Now for the really interesting bit. I actually remember the values, yet I have never confirmed the response in spice, well until right now, today as I am typing. The values were 47k, 47nf, and 1nf. The response is a 28db notch at, low and behold, 500Hz! Congratulations! You (along with hordes of 14 year old thrash metal bedroom guitarists worldwide) discovered the "scooped" guitar sound. It may sound sweet on its own, but after a while, most people realize that it's practically useless in any real world situation. Kinda like .007-.028 guitar strings. You are certainly entitled to your opinion. I have spent a *lot* of time playing with tone controls, and their design. I bet nobody else around here has done that. That's correct, not many have. Hands up all those analogues designers in here? Hands up those that have opened up mixers and soldered on capacitors for tone experiments? BTW, while I do realize that you probably use the term "tone control" simply to **** people off, I have already explained why. They are controls that effect, now get this, the tone of the sound. Dah.... Some of us, are actually not really into all that pretensions "sonic transparency" bull****. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#43
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Kevin Aylward wrote:
You are certainly entitled to your opinion. No ****? I have spent a *lot* of time playing with tone controls, and their design. I bet nobody else around here has done that. That's correct, not many have. Hands up all those analogues designers in here? Hands up those that have opened up mixers and soldered on capacitors for tone experiments? What does being an analog designer have to do with experimenting with equalizers? I'd bet most people who ever opened up a piece of gear to modify it aren't analogue designers. You certainly don't have to be an analog designer to hear the differences between different capacitor values. Hell, most of the time, you don't even have to be an analog designer to understand why it sounds different. Also, switching capacitors and poking around inside gear isn't even necessary to "play around with tone controls". Just taking a parametric equalizer, playing around with the controls and learning what they do to different sounds is IMO the best way to learn how to use equalizers. Ever noticed how people that know absolutley nothing about electronics sometimes mix music with great success? I have already explained why. They are controls that effect, now get this, the tone of the sound. Dah.... Well, the steering wheel of your car controls the direction you're going. Not a lot of mechanics call it a "direction control". /martin. |
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#44
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On Thu, 19 May 2005 17:03:37 -0700, playon wrote:
The Kevin Aylward $150 special. .... which only even actually exists on paper. |
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#45
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Agent 86 wrote:
On Thu, 19 May 2005 17:03:37 -0700, playon wrote: The Kevin Aylward $150 special. ... which only even actually exists on paper. It doesn't NEED to be built. We KNOW it will sound absolutely spectacular. /martin. |
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#46
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Martin Andér wrote:
Agent 86 wrote: On Thu, 19 May 2005 17:03:37 -0700, playon wrote: The Kevin Aylward $150 special. ... which only even actually exists on paper. It doesn't NEED to be built. We KNOW it will sound absolutely spectacular. If it were built, it wouldn't have any "sound" at all. It would be a straight piece of wire with gain. With all due respect, you don't have the technical background to understand this. The background you do have is apparently based on a background equivalent to esp, and astrology. There is no magic in designing audio equipment. It is no different from any other electronic discipline. Its simply amps and volts over time. Its that simple. The information most layman have on audio electronics is misinformation. I don't have time to debate this further. Arny's thread on the experimental evidence of the inability of people to detect certain differences covers the essentials on this matter. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#47
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Martin Andér wrote:
Kevin Aylward wrote: You are certainly entitled to your opinion. No ****? I have spent a *lot* of time playing with tone controls, and their design. I bet nobody else around here has done that. That's correct, not many have. Hands up all those analogues designers in here? Hands up those that have opened up mixers and soldered on capacitors for tone experiments? What does being an analog designer have to do with experimenting with equalizers? I'd bet most people who ever opened up a piece of gear to modify it aren't analogue designers. You certainly don't have to be an analog designer to hear the differences between different capacitor values. Hell, most of the time, you don't even have to be an analog designer to understand why it sounds different. The were two questions. Apparently, you missed the second. Also, switching capacitors and poking around inside gear isn't even necessary to "play around with tone controls". To do it completely, you may well have to. Just taking a parametric equalizer, playing around with the controls and learning what they do to different sounds is IMO the best way to learn how to use equalizers. This doesn't work for shelving treble and bass controls. Boosting the bass at 100Hz is nothing like boosting a bass control that has a design shelf frequency at 100Hz, or any other frequency. Only if the mixer has sweepable shelving frequencies can you play with them. Even then, if is a simple design, the response curves are not the same. Ever noticed how people that know absolutley nothing about electronics sometimes mix music with great success? That is entirely irrelevant to the point being made. I have already explained why. They are controls that effect, now get this, the tone of the sound. Dah.... Well, the steering wheel of your car controls the direction you're going. Not a lot of mechanics call it a "direction control". Pointless analogy. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#48
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#49
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#50
