I guess filterless non-OS is a bad idea

[regal]

http://recforums.prosoundweb.com/ind...t/13252/15828/http://recforums.prosoundweb.com/ind...t/13252/15828/

I didn't know I could damage my equipment by running by nos-dac into my headphone amp. I thought it sounded good too, but I must be wrong.

[jean-paul]

Now I digress, to the DAC AH that is a non oversampling DAC using 8 TDA1543 chips with no digital filtering. From our discussion above one would assume that the grunge left over should have blown up tweeters and mylar alike. But, that’s not what happens. So what gives?

This has to do with the 8 TDA1543 that the DAC AH employs and the algorithm used for designing non oversampling DACs. The non-OS algorithm by definition introduces a slight roll off in the treble, so by the time you get up to damaging frequencies, the output of frequencies above 22kHz isn't really all that high. Hence, intermodulation distortion still makes its way into the DAC AH and other non oversampling DACs. This may explain why some non oversampling DACs sound compressed at the higher frequencies. The DAC AH modded, less so, only because the superior OP AMP compliments the conversion process in that it is able to open the sound a bit. Some NOS DACs add a digital filter – but that really defeats the whole purpose of the NOS DAC anyway – its kind of like adding MSG to a low salt diet.]

Just some info my friend Google showed me in 1 sec.

If you manage to damage your tweeters with playing music at moderate to even quite loud levels you'd probably the first non os victim.

[phn]

There are bigger "threats" than non-os out there.

Not all sound systems may be able to cope with the high frequency energy that accompanies a DSD recording. Reports suggest that some Mark Levinson gear, for example, has failed as a result. It has been debated whether or not this is due to actual high-frequency signal content, or to the presence of high levels of out-of-band noise produced as a result of the heavy noise-shaping curves employed in DSD. It is also highly likely that claims of potential damage are greatly exaggerated. In any event, the Philips SACD1000 includes a rear-panel filter switch to deal with possible problems. According to the manual, the three positions offer a 40 kHz rolloff, a 50 kHz rolloff on the front speakers and 40 kHz on the others, and 50 kHz rolloff all round. This seems a little odd: one would have thought that an extra 10 kHz wouldn’t make much difference between your system working and blowing up, and indeed the data sheet for the product refers to "filter on" and "filter off" responses, the former going up to 40 kHz and the latter 100 kHz, which is more like it. My very ordinary system did not fail in any position. I might possibly have noticed a little more high end on high frequency instruments like triangle, bells and stuff as I switched between 1 and 3, but equally I could be fooling myself.

http://www.avrev.com/equip/philipssacd/index.html

[rfbrw]

Originally posted by regal
http://recforums.prosoundweb.com/ind...t/13252/15828/http://recforums.prosoundweb.com/ind...t/13252/15828/

Nice place. No time for nossers.

[jean-paul]

Hi rfbrw, did you check the result of your remarks here:

http://www.diyaudio.com/forums/showt...19#post1006719

[rfbrw]

Originally posted by jean-paul
Hi rfbrw, did you check the result of your remarks here:

http://www.diyaudio.com/forums/showt...19#post1006719

Praise ye the Lord, a sinner repenteth.

[jean-paul]

The right conclusion ( in the eyes of the spanish inquisition ).

[rfbrw]

Originally posted by jean-paul
The right conclusion ( in the eyes of the spanish inquisition ).

With a name like yours you should know.

[Russ White]

Originally posted by rfbrw


Praise ye the Lord, a sinner repenteth.

sometimes I am thick... But I usually come around.