Yes - Abbey Road's biggest studio, which has been used for plenty of orchestral recordings doesn't sound much like a concert hall when standing in it. Its considerably less 'live'.
<edit> I do take issue with your reference to 'wild claims'. The inventor of ambisonics (Michael Gerzon) was the kind of guy who was the antithesis of that style. Very understated. Perhaps his followers have been prone to making wild claims, I don't know.
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Hi Demain,
You won't hear me disagree with you.
I haven't had any exposure to a Praxis system, so you're more of an expert there! I was careful when I bought the two sound cards I use. Both are capable of 24 bit record and playback, both sample at 96 Khz or 192 KHz. I'm just not sure what effect the OS on the computer might have. I have run the loop-back tests through a patch cord to be sure everything is accounted for.
The reason that I don't tend to use the sound-card systems as much is that my work area is undergoing a complete refit, and the real test instruments are better suited to the work. Once I have a proper interface made, I'll become more serious about characterizing the sound cards.
The fact of the matter is that the only real important thing is low short term jitter. Long term frequency drift or tolerance is not important at all - within reasonable limits.
Are we still talking about John's preamp, or approaches to designing linear circuits? We seem to be wayyy off course.
-Chris
You won't hear me disagree with you.
I haven't had any exposure to a Praxis system, so you're more of an expert there! I was careful when I bought the two sound cards I use. Both are capable of 24 bit record and playback, both sample at 96 Khz or 192 KHz. I'm just not sure what effect the OS on the computer might have. I have run the loop-back tests through a patch cord to be sure everything is accounted for.
The reason that I don't tend to use the sound-card systems as much is that my work area is undergoing a complete refit, and the real test instruments are better suited to the work. Once I have a proper interface made, I'll become more serious about characterizing the sound cards.
Completely agree, but to reasonable limits. I have seen GPS discipled oscillators sold for CD players and DACs. These are available in the popular frequencies seen in CD equipment. How's that for going out over the edge?
The fact of the matter is that the only real important thing is low short term jitter. Long term frequency drift or tolerance is not important at all - within reasonable limits.
Are we still talking about John's preamp, or approaches to designing linear circuits? We seem to be wayyy off course.
-Chris
How do they arrange the antenna? I can't get a GPS lock on my mobile phone when I'm indoors. I'm guessing these might be obsoleted by the latest Rubidium clock units which will definitely fit within an average-sized CD player, and a mere $1500 a piece in small quantities. As you point out, also very poor close-in phase noise...😱
<edit> I've just checked the datasheet of this beast and it doesn't actually say its rubidium. Just an atomic clock, 35g and 115mW.
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I have not seen a GPSDO for audio clocks. There are rubidium clocks both commercial (Esoteric) and china surplus FE 5680 programmable Rubidium oscillators. The FE 5680 has a good DDS and pretty good phase noise but not a match for a good crystal. The isochrone has provisions for connecting to a GPSDO. Probably only important if you are connecting to a TV network. A good GPSDO really takes 12-24 hours to dial itself in.
Consumers who don't understand new technology grasp for a way to understand it. If the real stuff is difficult to comprehend (phase noise and jitter) then you go for accuracy. Accuracy is pointless past a certain threshold, much looser than any decent crystal oscillator but if 5 ppm sounds real good. the .05 ppb must be much much better (but it may be much worse in the important part). If consumers don't understand the insides they will gravitate toward the jewelery on the outside (use more gold and silver).
Consumers who don't understand new technology grasp for a way to understand it. If the real stuff is difficult to comprehend (phase noise and jitter) then you go for accuracy. Accuracy is pointless past a certain threshold, much looser than any decent crystal oscillator but if 5 ppm sounds real good. the .05 ppb must be much much better (but it may be much worse in the important part). If consumers don't understand the insides they will gravitate toward the jewelery on the outside (use more gold and silver).
Hi abraxalito,
Well, I'm going for 10 MHz and distribution to my bench equipment. An external antenna is really the only way to go. The actual oscillator is an ovenized crystal. Short term stability should be great, unless it's using the older Motorola chip set.
This is insane overkill, and the only positive thing about it is the lower jitter that exists in a shock mounted, temperature controlled chamber. The GPSDO part is completely wasted as long term accuracy has no meaning for CD players.
Hi Demian,
-Chris
Well, I'm going for 10 MHz and distribution to my bench equipment. An external antenna is really the only way to go. The actual oscillator is an ovenized crystal. Short term stability should be great, unless it's using the older Motorola chip set.
This is insane overkill, and the only positive thing about it is the lower jitter that exists in a shock mounted, temperature controlled chamber. The GPSDO part is completely wasted as long term accuracy has no meaning for CD players.
