'Audio Lies'

[Christer]

You were too quick Charles, responding while I was editing my post.

I trust you on the summation of RMS values. I don't know enough about this myself, but I have also questioned how superposition works for multiple frequencies. However, does this solve/eplain the problem with instantaneous values?

 

[phase_accurate]

However, does this solve/eplain the problem with instantaneous values?

Aaaaaah - I see what you are questioning !

The solution of this problem lies in the fact that only instantaneous power is related to instantaneous voltages.

But electrical energy (generated/transferred/consumed) is related to the RMS voltage so there wil be no discrepancy in the end.

But the whole thing has an interesting aspect: While the summed RMS voltage of two different-frequency sinusoids with same amplitude is only 1.414... times as high as the RMS voltage of a single one - any device processing them at once has to be capable of processing the peak sum of both ! That's where active crossovers offer relief to poweramp output voltage-swing !

Regards

Charles

 

[jneutron]

Re: A^2 + B^2 unequal (A+B)^2

I had a deeper look at John's posting regarding the missing 2AB.

I now see what is wrong with it. He makes the wrong assumption that the audio signal follows the sum of the acoustic powers and therefore at every point down the audio-chain we would have a scaled version of the sum of acoustic power again which can be split back into seperate powers by simple linear operations.

It is not that simple though:
The signal-voltage represents the sum of sound-PRESSURE levels.
There are the same relationships between sound-power and SPL as there are between electrical power and voltage. That means for the same circumstances power raises with the square of the RMS -voltage/-SPL !
So far so good.

What happens if we now add two sinusoids of different frequency ? Is the RMS voltage of the two added signals of RMS value A and B now A+B ??? No it isn't !!!! Since they sum UNCORRELATED their new RMS value is:

SQRT(A^2 + B^2)

Now check by yourself if you would still get a missing 2AB !

BTW: If John's observations were true they would indeed have nothing to do with cables as such but they would occur in every single little part of the whole chain !

Regards

Charles

Would you please post under the new thread? Thanks.

I'll put my response over there, with your post quoted..

Cheers, John

PS..Christer is correct, I am not speaking of rms.

 

[peranders]

I seem to have missed this thread or repressed it Better not to say anything. I think quite many of you know what I think.

I love this: Dark looking amp sound dark, and bright looking amps sound bright.

 

[mikeks]

When it comes to loudspeaker woofers, I am not so sure.
They are mechnical constructions that are moving.
Maybe the suspension can change some after some use.

True..

 

[lineup]

.

posted by darkfenriz
> I think how many make their living from these lies or truths being still unanswered.

No doubt there are many making a living out of it.
Telling not only lies, but a mixture of half-truths, lies and good facts.
If it were only lies, it wouldnt be hard to tell.

Think the only defence from being scammed or unintendely mislead by somebody
is to try to define what is good facts, to you your self.
Just follow the direction from others without some filter of your own is no good,
does not matter if those directions are lies or good useful information.

I have a few persons, who I trust in Audio,
from which I could take a good advice or two, without questioning.
Because I know they have done some evaluations
before they state their findings.

But even then,
if a trustworthy person is telling me some strange illogical thing,
I would have to make up my mind doing some research of my own.
Or compare to what others may have found.


lineup discussing matter of truth and lie is never easy
any concept that is not easy to define in simple way, is hard to fully grasp and to debate
what is love?
what is evil?

 

[classd4sure]

Right,

Fools get taken, educate yourself, through research backed by, experimentation, and experimentation backed by research. It becomes easy to spot scams or the people selling them.

So if we then value either fact or fiction, which I sure hope we do, we're here to share, educate "ourselves", in order to guard ourselves from scams and those who push falseness for the cost of our dollars.

I think there becomes a deeply inherent desire to then stomp on such ignorance when you see it peddled here.

Some are so flamboyant with it there ought to be an award given regularly for such a thing by way of a permanent thread, called wall of shame.

 

[poobah]

Couldn't we call it the Nugent Award?

 

[classd4sure]

Skidrow SuperSTars? See the show?

 

[poobah]

We have emmys grammys etc... How 'bout a Phooly?

 

[lineup]

I find it amusing that he says that Golden Ears don't exist...then that they do.
How typical.
//--//

Grey

Hi.
Regarding if some people (golden ears or who ever)
hear something else or something different, than others,
me, Lineup, say this: There is NO DOUBT about it.

Not only do we percieve, experience sounds on an individual & unique basis.
Any sensory perception, like taste, visualisation, colours, skin touch feel, smelling can be differently experienced.
This has to do with DNA and also Interpretation of perceived sensation.
This fact does not 'prove' or 'verify' that anything that audio people say that they can hear is true.
Far from, as we all may know

But my bottomline is in line with Mr. Grey Rollins' view:

Lineup, 2008:
- Just because you personally can not hear or
do not think you or anyone else can hear subtle things,
when listening to sound waves as e.g. music
... this doesn't automaticaly mean that
- no body or no mind can percieve such subtle things.

We know from reality, that Blind Musicians and those with very bad eye-sight can See More with their Ears.

We also know, that some people in Music Can exactly Know a pure tone. Say the tone 'A', 444 Hz.
I do not recall what this is called in english, but in swedish we use the expression we have gotten from Die Deutsches / German language ( swedish are at much a germanic people from the north of europe):

Absolute Gehör - Absolute Gehoer
- absolute, as in definitive
- gehoer ~ ge-HEAR, as in hearing

This is what great composers in history have had, like Johan Sebastian Bach.

