60 chip DDDAC1543 Mk2 vs TentLab DIY DAC

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So what else shall be true ?
I don't know..I just question the fact that those who enjoy the TDA1543 enjoy it BECAUSE of the distortion.

How do you define TONE ?
Good question. I suppose one can't define it. I know what it is for me personally... It's when I say.."hey...that sounds just like this or that instrument." I know one can distinguish between instruments on basically any piece of hifi...in a manner such as s..thats a violin..that is a piano...but I mean one step further...not like the real thing....but WOW that sound ALMOST exactly like a real violin. Maybe the uncanny ability to do that is actually a function of non-oversampling..I don't know.. because I have not heard any other chip without oversampling.
 
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After so many people are speculating on my designs, let me give you my input on why I use the TDA1543 implementations I made (the mk2 so far)

1. 1543 can give almost 2V RMS output at low impedance without adding expensive transformers or tube stages.

2. distortion? My SE amp distorts 3% ......

3. by paralleling the backdrop of the 12 bits non linearity vanishes

4. I think it sounds so great, as there is NO oversampling and digital filtering.

5. The emails I receive back (and that is double digit plus) of people who built the dddac1543 are all MORE than satisfied and that is an understatement.....


If you want better sound, you can get it for sure, but at a multiple of cost and a multiple of energy.... If I sent a dddac kit, sometimes people react within 48 hours telling how great the DAC plays !

This all is for me also a very important part of DIY.... Let the real MASTERS do their own thing and built better stuff. That is their good right. But most of the people outside, just want to have good music and have no laboratory at home to do all them selves.... what is wrong with that ?

My Opel Omega drives fine and does also 250km/hour. Are there better cars? yes !! But stiil I move my self with full satisfaction from A to B over the German Autobahn :D

Doede
 
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It’s been a long time – I could’ve forgotten couple of things….

What happens when you feed the AC trough the capacitor? (let’s start with single frequency AC)

The output is shifted in time for approx 90 deg.

Audio signal is a complex and contains many frequencies whose relation to each other helps us humans determine the position of each individual instrument / voice in front of us.

Send the signal trough more than one capacitor (placed at two different places in a signal chain) – and this correlation is gone forever!!!

Each individual capacitor shifts different frequency spectrum differently – putting them in parallel will add to total distraction of phase (time) - to – frequency correlation. This is why you should only use the capacitor if you absolutely have to – and if you have to then never bypass them – use only one in a signal path.

I have experimented for a long time – paralleling could yield to better perceived tonal character – but the stereo and 3D imaging gets completely lost. This is why Audio Research gear sounds pleasant without really meaning anything… they love to parallel those coupling caps…

Extreme_Boky
 
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Extreme_Boky said:

Each individual capacitor shifts different frequency spectrum differently � putting them in parallel will add to total distraction of phase (time) - to � frequency correlation. This is why you should only use the capacitor if you absolutely have to � and if you have to then never bypass them � use only one in a signal path.


That could be tested. Mix two sines of 100 Hz and 10 kHz together, send them directly to scope channel 1, feed through one cap & send to scope channel 2, feed through parallel caps 10µ and 100n & send to scope channel 3.
 
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Extreme_Boky said:
[snip]What happens when you feed the AC trough the capacitor? (let’s start with single frequency AC)

The output is shifted in time for approx 90 deg.
[snip]


Sorry, have to disagree. The output does not necessarily shift in time. What happens is that the current through the cap lead the voltage by 90 degrees. That shifted current runs into the resistor loading the cap. Since there is no shift between current and voltage of a resistor, the voltage developed across the resistor is in time step with the current through the cap which is shifted from the voltage across the cap. So, the shift between the voltage across the cap (lets call it the input voltage) and the voltage across the resistor (let's call it the output voltage) depends entirely on the impedance ratio of the cap and resistor at the frequency you are looking at.

If your cap is large enough wrt frequency, as will be the case in for instance well-calculated coupling caps, the time shift is very small. In fact, at the -3dB point, where the output voltage has fallen 3dB wrt the input, the time shift is exactly 45 degrees.

If the C and R in a low pass link, for instance, are chosen for, say, a 3dB point of 60kHz, the time shift at 20kHz is in the order of a few degrees.

Jan Didden
 
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Extreme_Boky said:
[snip]Each individual capacitor shifts different frequency spectrum differently – putting them in parallel will add to total distraction of phase (time) - to – frequency correlation. This is why you should only use the capacitor if you absolutely have to – and if you have to then never bypass them – use only one in a signal path.[snip]Extreme_Boky


This is completely in conflict with reality and facts. If anything, paralleling caps makes the time shift (phase shift is the normal term) smaller than it already is. Choose you cap value sensibly and it is a non-issue.

Jan Didden
 
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