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Kevin Aylward wrote: wrote: Kevin Aylward wrote: wrote: Kevin Aylward wrote: anahata wrote: Kevin Aylward wrote: Have you tried adjusting the tone controls, like taking some mid out at 600 Hz? Or backing of the front end gain a little and compensating further up the chain? That's all very well, but one of the nice things about good mic pres (so I read here, I can't afford one myself) if that you *don't* have to EQ them to hell and back to make them sound right. There are indeed quite a few that do claim that expensive mic preamps are required for a good sound. I, as do many others, disagree. Those like me take the view that expensive mic preamps are a scam, indeed a complete rip-off. We see it as placebo effect where people imagine all sorts of wonderful things after the fact in order to feel comfortable about spending such a large amount of money, after being suckered by snake oil salesman. Others have different views. From a technical point of view, the specs of these expensive mic amps, for example distortion and frequency response, and the specs of a cheap mixer mic amp, are by and large completely equivalent, and have specifications figures that many in the industry consider a "straight piece of wire with gain". Quite apart from the fact that preamps appear to sound different, That is an opinion that many have. I and others disagree. there are definitely functional differences between them. Sometimes. The cheap mixer mic amp doesn't even have enough clean gain to use with certain microphones on certain sources, but the better preamps do. One might need a mixer with a pad. One might not. Depends on the mixer design. My point is that if you plug a ribbon mic into a cheap mixer and try to record a flute, you won't have enough clean gain to do it. Ok. I misread that. You just mean gain. The clean bit implied to me that the signal was too large. I meant clean gain. You can get a lot of gain if you crank a Behringer all the way, it just starts to sound really, really bad. Not in a "might be able to tell the difference under controlled conditions" type way, in a very obvious noisy way. Apart from the fact the preamps do sound different, good preamps have a wider window of effective operation than inexpensive preamps. This means that they work in a wider variety of conditions, with a wider variety of mics and have a wider band of effective gain. I have a little old Neve discrete console and a Behringer console. I think that the Neve sounds better, but quite apart from this, one requires much less messing about to get a good sound from the Neve. One can put the mics that one wants to use where one wants to put them, instead of having to worry about it. Gain staging just isn't as much of an issue. When one is talking about tools, one doesn't judge them only by the results that they produce, one judges them by how easy they make it to get the results. One wouldn't necessarily judge a hammer by looking at a nail it had knocked in. A mic preamp is a very different animal from an audiophile amplifier - it must be used in lots of different ways in lots of different settings. It's not like a hifi amp that you operate simply with an on/off switch and a volume control. I wholehearted agree with the idea of DBT tests for hifi amplifiers, but I think that they tell only a small part of the picture for preamps. I wouldn't be surprised if it is hard to tell the difference between a Mackie and a Millenia if one was using a cheap, hot Chinese condensor mic, but I think that it would be easy with an RCA 44. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#51
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Mike Rivers wrote:
In article writes: What relevance has this to with the fact that extensive controlled listening tests have shown that for equipment of certain specs, there is no audible difference? Check out the Arny thread. How extensive? How controlled? What specs? You keep pointing out what seem to be trivial articles. What I am doing is just poping up some examples when they become available. Did you listen the mp3 at http://www.stereophile.com/news/050905debate/ ? The point here is that we have a confirmed golden ear individual, who tells us that he has participated in many proper trials, yet failed to detect the differences that he claimed he heard outwith trials. He then just dismisses the trials for essentially, because he doesn't believe the results. This is truly a dead issue. Many, many years, ago amps were not so good. This is not true since the last 20 years at least. Sure, you can go around and say you want all the references, they do exist, but I just haven't got the time to locate them. I'm sure Arney can get you the details. There is simply no magic here. This whole debate is just bloody daft. The issue is really a psychological one, not a technical one. people believe what they want to believe, despite the facts. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#52
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On Thu, 19 May 2005 10:50:55 -0400, Scott Dorsey wrote
(in article ): In article . com, EADGBE wrote: I am going to be upgrading my home studio's mic preamps. I have been using the preamps in my MOTU interface and in my SoundCraft Spirit mixer, but I have always found them lacking a bit in detail and a bit "harsh" sounding with certain mics, especially my AKG C414TLII. Part of this is because the C414 TLII is just a harsh mike. My budget is around $3,000.00. I would be interested in hearing TWO things: 1) What do you consider to be a good "all around" mic pre. 2) Some specifics on why you recommend that mic pre. Get a preamp intended to be as neutral as possible. Ones I would recommend include the original Great River, the Millennia Media HV-3, and the John Hardy gadgets. All of these are well in your price range, and all of them pretty much pass a straightwire test. They are all worth auditioning. --scott The three most important things to consider with mics and preamps is; Matching, matching and matching. The C414 sounds fine with the right preamp. My GML, Amek NEVE 9098, Millennia Media STT-1, John Hardy and Jensen are good matches. Ty Ford -- Ty Ford's equipment reviews, audio samples, rates and other audiocentric stuff are at www.tyford.com |
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#53
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20 hz, 20k hz, what the F**K!
