Distortions

Hi 3D Sonics

[[ Hmmm. So, if all distortion is objectionable, have you had your ears re-modeled yet? And what are you using to play music? In any audio system they are demonstrably the highest contributor to distortion (around 30%+ THD for the ears mechanical system @ 92db/200Hz), followed by speakers. ]]

This is your great argument?... But you are forgetting that the inherent distortion of our ears are our reality.When you go to the concert hall , the sound you hear is your reality even with the distortion inherent of your ears...and any departure from that "sound" will be a lack of fidelity (distortion).



[[ Tell that to Prof. Dr. Hawkesford and Paul Mills. And please them in the JAES where they published their articles on the subject in the 80's. They demonstrate quite comprehensively what the reality is. If you disagree with them, please correct their error in said publication, if you can that is.]]

I know the work of Hawkesford and of course I'm not folowing everything he think.But I find interesting the output stage with error correction , that has been ripped off by Halcro , in his amplifiers.
For the people here interested in some of this work (Hawkesford) see:

http://www.essex.ac.uk/ese/research/audio_lab/malcolms_publications.html




[[ Then perhaps it would benefit you if you made sure you are aware of comparably recent (eg post 1930's) developments in the field of audio engineering. At the very least it saves egg on your face if someone chooses to expose your ignorance.]]

Ignorance, is to believe that since 1930 to ours days there are no developments in audio engineering.
Certainly you are still using a gramophone , as source in your system!

Give me a break!

Big steps in audio Since 1930 and you certainly are saying 30 , because you think that the invention of the Negative Feeddback by Harold S. Black in 1927 is a milestone...or not?

In 1937 Alan Blumlein introduce the "partial triode operation".That later Hafler and Keroes introduce as Ultralinear Operation.

Near 1950 the invention of the transistor in the Bell Laboratories...is this also for you a back step?

In the same decade , the use of the pentode , as output tube that permit higher gain enabling even more feedback for reducing distortion ....or that is bad?

The introduction of Stereo...or you are listening still in Mono?

In the same decade Peter walker build the first and the best of all time electrostatic Loudspeaker ( the 57 FRED ).

1983 the invention of CD in the multibit form , with some years later the great backward step , the introduction of Bitstream ...or for you the vinyl is still the best?


So I feel that ours perspectives are so different that I fell that I'm loosing my time here and I have more interesting things to do.

So be happy hearing your current drive full range , certainly drived by a SE (pentode for current drive...)and with a NOS Dac , without opamp as I/V.

I will continue to hear my crappy solid state amplifier with my DAC with a NE5532 as I/V. :MILD:

FOR ALL.

Try to pass a test CD , with a 0dB recorded signal in your NOS DAC and do as Isaac , inspect with a scoop at the output of the DAC ...you will be surprised!

Passa bem!

Jorge

 

Hi,

Where is the contradiction?

You still do not percieve reality. You preceive an interpreted version. Interpreted by your brain and heavily distorted by your ears.

The type of nonlinear distortion exhibited through low order HD will make fairly little impact on a single impulse and it's form. And it is something I know.

Bottomline, single number "measured distortion" says nothing about audibility of distortion and "lower measured THD" is not the same as "less audible". That is my point anyway.

Ciao T

 

Hi,

What is there was a "NOS" sound but it was not the result of the presence of one type of distortion but the result of the ABSENCE of another type of distortion?

Ciao T

 

Jorge

 

Hi,

I save myself further comments on the rest. If you actually know the facts, why do you constantly make counterfactual statements? Either you do not know or you deliberatly, knowingly make statements that run counter to fact. Why?

Yup, they will be surprised. Because if their DAC is set up correctly they will see this:



This is an actual measurement of a 0dbfs signal applied to a non-oversampling DAC using TDA1543 that is set up correctly for 9V supply and maximum Voltage output (very slightly below 2V RMS for 0dbfs).

This illustrates that "it can be done".

Here a 0dbfs 20KHz sinewave:



Here a dithered -90db tone, showing significant distortion but all 2nd harmonics:



The results of an FFT analysis of a 0dbfs tone BTW shows that designer failed to set up the DAC for lowest distortion at 0dbfs:



This may be intentional as -50db THD at 0dbfs should only effect short peaks and if the level is reduced by only around 12db lower (done by stereophile unintentioanlly by applying a 600R load) which in turn is more closely related to highest average levels on CD linearity is quite good:



The above 2 plots suggest that as set up in the specific DAC measured by Stereophile a 0dbfs signal is just at the limit of hard clipping.

Anyway, if things do not look like above, someone goofed in selecting the resistors for I/V and Reference.

Ciao T

 

Sure, but you wouldn't be able to tell which was the NOS DAC and which the DAC64 . If the NOS DAC had "clearly audible distortion" then it should be no problem to always pick it out of the lineup, what I'm saying is that I seriously doubt you'd be able to do that.

Michael.

 

Let's do it... use your DVD player as CD source...

Remember, "clearly audible distortion" doesn't necessarily mean unpleasant in short term listening... but you'll end up get tired of it more quickly...

 

Sometimes I wonder if listening to music for you HiFi-freaks just is a neccessary evil to enable you to estimate the quality of your kit.

 

'YOU hifi freaks' pe-zulu?

hey, you have 117 posts on a hifi forum!

 

Well, my post is about music, not about HiFi.

 

Using my DVD player as a comparison is not fair as it will be easy to pick it out as the inferior source every time so you'll be able to claim that you were identifying the NOS DAC because of its distortion. A good comparison CDP would be a CDP that uses the TDA1543 but with an output filter. In any case, tomorrow I don't have any time at all.

Michael.

 

Yes pe-zulu... that's how crazy we get when we so desperately seek realism from distortion in our audio equipment...

I still enjoy music in my car stereo though... and I never complaine about it because when I'm listening to it I just know it is the sound of music through a car stereo which my ears are so used to...

It is only when we seek for the realism that will put us more close to the music that we actually start to get away from it... sad isn't it?

At least that was what I thinked until I've listened music, I mean real music, in Tube Dude's system... the music is just so real!

You are a fortunate fellow as you don't care about Hi-fi, but I am even more fortunate because I know what real Hi-fi can do for you and for your music... I wish it was my system.

 

I wouldn't say that I don't care for HiFi at all, but my modest Naimkit fits perfectly for me, and I really want to spend my money upon music rather than investing them in the latest finesses in HiFi. In fact you can upgrade ad infinitum.

 

Michael,

I happen to own an old CD player with the mentioned DAC, that isn't currently being used.
(Actually, I think I own a second one, but am not sure if it uses TDA1543 or TDA1545. This one isn't also being used.)
You can have it borrowed any time you want for comparison purposes.

OTOH, and as I've posted in a local forum, there's someone who owns a TDA1543 CD player, which has been tweeked in order to include a chip allowing it to be used with or without oversampling (same as your DAC, AFAIK), depending on a jumper position. That player also has a digital-out connection, allowing the use of an external DAC. Actually, he also frequents this forum…
I suggest you contact him. You can either visit him or invite him at your place.


Later,

J