Hi Demian,
That's my point. A good ovenized TCXO will provide the maximum benefit for a CD player. There is nothing else that the GPS angle brings to the table for this application. Nothing.
A week, and it must be continuously operated. That's to settle the drift out, but 24 hours should bring the jitter down enough.
Now, how can anyone who knows this industry argue with that? The larger the item is, and the more inconvenient it is, the better it must be. Never mind that the best things run smoking hot! No, the industry doesn't stand a chance. Truth was abandoned long ago.
-Chris
Yes, Takemitsu Memorial. ClassicsToday liked the following recording.
Günter Wand, LIVE IN JAPAN 2000
Fortunately, plenty of the room acoustics are recorded. Disney Hall comes across cooler, clearer, and with wonderful low frequency extension (the #2 quality : ). Such as Salonen's Helix for Orchestra.
More power to your ideas for a paradigm shift.
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Even with the close microphones, reverbation is quite apparent in the pauses when the instruments fall "silent".
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I have recordings which were made both on location and in the No 1 studio at the old Olympic Studios in Barnes, London. These include choral work, orchestral and small ensemble jazz and folk and some are on final mix 1/4" tape. On the best of these you can 'feel' the room around you.
I knew the old recording engineers and the reason they gave me for the great "hall effect" of some of these recordings was a C24 microphone suspended high above whatever was happening. Although close miking has become more or less the standard it does reduce to an absolute minimum the value of a studio/location with a great acoustic. But this is what the buyers of mainline recorded products are feed to believe is the closest to original listening experience. [There is still a C24 high aloft in the Albert Hall - which does not have a great acoustic]
I knew the old recording engineers and the reason they gave me for the great "hall effect" of some of these recordings was a C24 microphone suspended high above whatever was happening. Although close miking has become more or less the standard it does reduce to an absolute minimum the value of a studio/location with a great acoustic. But this is what the buyers of mainline recorded products are feed to believe is the closest to original listening experience. [There is still a C24 high aloft in the Albert Hall - which does not have a great acoustic]
Which is why I love my collection of Proms recordings from over the years! I also go every year to keep in touch with the "real" sound.
Angels and pinheads all of this, really ....
Angels and pinheads all of this, really ....
Normally I do not like to talk about credentials, resumes, or other aspects of someone's life history, mine in particular in places like this. I pointed that out when someone else did it recently. I view web sites of this type as places to exchange ideas and views that stand or fall on their own merit. However, it seems that who you are or what credentials you have sometimes influences how people view what you say in some places. This can be very misleading, even a fatal mistake in many instances (just look at what the "best" economists did to our economy.) I've met brilliant inventive people who were self taught, others with the most impressive credentials including PHDs and those who did post doctoral work who seemed clueless even about their own supposed area of expertise. I've met EEs with PE licenses who couldn't figure out how to wire a three way light switch. Would it really matter if you knew mine? It should already be clear from my postings that I've been well taught by many others.
While it is true that hearing live music is a unique experience for all of the senses and is never the same twice, we are dealing with only one of those senses here. The ability to duplicate the stimulus to that sense with very close similarity to the live experience is a matter of understanding the physics of the stimulus to be duplicated and the way our sensory and brain experience and evaluate that stimulus. This is where the basic research into finding successful means and understanding the limits of what can be done will be found. IMO there is a long way to go before those limits are reached. Throwing up your hands and saying it is impossible is not acceptable until there is a good reason why it is impossible. There are respected physicists who say it may someday be possible to travel faster than the speed of light, something which at least IMO seems absurd. And until relatively recently in the long history of human life on earth, many falacies were believed true not just by the common wisdom of the day but by the best minds of their times. That man would never fly. That traveling faster than 60 miles per hour would be fatal. That the earth is flat. The common wisdom didn't make it even slightly less round. I have good reason to believe that this area of effort has the potential to yield far better results than have been obtained so far. This like the automobile was to horse drawn carriage makers would be a threat to estabilished financial interests whose fate is tied to the current technology if it ever materialized. Small wonder there is a vested interest not only in rejecting challenges to it but in selling the notion that we have and are now pursuing the best of all possible worlds. I for one am not content to limit myself to 60 mph.
That's it! The acoustics of most playback rooms are all wrong. SY used to use a saying (from memory) that his wife doesn't want him to recreate an orchestra in the living room. It only makes sense to hear the sound of rooms designed for acoustic performance.
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NO WAY -
The title suggests mas--------y image creation rather than metaphysical thought.😀TRY
Bishop Barclay - Trinity College Dublin (me too!!!😉) - see wikipedia re Barclay and metaphysics.
My statement is based on the concept of spherical wavefronts. With two sources, it is not possible to synthesize a true spherical wavefront if the two drivers are 60 or so degrees apart. I purchased 128 4 inch full range drivers and 200 3/4 inch tweeters with the thought of creating a wall of drivers, each independently driven with programmable delay and intensity. It's a long term project.. Since it's just a hobby, it always takes back burner to life and a wicked honeydo list.
