John Curl's Blowtorch preamplifier part III

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What I wonder about is how this would be audibly perceived?

I have believed that one single barrier for the solution of the big issue in audio would be 'would it be audible?'. I don't know how this will be solved but i think you have worked with blind tests and designing amps too, so you might have methods i don't know. In my amps i can put a pot which will affect only one variable and i can hear clearly how sound changes.
 
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And so do you

Dispersion (Directivity)

Speaker Off Axis: Dispersion Specifications and Off Axis Response Plots - Acoustic Frontiers

Loudspeaker - Wikipedia

At the same time and to the contrary of what you theorize, there is no term f in the Newton-Laplace equation.

Vaccy,

We are going to disagree on this one. I can find lots of folks who use dispersion for coverage. Doesn't mean it is right.

Acoustic dispersion - Wikipedia


Best example of dispersion is a prism.

As to velocity of propagation Speed of sound - Wikipedia

Density is not the only factor. I suspect you can get good clean measurements of the differences as close as 50 feet compared to 4 feetish.
 
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Robert, here is an inside picture of a CTC Blowtorch with a Vendetta phono stage added.
The white wires are the silver ones, for sure, and they are NOT coaxial, just single hookup wire. Most of what you asked is on the circuit boards, that are thick copper traces with a clear advanced solder mask. Everything electronic is pretty well contained on the individual circuit boards, including power supply buffers and servos.
 

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Don't get excited this is just a response to your repeating issues you took your own interpretation on before.

Sorry enough for now you don't answer any of my questions, BTW does the current flow in both leads of the source or not when you close the switch, speaking of one's own interpretation?

I just did the computation for 10m of RG58. Where do you think the 50 Ohms comes from? 100pf/m and a propagation velocity of 2/3 c (close enough) you don't even need to know L/m you can compute it. Gee the characteristic impedance is 50 Ohms, surprise. 10m is about 50ns.

Now take a 1V battery and close the switch 20mA flows. Lets see how much charge we have when everything stops. Q = CV that's easy 1nC, but 20ma flowing for 50ns is also 1nC, surprise again. OK on to the energy stored in the cable, 20mW for 50ns is 1nJ, but L/2 times 20mA squared plus C/2 times 1V squared also equals 1nJ, more surprise.

Why do I use R/L/C, and Vprop because that's all you need.

BTW I don't care about your microphone problem, IIRC you put up pictures from your OWON scope of 10mV dead zones in sine waves claiming something.

The issue we started with was tapping a microphone to start it working.

No you started it 2 days ago.

I was trying to start a discussion about the reality of wire and cables.
Now how many here have a loudspeaker cable run of more than 10M?
 
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Vaccy,

We are going to disagree on this one. I can find lots of folks who use dispersion for coverage. Doesn't mean it is right.

Acoustic dispersion - Wikipedia


Best example of dispersion is a prism.

As to velocity of propagation Speed of sound - Wikipedia

Density is not the only factor. I suspect you can get good clean measurements of the differences as close as 50 feet compared to 4 feetish.

When a word is used in a particular meaning by experts such as Neumann, JBL, and any other googleable quantity, except by you, to mean the horizontal and vertical coverage of a sound source, whom to trust?

I don't argue that acoustic dispersion doesn't exist when the medium (air) displays non-linear behaviour.

Two things here. First of all, I doubt that these non-linearities occur in the normal course of sound reproduction. Maybe in horn throttles. But secondly, what it could only conceivably do in such extreme and in all likelihood non-existant situations, is to introduce a gradual phase shift with frequency. Nothing to worry about. We are not sending information using coded square waves through air that have to be detected and decoded at the receiving end.

Since it is such a non-issue for audio, the use of the word 'dispersion' in acoustics is generally (and thus, correctly) used to describe the 3D characteristics of a loudspeaker. These, as we all know, are heavily impacted by frequency.
 
Since you can’t do a simple loopback recording correctly, I am curious to know how you have been measuring this current noise.
I can and have made technically correct recordings and they are in the folders/files posted, you have just seized on a couple of recordings that were not 'perfect' in order to bolster your 'argument' which is based on coarse 'theory'.

My determination of directional characteristic is by swapping cable directions and listening....the sound changes follow cable changes, and both channel cables exhibit the same effects, ie there is nothing wrong with the interconnects. The fact that image centre shifts sideways according to channel cable direction confirms that there is directional/asymmetric characteristic. FR is not affected, I determine empirically that subtle noise behaviour is the culprit which could be result of directional scattering behaviour. I could be wrong about this 'theory' of cause for observed sonic changes, but the point remains that there is some kind of directional characteristic in most standard cables.

Dan.
 
The fact is, you have no clue what you are doing.

Now that we have established that you have only heard this supposed phenomenon and then invented some crackpot theory using words you do not understand, we can all move on.

This could be easily measured, if it were true.
 
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Okay, suppose you take a wire, fold it in half, and cut at the fold. Now there are 2 wires each pointing in the, shall we say, opposite noise direction. Solder them together like that in parallel. Does the directionality of the parallel structure then cancel out?
Yes, and this is one feature of the TS/GC loopback cable used. Goop makes directional effects of standard cables more obvious, and also makes more obvious that the TS/GC cable is indeed essentially non directional. Fold in half and cut is how I 'discovered' directional effect in coax/shielded cable hardwired to my TT....this led me on a merry chase until I was shown the effect as I described in a previous post.

Dan.
 
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Like the brightness of silver wires John? BTW, T very politely asked you a question about that, do you have a reply you feel you can share?
Yes, try listening to some silver cable and you may 'discover' something for yourself.
I now have loopback recordings that illustrate this 'brightness', who cares what 'theory' says when the facts are clear.


Dan.
 
... My determination of directional characteristic is by swapping cable directions and listening....the sound changes follow cable changes, and both channel cables exhibit the same effects, ie there is nothing wrong with the interconnects....
Sorry Dan, wrong assertion. The interconnects may be accepted as normal, but there is at least something wrong with them, most probably due to the crappy RCA connectors, try BNC or better direct soldering.
... This could be easily measured, if it were true.
Perhaps not so easy for you and I, but I'm quite confident that Pavel can. :D
 
The fact is, you have no clue what you are doing. Now that we have established that you have only heard this supposed phenomenon and then invented some crackpot theory using words you do not understand, we can all move on. This could be easily measured, if it were true.
You have no real clue about audio or the results that I am achieving. So a couple of files were bunky but not fatally, so what ?. You have not indicated that you have auditioned any of the other loopback recordings, suggest a track you know and like and I will process it for you. My next round of loopback recordings should capture directional effects and stand as proofs. Then we can debate the causes, in the meantime you could try reversing one interconnect and try the experiment for yourself, that is if you have a stereo worth listening to (IIRC you have a little Bose satellite system, is that right ?).

Dan.
 
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