First, how do you determine the numeration of these shelf EQ frequencies? 3db down from max boost/cut?, 3 db up/down from the turnover point? The max frequency of boost/cut? Here's the problem: Bell curves are easy to determine, the 'ol -3 db slope. How do you determine the shelf EQ frequency? There is NO Standard. It's what you want to call it. Only a plot will tell you where the shelf EQ is working, Hence, the decades long confusion to the operators as to what they hear vs the numbers written on the console EQ. Show the plot, end the confusion. Jim Williams Audio Upgrades |
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#54
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Hmmm.... So let me get this straight. As in wire with gain;
A Mackie pre with a couple of 2sc2545 hitachi transistors around a nasty upc4560 opamp is going to measure and sound like the high end stuff. FFT analysis shows different. So do the ears. But that's not important. It's all in the AP tests! Can they do .0002% CCIF IMD? Can they do clean gain up to the phase shift turnover point at 200k hz? Can they offer -135 db ein? Can they slew over 20 v/us, or even 200 v/us? We need evidence so I can stop making this expensive stuff. I need a Radio Shack schematic that will meet/beat my own design. I want to save money. I want the same sonics. I want it to cost less than an RNP. I want transistors that do 1.5 ghz GBW, .3 nv / hz /2 noise, 200 ma output current and a 100 v operation. I want coupling caps that don't cost $12 each that have micro ohms esr at 100k hz. Please show me how. Inquiring minds want to know. Please don't tell me to lose my hearing first! Jim Williams Audio Upgrades |
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#55
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Mike Rivers wrote:
The loading on the mic might well make a difference, in principle. The inductance of a transformer as a load might well makes a difference, in principle. If I can be provided with the spec of RLC of mics and RLCs of the transformers, I can determine whether such effects are audible by simply running a few simulations. Now you're beginning to see a glimmer of light. The problem is that you can't be provided with the general RLC model for a microphone, so you can't optimize for it. Royer (and now Blue, and perhaps others) are approaching that problem by building a "preamp" (not much gain, with output still nominally at mic level) into the microphone case, and matching its input characteristics to the microphone "motor." In the case of the Royer, it's a unity gain buffer amp. The voltage gain comes from the transformer that precedes it. |
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#56
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Kevin Aylward wrote:
Martin Andér wrote: Agent 86 wrote: On Thu, 19 May 2005 17:03:37 -0700, playon wrote: The Kevin Aylward $150 special. ... which only even actually exists on paper. It doesn't NEED to be built. We KNOW it will sound absolutely spectacular. If it were built, it wouldn't have any "sound" at all. It would be a straight piece of wire with gain. With all due respect, you don't have the technical background to understand this. With all due respect, you are talking out of your ass. |
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#57
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Kevin Aylward wrote:
What does being an analog designer have to do with experimenting with equalizers? I'd bet most people who ever opened up a piece of gear to modify it aren't analogue designers. You certainly don't have to be an analog designer to hear the differences between different capacitor values. Hell, most of the time, you don't even have to be an analog designer to understand why it sounds different. The were two questions. Apparently, you missed the second. Apparently, you did not understand the point I was making. Why did you not just ask the second question? Being an analog designer means close to nothing as you are listening for changes in sound when modifying capacitor values in an equalizer. It's not like you're designing the equalizer! But I have noticed that you seem to enjoy pointing out that you're an analog designer. Are you expecting me to be impressed? Intimidated even? Also, switching capacitors and poking around inside gear isn't even necessary to "play around with tone controls". To do it completely, you may well have to. Well, perhaps. Doesn't make a whole lot of differnece though, since I am pretty sure a lot of the people reading this group have done it. Just taking a parametric equalizer, playing around with the controls and learning what they do to different sounds is IMO the best way to learn how to use equalizers. This doesn't work for shelving treble and bass controls. Boosting the bass at 100Hz is nothing like boosting a bass control that has a design shelf frequency at 100Hz, or any other frequency. Only if the mixer has sweepable shelving frequencies can you play with them. Even then, if is a simple design, the response curves are not the same. OK, so get a bunch of different equalizers then. The point I am trying to make is that the best way to learn how to use an equalizer is to use one. You were originally implying that the people here don't know how to use "tone controls" -- I say they do. I think they also know how not to use them. I have already explained why. They are controls that effect, now get this, the tone of the sound. Dah.... Well, the steering wheel of your car controls the direction you're going. Not a lot of mechanics call it a "direction control". Pointless analogy. Not at all. /martin. |
