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Bipolar System Disorders / Re: I think my System is finally finished
« Last post by steve on Today at 05:23:38 PM »
"Here is a clue. One can obtain the same/similar specs by using a variety of parts types, and parts value. However, only one part type and value of each will give the most accurate music."

My head just exploded.

Don

Didn't mean to explode your head Don. I think I can simplify my comment further.

1. By varying the bias on a tube or ss device, the distortion pattern will vary. The distortoin spectrum might not
be that different, but enough if it involved 2nd vs 3rd, or better yet 2nd vs 9th order. The higher the harmonic, the lower the % to be perceived.

2. One sees so many specs that state 0,1db from 20 to 20khz or +/- 0,1db 20 to 20khz (0,2% total variation). Very rarely is the spec going to be exactly 0,1db at 20hz or 20khz. It could be -0,35db, -0,78db or -0,92db at either 20hz, or 20khz.

Remember that - 0,1db means the frequency response lowered only a small amount, about ~60db down from the midrange reference. However, when I adjust my control 1 in 100,000, we are talking nearly -100db change. Changing my 5 foot long speaker wire from 11 strands of 18 gauge wire to 10 strands is also an incredibly small change in resistance and inductance.

As such a -60db change is monsterous when we can perceive a -100db or lower change in tonal balance. An example of preamplifiers, one could be down -54db at 20khz and another down -78db at 20khz, and a third -92db down.

All it takes is a varying of the resistor resistance values, materials, and capacitor types and values. There are more, but let's limit our scope.

3. Capacitors are notorious for being inaccurate, as Dave mentioned. A capacitor is two foils separated by an insulator. Usually the foils/insulator are wrapped around and around, for example let's say 100 turns.

If one measures with a scope, meter, you won't see much of a difference between capacitors? Simply put, a scope or meter is not sensitive enough, nor do they measure all parameters.

The equation 1/2piFC equation (1/6.28 times frequency times capacitance in farads) doesn't really tell us a whole lot either. It is simply an equation that tells us the approximate capacitive reactance (AC resistance) at a particular frequency. It does not give us any information concerning the dielectric absorption, nor the equivalent serices problem.
     
     a. In simple terms, the dielectric absorption problem is electrons sticking to the insulation when they should let go and travel in the circuit. Below is a test demonstrating this effect in voltage (a form of signal). The old fashion picture tube test is another way. High DA causes a lack of dynamics and blurring as the electrons slowly release from the insulation.

     b. The termination of a capacitor's foils to lead wires affects the charging and discharging of a capacitor. A capacitor actually "fully" charges and discharges vs frequency (perfect capacitor). 20khz per second is mighty fast.

Some manufacturers simply terminate the leads at one tiny singular point on one foil edge of one foil turn, instead of contacting all the edge of all 100 turns of the foil. As a result the resistance and inductance varies between the foil at the termination and the foil far away from the termination. As a result, both the resistance and inductance varies, and thus the charging and discharging of the capacitor.

I hope this helps Don, and others. Below is a test I found somewhere, but shows a capacitor being discharded to zero, and over time the voltage gradually rises. This is due to electrons slowly releasing from the insulator instead of instantaneously, and being released when it should not be. This slow releasing occurs for several minutes. In music, the music milliseconds, two seconds, 30 seconds, 2 minutes later is being influenced  by what happened milliseconds, 2 seconds, 30 seconds, two minutes earlier.

Its a real mess that should be addressed if possible.

cheers

steve

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Music Discussion / Re: Sharing Top Notch, Reference Music Links.....
« Last post by Nick B on Today at 10:49:40 AM »
What can one say concerning Jascha Heifetz? Thought this would be enjoyable, especially for those who just wish to hear music, ~3:10.

https://www.youtube.com/watch?v=fJPWWMWkmQA

cheers

steve

Thanks for posting, Steve. Absolutely beautiful and captivatingÖ for those interested, I have posted a link from Wikipedia. I was curious what violins he preferred and that is described. Itís also interesting that he owned the first Electricar on the west coast (18:10 in the video)
https://en.m.wikipedia.org/wiki/Jascha_Heifetz
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Music Discussion / Re: Sharing Top Notch, Reference Music Links.....
« Last post by steve on Today at 06:46:22 AM »
What can one say concerning Jascha Heifetz? Thought this would be enjoyable, especially for those who just wish to hear music, ~3:10.

