Passive I/V vs. traditional I/V, FFT pics.

[Bernhard]

Did you compare left & right channel of your cdp ?

 

[A 8]

Did you compare left & right channel of your cdp ?

Yes, they are identical between L&R channels irrespective of the source; Denon DVD 2900, Sony CDP or wav files direct from the computer.

 

[ojg]

PThe pic below shows the passive balanced PCM1704K @ 0dB and a analog attenuator before the soundcard....still looks better then expected.

It is very good indeed! With your solution you have combined I/V, preamp and volume-control fully balanced in one single potentiometer, quite nifty! I assume the pot is about 1kohm but at normal listening levels it is probably not set at much more than 100ohms, right?

Too bad I did not realize this until Pedja's post, but it is obvious now that your original -60dB signal was un-dithered.

 

[A 8]

ojg,
That's about it but I use a stepped attenuator.

I had to test 24 bit performance and made a few dumps of -100dB, -110dB, -118dB and digital zero still at the poweramp (2*180w) output.

Pretty impressing as well.......

The small spikes @ 4.3, 14 and 18kHz seems to be from the computer/soundcard combo as they are identical if I just short the input on the soundcard.

First out 24/48@-100dB

 

[A 8]

24/48@-110dB

 

[A 8]

-118dB...I guess the TDA1541 would have a hard time matching this

 

[A 8]

And digital mute just to show I wasn't just lucky getting the -118 reading.
Also shows that spikes orginating from somewhere else but the dac/poweramp combo.

 

[A 8]

BTW, it sounds really good too.

 

[Bernhard]

-118dB...I guess the TDA1541 would have a hard time matching this

For those of you who can't resist getting into a ****ing contest I suggest you save your TDA1541/nonos vs everything else for another thread.

Seems the distortion is hidden under the noise.
Also such low signal level doesn't exist on CD ?

Want a DAC shoot-out ?

I am seriously interested if more bits are better

Please post new measurements @ -60dB with clean signal from Pedja.

I got two -60dB signals, one from Pedja and one from another forum member.
One had lower noise and I don't remember which one.

This is one of my 1541 with os, don't remember which one:

Worst harmonic is K2 is -65dB

 

[A 8]

Want a DAC shoot-out ?

Sorry about doing what I asked you not to....and -no I am not looking for 24 vs 16 bit dac shootout as a 16bit dac is not an option for me.

Also such low signal level doesn't exist on CD ?

Right, however CD is not the only source availible to us. Concerts on dvd in 20-24/48 LPCM makes a big difference when run through a 24 bit dac vs a 16 bit one and can become very engaging.
DVD-Audio through this dac when mastered right is also VERY nice.

I am seriously interested if more bits are better

Well at -60 dB there might not be a big difference but at -100dB and below there will be a significant difference..