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#58
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In article . com,
wrote: I want transistors that do 1.5 ghz GBW, .3 nv / hz /2 noise, 200 ma output current and a 100 v operation. I want coupling caps that don't cost $12 each that have micro ohms esr at 100k hz. I would settle for ANY transistors with reasonably well-controlled hFE, 500 KHz GBW, and 100V operation this morning. And coupling caps that don't explode and spray green stuff on the board. Is that too much to ask for? --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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#59
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In article ,
Kurt Albershardt wrote: Mike Rivers wrote: The loading on the mic might well make a difference, in principle. The inductance of a transformer as a load might well makes a difference, in principle. If I can be provided with the spec of RLC of mics and RLCs of the transformers, I can determine whether such effects are audible by simply running a few simulations. Now you're beginning to see a glimmer of light. The problem is that you can't be provided with the general RLC model for a microphone, so you can't optimize for it. Royer (and now Blue, and perhaps others) are approaching that problem by building a "preamp" (not much gain, with output still nominally at mic level) into the microphone case, and matching its input characteristics to the microphone "motor." In the case of the Royer, it's a unity gain buffer amp. The voltage gain comes from the transformer that precedes it. Which brings to mind that ANYONE that can build an active buffer amplifier for a ribbon microphone that actually works and allows you to eliminate the transformer will have it made. Folks have been trying to do that for fifty years now without success. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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#60
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I haven't listened to to high end mic preamps, other then through
final CDs. Given the opportunity a) Would you be willing to compare them in an honest blind test b) Would/could you be able to do it without bias/expectation that they'll all sound the same? I suppose a couple controls with obvious deficiencies would have to be put in to mitigate b) a bit |
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#61
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"Mike Rivers" wrote in message news:znr1116587430k@trad... In article writes: What relevance has this to with the fact that extensive controlled listening tests have shown that for equipment of certain specs, there is no audible difference? Check out the Arny thread. How extensive? At least as extensive as the equipment shown in these two lists: http://www.pcabx.com/product/amplifiers/index.htm http://www.pcabx.com/product/soundcard/index.htm How controlled? http://www.pcabx.com/ What specs? typically: http://www.pcavtech.com/soundcards/C...luxe/index.htm http://www.pcavtech.com/pwramp/macrot-5000VZ/index.htm |
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#62
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Kurt Albershardt wrote:
Kevin Aylward wrote: Martin Andér wrote: Agent 86 wrote: On Thu, 19 May 2005 17:03:37 -0700, playon wrote: The Kevin Aylward $150 special. ... which only even actually exists on paper. It doesn't NEED to be built. We KNOW it will sound absolutely spectacular. If it were built, it wouldn't have any "sound" at all. It would be a straight piece of wire with gain. With all due respect, you don't have the technical background to understand this. With all due respect, you are talking out of your ass. "We KNOW it will sound absolutely spectacular" was a statement clearly meant to mean the opposite of your belief, and so indicates to me that you are unaware of standard knowledge in analogue design accepted by 10,000s of engineers. It implies a lack of belief that a simulated design will not work in practice. This is not so, 1000s of i.c designs are routinely done by simulation that work first time as intended. It costs way too much to fab a chip, e.g. $100k for a mask set, to have to rely on bench work. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#64
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Agent 86 wrote:
playon wrote: The Kevin Aylward $150 special. ... which only even actually exists on paper. That's some fancy paper. A hunnerd fifty for paper. Looks good on the screen. -- ha |
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#65
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wrote:
