New DAC measurement

[Bernhard]

Hi,

not want to torture U, but here an overview of DACs I have in my players.

All same scale and level on K3 referenced to -60dB 1kHz signal.

What I can say is that, compared to 16 bit, 18 & 20 bit does not perform better in distortion, only in noise.
Thus distortion becomes even more noticeable.

Start is PCM64 with optimum distortion adjustment made with multiturn pot in Denon DCD1520.

 

[Bernhard]

My precious:

A no grade PCM56, one of the best out of 50 tested chips of all grades, in Denon DCD 1500mkII, also with optimum distortion adjustment made with multiturn pot.

No harmonics visible.

K3 for example is 6 or more dB better compared to the PCM64.

Others PCM56 chips look very ugly, even K grades.

 

[Bernhard]

TDA1541 one channel in a Philips CD960:

 

[Bernhard]

Other channel:

 

[Bernhard]

My second CD960: Direct comparison of both channels.

This one is unmodded with NE5534 while the first one had 4 x Burr Brown OPA627 & foil coupling caps at the output.

Note that in both players ( chips ) distortions of channels are totally different, good for soundstage ???

 

[Bernhard]

PD2028A, Pioneer bitstream DAC in a Pioneer PD75.
Best so far

 

[Bernhard]

Another bitstream DAC: TDA1547, 1 chip per channel in ONKYO 6890.
Also very good

I once had a Marantz player with SAA???? bitstream DAC, that was bad...

 

[Bernhard]

Now a real state of the art DAC

TDA1540 14bit

Note the subharmonic @ 650 Hz.

Both channels are absolutely identical what is not the case with TDA1541.

 

[Bernhard]

PCM63-K2 in a Pioneer PD8500.
Not very impressing, original J grade chips looked similar.

 

[Bernhard]

Other channel:

 

[Bernhard]

TDA 1541A S1 in CD880, original chip, no silvercrown but Q sticker & S1.

Not so bad...

 

[Bernhard]

Other channel:

 

[Bernhard]

A bad PCM56 with best adjustment:

All odd order harmonics, no wonder some people don`t like it

 

[Bernhard]

For all postings:

The enlightened point on the cursor marks the amplitude of K3.

 

[Bernhard]

A PCM63K from a forum member , looks much better than the other 4 chips I tested.

Worst harmonic is K5 -60,6 dB

 

[Bernhard]

TDA1543 in Philips CD600.

Looks like a 14bit TDA1540 without even order harmonics.

 

[philbyx]

Hello

a measure on mine at -60dB of full scale:

http://www.diyaudio.com/forums/showthread.php?postid=569718#post569718
(before adjusting the ad1865 msb trimmer)

Philippe

 

[philbyx]

And at 0dB :

Philippe

 

[philbyx]

And the last : -80dBfs :

Philippe

 

[Bernhard]

a measure on mine at -60dB of full scale:


(before adjusting the ad1865 msb trimmer)

Philippe,

That means, scaled to how I measure ( -60dB signal is set to 0 dB reference in the analyzer) , you have left channel K3 -40,5 and K5 -45,6. Right channel K3 -44,8 and K5 -55,6.

This is not very good, do you have measurement after distortion adjustment ?

My best PCM56 chips have all harmonics below -62 dB which means -122 dB in your scaling.

Your DAC is non os ? I do not know your chips but i know TDA1541 is getting worse in non os.

Those harmonics will give your DAC a specific sound, only question is if you like it

I prefer the cleanest I can get and I don`t care where it comes from, os or non os. Cleanest I get from os