https://www.youtube.com/watch?v=fJPWWMWkmQA

cheers

steve
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Bipolar System Disorders / Re: I think my System is finally finished
« Last post by Nick B on Today at 12:40:05 AM »
This is great stuff  :thumb:  To what extent I could determine some of the very small changes being described here, I donít know, but it sure would be fun trying to find outÖ

What would also be fun is to have is a CD of recorded music/sounds that would allow comparison of different caps, resistors, types and purity of wire, etc. Donít know if thatís doable or that Iíve seen something like that, but it would be a great companion disc to have.
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Bipolar System Disorders / Re: I think my System is finally finished
« Last post by steve on October 24, 2021, 11:02:03 PM »
When I was in college I spent time working as a photographer. Whenever possible I would use a handheld incident light meter instead of the camera's reflective light meter. The cameras meter measured the light bouncing off the subject and assuming the amount of refection in an average mix of colors it estimated the amount of light falling on the subject. This is OK if you are just looking for acceptable pictures as film has a range of exposures that it will work with. However; using the incident light meter I could measure the actual amount of light falling on the subject instead of estimating it and this allowed be to precisely set my exposures down to a quarter of an f/stop. Yes you can get an OK picture with an estimated reading from a reflective meter, but when you dialed in that exposure dead on the resulting pictures just had a pop to them that I could never get using just the in board camera meter.

It is the same thing with electronic design. It is fairly easy to get an OK design, but when you put in the time, effort and experience to get it just right, you are in a whole different world of performance.

Great example from a different field that is easy to digest. Thank you T.

steve
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Album Reviews / Re: What are you listening to right now?
« Last post by tmazz on October 24, 2021, 09:13:50 PM »
Bruckner: Symphony No. 3 - Haitink/The Concertgebouw Orchestra of Amsterdam



HDTT DXD
Just posted in the RIP thread- Bernard Haitink died 10/21/21 at age 92.

Wow, that's the first one of his albums that I ever listened to and I did not realized that he had just passed when I picked it out.  That's kind of freaky.
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Bipolar System Disorders / Re: I think my System is finally finished
« Last post by tmazz on October 24, 2021, 09:12:08 PM »
When I was in college I spent time working as a photographer. Whenever possible I would use a handheld incident light meter instead of the camera's reflective light meter. The cameras meter measured the light bouncing off the subject and assuming the amount of refection in an average mix of colors it estimated the amount of light falling on the subject. This is OK if you are just looking for acceptable pictures as film has a range of exposures that it will work with. However; using the incident light meter I could measure the actual amount of light falling on the subject instead of estimating it and this allowed be to precisely set my exposures down to a quarter of an f/stop. Yes you can get an OK picture with an estimated reading from a reflective meter, but when you dialed in that exposure dead on the resulting pictures just had a pop to them that I could never get using just the in board camera meter.

It is the same thing with electronic design. It is fairly easy to get an OK design, but when you put in the time, effort and experience to get it just right, you are in a whole different world of performance.
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Bipolar System Disorders / Re: I think my System is finally finished
« Last post by dflee on October 24, 2021, 06:27:50 PM »
"Here is a clue. One can obtain the same/similar specs by using a variety of parts types, and parts value. However, only one part type and value of each will give the most accurate music."

My head just exploded.

Don
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Album Reviews / Re: What are you listening to right now?
« Last post by James Edward on October 24, 2021, 05:16:18 PM »
Bruckner: Symphony No. 3 - Haitink/The Concertgebouw Orchestra of Amsterdam



HDTT DXD
Just posted in the RIP thread- Bernard Haitink died 10/21/21 at age 92.
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Music Discussion / Re: The RIP Thread
« Last post by James Edward on October 24, 2021, 05:14:10 PM »
Bernard Haitink- Dutch conductor and violinist. Oct 21, 2021.
Not as famous as some others, but Iíve heard his name and work many times throughout the years.
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