Hmmm.... So let me get this straight. As in wire with gain; A Mackie pre with a couple of 2sc2545 hitachi transistors around a nasty upc4560 opamp is going to measure and sound like the high end stuff. Probably, if operated within its limits. Although I wouldn't use one of those as a reference. Just about any other decent semi-pro mixer and its a definite. FFT analysis shows different. So do the ears. But that's not important. It's all in the AP tests! I don't know what AP tests mean. If you mean A/B tests, they invariable show no difference in well spec equipment. Can they do .0002% CCIF IMD? Can they do clean gain up to the phase shift turnover point at 200k hz? Can they offer -135 db ein? Can they slew over 20 v/us, or even 200 v/us? Why would they want to do that? 20V at 20Khz is only 2.5v/us 0.01% imd is quite sufficient, 0.05% is fine according to standard A/B tests. Static phase shift in this context is simply undetectable, therefore irrelevant. -135db ein is theoretically impossible from a 150 ohm nominal source. Its -133db max. Well, not unless we all sitting here freezing our balls off. We need evidence so I can stop making this expensive stuff. You can, the evidence is all over the place. The final consumer just don't notice. I need a Radio Shack schematic that will meet/beat my own design. I want to save money. I want the same sonics. I want it to cost less than an RNP. I want transistors that do 1.5 ghz GBW, .3 nv / hz /2 noise, 200 ma output current and a 100 v operation. I want coupling caps that don't cost $12 each that have micro ohms esr at 100k hz. None of that is required. Please show me how. Show me why the above is required. Inquiring minds want to know. Those of us that have actually inquired, have determined the inquiry was pointless. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#66
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wrote:
I haven't listened to to high end mic preamps, other then through final CDs. Given the opportunity a) Would you be willing to compare them in an honest blind test Of course. b) Would/could you be able to do it without bias/expectation that they'll all sound the same? Don't think about pink elephants. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#67
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Scott Dorsey wrote:
In article , Kurt Albershardt wrote: Mike Rivers wrote: The loading on the mic might well make a difference, in principle. The inductance of a transformer as a load might well makes a difference, in principle. If I can be provided with the spec of RLC of mics and RLCs of the transformers, I can determine whether such effects are audible by simply running a few simulations. Now you're beginning to see a glimmer of light. The problem is that you can't be provided with the general RLC model for a microphone, so you can't optimize for it. Royer (and now Blue, and perhaps others) are approaching that problem by building a "preamp" (not much gain, with output still nominally at mic level) into the microphone case, and matching its input characteristics to the microphone "motor." In the case of the Royer, it's a unity gain buffer amp. The voltage gain comes from the transformer that precedes it. Which brings to mind that ANYONE that can build an active buffer amplifier for a ribbon microphone that actually works and allows you to eliminate the transformer will have it made. Folks have been trying to do that for fifty years now without success. The problem here is that the ribbon resistance is say 1 ohm. This means preamps contribute significantly to the noise. Transformers are useful as noiseless amplifiers. One could use a 2n3055, 15A power transister as its rbb' is 2ohms. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#68
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Mike Rivers wrote:
In article writes: The loading on the mic might well make a difference, in principle. The inductance of a transformer as a load might well makes a difference, in principle. If I can be provided with the spec of RLC of mics and RLCs of the transformers, I can determine whether such effects are audible by simply running a few simulations. Now you're beginning to see a glimmer of light. There is nothing new here about considering the source impedance. The question about is about those "huge" differences that people are claiming, possibly due to them. The problem is that you can't be provided with the general RLC model for a microphone, so you can't optimize for it. All I am after is a first order model to do some sums. It is well known that for guitars, that loading makes a large difference. Typical inductances might be say, 2H. A 100k load is 7.9Khz for the 3db point. Compared to a 1Mohm, its easily detectable. Even a TV co-ax verses a normal cable is easily distinguished when used as a guitar cable. Royer (and now Blue, and perhaps others) are approaching that problem by building a "preamp" (not much gain, with output still nominally at mic level) into the microphone case, and matching its input characteristics to the microphone "motor." It's kind of like what good designers of powered loudspeaker systems do - include the most unpredictable interface (the mic-input stage or output stage-loudspeaker) in the system design, turning this ambiguous interface into something known and presumably intelligently designed around. I haven't listened to to high end mic preamps, other then through final CDs. More important, you haven't listened to the original source. If all you hear is the final product, you have no clue as to the performance of what equipment created it. Which brings one to the final point. The final point in the listening chain. The consumer. Make a normal music CD with the only thing different, is that one has the mics through the Mackie CFX, the other through the high end one, I bet you 10 pints of Guinness, no one can tell the difference, in an AB listening test. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#69
