Misleading Measurements

[fas42]

17 minutes ago, bluesman said:

That's a definition I never heard before.  Reactance refers to any force in an electric circuit that opposes change in the flow of current, not the flow of current itself. Your definition (apart from the term inertia) would include resistance as well - but the two are entirely different, even though both oppose the flow of current.

 

A slight correction, if I may, 🙂 ...

 

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Electrical reactance, (is) the opposition to a change in voltage due to capacitance (capacitive reactance) or in current due to inductance (inductive reactance); the imaginary component of AC impedance.

 

 

[fas42]

11 hours ago, bluesman said:

As for having "no mechanical switches in the signal path", I assume you realize that there are SS relays instead.  Although they are free of the arcing and other ills of mechanical switches with contacts, SSRs are also not perfect conductors.  If you look at a schematic for an SSR-switched circuit, you'll find that almost all have some kind of diode or RC shunting across the SSR's output (often within the SSR).

 

IME, SS relays are good ... if the circuit is well designed, any ills of their non-perfect resistive qualities are far outweighed by getting rid of the evils of contact noise in physical switches - as a general rule, the more ambitious the setup is, the more one has to worry about the influence of mechanically operating parts in the chain.

[fas42]

Not quite sure what the fuss is about ... simply put, there is a huge range of subjective average levels with the recordings themselves - I've had systems which completely ran out of gain with some CDs of mine, it was impossible to lift the level above, say, what a TV feels like; yet that same system could have my ears ringing after 5 minutes of a modern pop recording, at a volume setting quite a bit of a way down.

 

Worrying about differences of a few dB in some part of the chain is completely meaningless in the face of this - what one wants is the capability of a huge range of gain settings, without hearing any anomalies at either ends of the range.

[fas42]

On 4/21/2021 at 7:18 PM, stereo coffee said:

Perhaps the most misleading thing is not measuring equipment with respect to recognised standards that the majority of home audio equipment complies with.  If we observe for example consumer line level which is nominal 310mv RMS . .... until they get that right I would suggest ignoring all measurements that fail to understand consumer line level, as anything higher is meaningless with respect to equipment you use every day.  

 

Going back to your original post here ... could you state precisely what you hear, in the music replay you listen to, that provoked you to make that point?

[fas42]

13 hours ago, stereo coffee said:

And no dynamics, and sounding squashed will be the direct result. Why ASR is pushing this agenda is the question to ask, as it has nothing to do with enjoyment of music. 

 

I will start a new thread, as its a fascinating subject, there i will provide answer to what is needed.  

 

 

Why playback can have no dynamics and sound squashed is a combination of the way the particular recording was mastered, and using a flawed playback chain - it has nothing to do with signal levels, in the sense that you're talking of them.

[fas42]

Just bumped into this, on ASR ... https://www.audio “science” review/forum/index.php?threads/things-that-cannot-be-measured.20808/post-690068

 

By member Sawdust123 there, who just happens to be this chap,

 

 

Considering he's in the AP world, I suspect he knows a thing or two about the subject ... bits of a couple of recent posts,

 

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The point of mentioning all this is that we already have the science that explains why transient responses will be different than steady state responses yet the vast majority of our testing is steady state.

 

and

 

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I sold audio test gear for 15 years and sat on standards committees too. In a nutshell, we measure what we do because we can do so easily. It is my opinion that we can get A LOT more from instrumentation but choose not to because the financial reward for doing so is not there.