It also requires some really good dsp capability.
Excellent. If at any time you have questions or concerns that you feel I may be able to help with, PM me.
At home, the falloff rate may not follow square law. Large E-stat panels are closer to planar waves, line arrays fall as 1/r. Bose played more planar games.
There is also the polar stuff to contend with.. But you already know that stuff..
Agreed. I also have found no papers which discuss the spectral content vs angle of the instruments. If you sit close to the stage, brass will vary wildy if the performer is into the gig. Turning the horn varies each ear's spectral information slightly independently.
Oddly enough, that is also my personal preference. Second is a jazz combo in a small restauraunt, with the bassist two feet to my right...awesome.
Cheers, John
I think recordings can be segregated into two types by at least one point of view although the distinction isn't absolute. One type I call docmuented music where there is a genuine attempt to capture a musical event as it was heard or would be heard if performed live. Even where the electrical signals are manipulated by the recording engineer or balance engineer, it is in the service of that goal. This is usually the goal for recordings of music that some would consider fine art, classical music, jazz, opera. The other type I call manufactured music. This is music designed to please the listener although it has no real world analog. This is the category most popular music falls into. Various enhancement techniques including reverbs and now even pitch correction for singers who can't sing on key are used extensively. One isn't necessarily better than the other but for manufactured music, there is nothing that can be referred to by any rationale as an objective standard for comparison to evaluate how well that sound is reproduced. Both types of recordings have one thing in common, they are created to make as much money for the recording company as possible.
Crossover musicians perform both types and not always successfully. Usually the pop performer doesn't have the musical skills to perform serious music unless they were trained for it but chose a career as a pop performer instead. For example, Linda Ronstadt once tried to record the opera La Boheme because she loved it so much. Reportedly she fell flat on her face, didn't have even remotely anything like the voice to produce a product as marginally acceptable as a mediocre, let alone something of note (it's said of pitchers that their best friend is the batter's imagination.) It works the other way around too. The famous soprano Dame Kiri Tekanawa recorded many famous jazz songs on several albums. The reaction of jazz lovers....she swings like a rusty gate.
OTOH, there are musicians who can excell at both. Wynton Marsalis comes immediately to mind.
"At home, the falloff rate may not follow square law. Large E-stat panels are closer to planar waves, line arrays fall as 1/r. Bose played more planar games."
That is correct. I was thinking about the overwhelming majority of loudspeaker systems which for practical purposes can almost be considered point sources. For line arrays, surface arrays, and reflecting speakers the picture changes. That fact can be used to great advantage. I've always felt that the real attraction of panel type speakers didn't come from low distortion but from their large radiating surface. With the availability of resonably high quality drivers at low prices, building high quality array type speaker systems is now cheaper than ever. I may yet try a few. Remember the "sweet sixteen" that used 16 5" drivers in a 4 x 4 array that appeared in Popular Electronics in the 1960s?
I would like, after a long vacation, to talk about something near and dear to the original topic of this thread, that is: Power supply cleanliness.
First, I would like to say that power supplies today have very little hum or ripple, BUT they still don't sound 'clean', most of the time. If we go back into time, perhaps 50 years ago, the biggest problem seemed to be power supply ripple, that gave sort of a slight 'buzz' though the loudspeakers, when it was marginal. Today, it is something else. (more later)
First, I would like to say that power supplies today have very little hum or ripple, BUT they still don't sound 'clean', most of the time. If we go back into time, perhaps 50 years ago, the biggest problem seemed to be power supply ripple, that gave sort of a slight 'buzz' though the loudspeakers, when it was marginal. Today, it is something else. (more later)
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Uh oh...looks like a preamble to bybee rails....stay tuned for the next exciting chapter of....
Honestly, I like the concept. And, to top it off, the claims of noise reduction of up to 32,000 and almost zero rail impedance....very measureable indeed.
And worthy of discussion..
Have a pleasant vacation John..
Cheers, John
Ah...ps... Are they LDO's, or do the dirty rails have to be raised a vce or two?
Hi Soundminded,
-Chris
Completely agree. Besides, after school and post secondary education, we are all pretty much self taught. That is a reality of life.
No, I don't think you can divorce the senses from each other if your intent is to recreate a live experience. It doesn't even have to be music, and sounds will do fine. Especially those woodland sounds meant to relax a person. Smell-a-vision anyone?
No one has done that, but it is true at this state of the art.
-Chris
Hi John (N),
Loose the hounds!
-Chris
Yes, and here is a link to that inevitable discussion. May as well be prepared.
Loose the hounds!
-Chris
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