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wrote:
Kevin Aylward wrote: wrote: I wholehearted agree with the idea of DBT tests for hifi amplifiers, but I think that they tell only a small part of the picture for preamps. I don't, so we will leave it there. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#70
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Kevin Aylward wrote: wrote: Kevin Aylward wrote: wrote: I wholehearted agree with the idea of DBT tests for hifi amplifiers, but I think that they tell only a small part of the picture for preamps. I don't, so we will leave it there. No I won't. I've just explained to you why "sounding good" is only one of many requirements we have for a mic preamp. You can't judge anything other than sounding good with a DBT. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#71
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Kevin Aylward wrote:
If it were built, it wouldn't have any "sound" at all. It would be a straight piece of wire with gain. Put up or shut up. You are all mouth and no preamp, so far, and talking out your ass is putting it politely. I think the forest hereabouts might have better ears than you do, and any local tree is as good a mic preamp as the one you've shown us so far, timber pulp being a precursor to paper. -- ha |
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#72
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hank alrich wrote:
Agent 86 wrote: playon wrote: The Kevin Aylward $150 special. ... which only even actually exists on paper. That's some fancy paper. A hunnerd fifty for paper. Looks good on the screen. You need to get to grips just how its actually done in i.c. design, i.e. transistor level design in 100's of companies, by 10,000s of engineers. Having simulated designs work correctly, first time, is expected and usual. Like, you think a company can afford to throw away $100k mask sets and two months of fab time? Like, they spend $30k per year for each CAD tool seat for their 1000 engineers just to do bench work because you think simulation don't work? Simulation today, is amazingly accurate. Bench results and simulations typically agree, very, very well. The discrepancies are usually just because someone didn't do a particular simulation, not that than simulation wouldnt predict the correct results. Typical designers will run say, 10,000 runs of various distributions to ensure the design will work, but sometimes you miss a few. Your talking from ignorance mate. Simulation is the way, probably, 99% of all analogue design is done today, that is, essentially all analogue design is done by i.c companies. Kevin Aylward http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#73
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Wow Hank,
I may have been thinking it, but that was a pretty vitriolic post. If someone ****es me off that much I just plonk them. Anyway I have nice pres and what I noticed most when I started buying and using them to replace my Mackie board was the details of the room and mic that weren't apparent previously. This caused me to have to upgrade the room and mike collection till all things were more on par. The next step is to upgrade the converters, will it ever end? On Thu, 19 May 2005 23:16:09 GMT, (hank alrich) wrote: Kevin Aylward wrote: There are indeed quite a few that do claim that expensive mic preamps are required for a good sound. I, as do many others, disagree. Those like me take the view that expensive mic preamps are a scam, indeed a complete rip-off. I think the real ripoff is when near-deaf mother****ers like you come in here claiming to know something about sound. The stuff you've put up for listening sounds like upwiped ass connected to a kazoo through a high pass filter. Get your hearing checked. It's nearly gone. And put up the ****ing ten cent preamp champion you claimed to be able to foist on the world, the one that was going to show what a ripoff my Great River and Millennia pres are. A recipe for chicken**** soup is not a meal. When someone can connect a microphone to your chicken**** champion, then we'll see your mic preanmp design chops. So far your bird can't seem to get out of the coop. |
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#74
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On Thu, 19 May 2005 21:35:25 +0000, Kevin Aylward wrote:
The point is that there are many, affordable complete, quality mixers, costing less than a typical high end mic preamp, which are indistinguishable from each other sound wise. This seems an odd thing to say. If you compare a mackie or behringer and a decent high end pre like a good focusrite or Amek, they sound different. It takes a while to 'get it', but once you know what to listen for, it's not too hard to tell them apart. If comparing the same mic with the same voice/instrument in each pre, I can do it quite reliably, and have a friend with better ears who can tell every time. If comparing different mics on different instruments I think I would struggle to tell which pre was which. It's very hard to judge as I cannot recreate recording a whole band with different sets of pre's, but I find that using pres I like cuts down on the 'greyness' that tracking everything though a low end desk can give. It may be an illusion caused by different load impedances, transformer vs solid state front end or whatever, that is largely irrelevant: it's not really my concern as to how some mic pres sound good, but it is very much my concern to get a decent sound. I'd suggest giving it a go yourself, like so many things to do with recording tech you have to learn to ignore the specs and have a listen. You may find no audible difference at all between a $40 behringer and an Millennia, which in a way is the best result as you can save a load of money.  Kevin Aylward http://www.anasoft.co.uk/EE/index.html http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. |
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#75
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Kevin Aylward wrote:
Kludge writes: Which brings to mind that ANYONE that can build an active buffer amplifier for a ribbon microphone that actually works and allows you to eliminate the transformer will have it made. Folks have been trying to do that for fifty years now without success. The problem here is that the ribbon resistance is say 1 ohm. This means preamps contribute significantly to the noise. Transformers are useful as noiseless amplifiers. The ribbon resistance is often more than an order of magnitude lower than that! And in cases like that, the thermal noise of the transformer winding becomes a major, major issue. One could use a 2n3055, 15A power transister as its rbb' is 2ohms. Shure guys tried that in the seventies, and got a paper out of it but not much more. I forget what the main noise issue was in that case, but I have the paper here somewhere. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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#76
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On 20 May 2005 15:25:18 -0400, (Scott Dorsey) wrote:
Kevin Aylward wrote: The problem here is that the ribbon resistance is say 1 ohm. This means preamps contribute significantly to the noise. Transformers are useful as noiseless amplifiers. The ribbon resistance is often more than an order of magnitude lower than that! And in cases like that, the thermal noise of the transformer winding becomes a major, major issue. One could use a 2n3055, 15A power transister as its rbb' is 2ohms. Shure guys tried that in the seventies, and got a paper out of it but not much more. I forget what the main noise issue was in that case, but I have the paper here somewhere. Is the noise directly related to temperature? If so, a Peltier cell could substantially lower the temperature of a few transistors that aren't dissipating much heat. Or is this a useless idea? --scott ----- http://mindspring.com/~benbradley |
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#77
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Ben Bradley wrote:
On 20 May 2005 15:25:18 -0400, (Scott Dorsey) wrote: Kevin Aylward wrote: The problem here is that the ribbon resistance is say 1 ohm. This means preamps contribute significantly to the noise. Transformers are useful as noiseless amplifiers. The ribbon resistance is often more than an order of magnitude lower than that! And in cases like that, the thermal noise of the transformer winding becomes a major, major issue. One could use a 2n3055, 15A power transister as its rbb' is 2ohms. Shure guys tried that in the seventies, and got a paper out of it but not much more. I forget what the main noise issue was in that case, but I have the paper here somewhere. Is the noise directly related to temperature? If so, a Peltier cell could substantially lower the temperature of a few transistors that aren't dissipating much heat. Or is this a useless idea? Oh, man, I used to remember this stuff. Resistive noise (like the noise of the transformer) is called "thermal noise" because it's indeed directly related to temperature. But 1/f noise and shot noise aren't related to temperature. I don't know where the breakeven point is.... I know that with a high-Z source the 1/f noise is dominant and with a low-Z source the thermal noise becomes more significant but I don't remember the crossover points on the curve at all. --scott --scott ----- http://mindspring.com/~benbradley -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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#78
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#79
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#80
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wrote:
Anyway I have nice pres and what I noticed most when I started buying and using them to replace my Mackie board was the details of the room and mic that weren't apparent previously. Yep, the worth of the expenditure made for good preamps shows in the details captured. This caused me to have to upgrade the room and mike collection till all things were more on par. The next step is to upgrade the converters, will it ever end? Maybe not, but you can stop anytime... right?? g -- ha |
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