Microphone cable differences

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In audio, voltage matching is the main method of working. This means Rin >> Rout (rule of thumb factor 10). Most preamps work with input impedances of greater than or equal to 1 KOhm.
If you read my post, you would have noticed that I was referring to the output impedance of the mic preamp. I didn't mention its input impedance because it is irrelevant in the discussion.
The main problem is the interaction of the complex load with the individual factors.
And that's exactly what I discussed.
This is discussed in detail in the books on communications engineering. If I find Ing. Wuttke's contribution in the conference documents, I will post the lecture.
With all respect due to Ing. Wuttke, I didn't learn anyhing from his document. It is a vulgarization, destined to technically untrained public. It's electronics #101.
It doesn't mean it is not true, just that it doesn't go deep into understanding complex situations.
 
If you read my post, you would have noticed that I was referring to the output impedance of the mic preamp. I didn't mention its input impedance because it is irrelevant in the discussion.
Unfortunately, the connection to the output impedance was not so clear in your post.

The input impedance is not irrelevant. Especially for people who aren't that well versed in electronics.

Best regards!
 
Unfortunately, the connection to the output impedance was not so clear in your post.
What's not clear in this :"In practice, the optimum depends on the relative value of the microphone and preamp output impedance."
The input impedance is not irrelevant.
The input impedance of the mic preamp would be relevant only if it was unduly low. It is understood that the mic pre input impedance is about 5-10x the mic impedance.
Especially for people who aren't that well versed in electronics.
Which, fortunately, is not my case.
 
Mr. Wuttke's entire book can be found here and is a useful read. It is the latest edition in pdf format, so it can be copied and easily translated into another language.

https://schoeps.de/wissen/dokumente-downloads/vortraege-und-aufsaetze.html

As for the choice of microphone cables, yes, there are differences. For studio use I would always choose GAC3 or some Mogami cable variants, while for live Klotz and some other Mogami cable variants. Considering that the idea that all cables are the same seems to prevail here, it makes no sense for me to elaborate further.
 
A late reply but, as someone who does a LOT of amps every month I’ve never seen a guitar amp ever where signal hits a tone stack before anything else.

Agreed. But I was referring to the usual tone control internal to an electric guitar or bass ie a RC across the output with R being a variable pot with a fixed C.
 
Who is the intended audience for the paper?
Maybe the dipl. ing. needs to do something to earn his pay?
As I noted, I mean no disrespect to Ing. Wuttke, on the contrary, but the book is not of a very high technical level.
The title of the chapter is Mikrofones Allerlei - kleines Kompendium (Various microphones Small compendium), which clearly expresses the fact that it's not intended to cover the subject in deep detail.
This is typically the type of article that a designer would write, which would bring his company's products visibility.
I've done that a few times, and I never involved heavy math lifting because I new that the public would have ignored it.
 
As for the choice of microphone cables, yes, there are differences. For studio use I would always choose GAC3 or some Mogami cable variants, while for live Klotz and some other Mogami cable variants. Considering that the idea that all cables are the same seems to prevail here, it makes no sense for me to elaborate further.
Nobody said that "all cables are the same", but as can be noted in Ing. Wuttke's book, the dominant electrical performance parameters are very few, predominantly capacitance and shield coverage.
Even these parameters are not deal-breakers; one can use high capacitance cable if the source impedance is low enough and its output capability acceptable. Acceptability of a cable with low shield coverage must be evaluated in the context of length and RFI/EMI level.
As your choices indicate, it seems that mechanical parameters have as much importance. One does not need to have a degree in science to make an evaluation ot these parameters.
 
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It is your opinion.
Best regards!
This is the introduction to the book.
"This article first appeared under the title “Recording technology for the demanding amateur” in Stereoplay, issues 8/9 1988. It was originally aimed at music lovers who, apart from basic physical knowledge of acoustics, have little knowledge of microphones and recording technology."
It shows that this document, although undeniably scientifically true, does not intend to explore complex subjects.
 
This is the introduction to the book.
"This article first appeared under the title “Recording technology for the demanding amateur” in Stereoplay, issues 8/9 1988. It was originally aimed at music lovers who, apart from basic physical knowledge of acoustics, have little knowledge of microphones and recording technology."
It shows that this document, although undeniably scientifically true, does not intend to explore complex subjects.

Great research work.:)
 
The main problem with guitar cables is that the pickups used in the electric guitar, in conjunction with the capacitors and high-impedance resistors used in the electric guitar, form a system capable of oscillation. The capacitive, inductive and resistive factors acting from the outside (including cables) cause changes to this system. It is therefore worth keeping any kind of load as low as possible.

The situation is similar with the amplifiers built into acoustic guitars. These are normally not able to transfer the capacitances that occur via the cable.

Therefore, my recommendation is to keep the cable as short as possible.

And of course, use a cable that is low in microphony and low in capacitance.

Best regards!
 
The main problem with guitar cables is that the pickups used in the electric guitar, in conjunction with the capacitors and high-impedance resistors used in the electric guitar, form a system capable of oscillation.
For it, it would also take some source of energy. What would it be?
The capacitive, inductive and resistive factors acting from the outside (including cables) cause changes to this system. It is therefore worth keeping any kind of load as low as possible.
Can you describe these "capacitive, inductive and resistive factors acting from the outside"?
The situation is similar with the amplifiers built into acoustic guitars. These are normally not able to transfer the capacitances that occur via the cable.
Passive pick-ups built in guitars have low level of power, hence need care for being transmitted properly, but it actually works in millions of parts of the world.
Amplifiers built in guitars help overcoming this issue.
Therefore, my recommendation is to keep the cable as short as possible.
There is no doubt that keeping cables short, in all circumstances, from ECG, ro nuclear plants is good for the efficiency of power transmission.
 
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