Absolute Gehoer!!
This is not the common case. This is a special gift some have - other do not have.

Lineup

 

[Ron E]

We also know, that some people in Music Can exactly Know a pure tone. Say the tone 'A', 444 Hz.
I do not recall what this is called in english, but in swedish we use the expression we have gotten from Die Deutsches / German language ( swedish are at much a germanic people from the north of europe):

Absolute Gehör

It's called absolute pitch (or perfect pitch) in english. Probably has very little to do with "golden ears" and more to do with training. You can't identify something as A if you don't know what "A" stands for. Many musicians and others have do not have absolute pitch, but have perfect relative pitch.

Ever think that perhaps the blind hear more because they are not distracted by eyesight?

Oh, and BTW, in your signature, Standpunkt means "point of view".

 

[lineup]

It's called absolute pitch (or perfect pitch) in english.
Probably has very little to do with "golden ears" and more to do with training. You can't identify something as A if you don't know what "A" stands for.
Many musicians and others have perfect relative pitch.

Perfect pitch or absolute pitch.
Thank you.

Yes, training makes perfection .. eventually.

To a certain degree it is very good if you are born with specific
setup of quality.
A base quality, to enable make you to be a REAL great footballer.
Like Pele, Maradona or George Best.
Not everyone can become a great musician, composer or aquire perfect pitch hearing,
just by training alone.

People are born different.
This goes for hearing sound qualities, too.

 

[KSTR]

I agree that especially absolute pitch is also to a big part a matter of training. While I cannot sing or hum a tone with great precision, I today can tune an new guitar to about 1/4-tone max error from scratch (when checking with a precision tuner/fork). I've been training that for some 35 years now.

Nonetheless I know a semi-autistic (and 95% blind) recording engineer that beats my hearing abilities (on that topic as well as in general) by lightyears....

- Klaus

 

[lineup]

Friendly Advices at this forum,
sometimes says, we should do burn-in period.
-

From this I can conclude some of us think components in amplifiers
need to burn-in for a time.

Me, Lineup
I still dont think anything in an amplifer need to burn-in.

This is not to be mixed up with 'warming up'.
For example in Class A amplifiers takes some time
before component temperature settles at working level
and current levels get stable without too much drift.

... and then we have the Burn-Out factor
.. previously mentioned in this topic
.. when things get worse after a period of BURNING

 

[jan.didden]

I agree that especially absolute pitch is also to a big part a matter of training. While I cannot sing or hum a tone with great precision, I today can tune an new guitar to about 1/4-tone max error from scratch (when checking with a precision tuner/fork). I've been training that for some 35 years now.

Nonetheless I know a semi-autistic (and 95% blind) recording engineer that beats my hearing abilities (on that topic as well as in general) by lightyears....

- Klaus

Klaus,

Generally, perfect pitch is something people are born with, and can demonstrate already at very young age. Of course, somebody needs to tell you that a specific pitch is, say, A, before you know that. But the ability to recognize or produce perfect pitch is in-born.

Jan Didden

 

[bulgin]

"Audio Lies"

Hi

So, with great anticipation, I installed the Quasar MC1 on my sme V and put some tried and trusty songs from the Knobbly Kneecaps' spring of '72 album on the platter.

And what a let down, folks.

The cart literally screeched, whatever bass was there was soft and ill-defined. BUT, being the kind soul of a reviewer, I decided to persevere.

Hour after hour I spun them vinyls. Mrs Kossler first ran out of beers. Deep in to the night it went. Around 4am of day 7 I sent the missus out for a plate of samoosas and raspberry shakes.

After scoffing the lot, I made a pitstop and checked the oil in the 301's bearing well, re-adjusted the VTA, SRA and VTF.

Ah checked my Braytling ZeroTime-master GMT's elapsed time counter, which showed exactly 100 hours gone and let fly with anodder disc.

What a revelation! The Quasar MC1 had miraculously opened up. Inky black blacks, wide soundstage, superlative mids.

Just goes to show. Carts need to be played to death for at least 100 hours before ya kin hear the difference between 120 dollars and 5'000dollars.

Will this do for another "Audio Lie"?

bulgin

 

[lineup]

Cable Cooking for delicious musical dinner

How much more open did it sound?
2-3 meters?
15 % ?
Twice as open?

( Of course you used blind test, to exclude you all there biased each other. Anything else wouldnt be wise. )

You're a good man Line-up...

poobah,
What do you know about how good I am?
I may be one notorious swedish serial killer. To be discovered soon.

By the way, what is your new second alias here at diyaudio.com?
Because I can not really believe you can go from 10 posts per day down to 1 post every second month.
There is something hidden here ......

An externally hosted image should be here but it was not working when we last tested it.

CABLE COOKER[tm]
The Cable Cooker[tm] speeds up burn in of signal-, speaker- and power cables.
Without making any sounds!
You should observe correct direction of cables. From input to output.
If we are to believe feedback from buyers, they are very please with results.

I simply use my function generator + two LM3875 at 1 kHz for 14 days or so.
To avoid the sound I attach cables with dummy load resistors 8 Ohm.
And I mark my cables for preserving correct direction of sounds.

Anybody else but me does Cooking his Cables?
Using the above machine or some other device?


Lineup - Cable Cooking for delicious musical dinner

 

[scott wurcer]

Part of the burn in proceedure should require listening to the entire process to ensure the proper conditioning of the listener. Directionality of the listener is of course a personal choice.

 

[lineup]