the essence of how it works and why is sounds as it does is simply
bypassing the filter.

Just that?, you don't replace the bypassed digital filter with an
analogue one?



Heard of what? If you mean non-oversampled audio DACs I heard of them
about 40 years ago!

Did you? Hey Dave, you make a lot of claims. Now on this subject give
one example of a non-oversampled "audio DAC" from 40 years ago (1970)
that you could have heard about back then. Get googling and try not to be
frantic.

Hi Dave
I wasn't holding my breathe for your example of a 40 yr old NONOS dac.
And I really shouldn't do this, but last night I read through the latest
edition of a HiFi mag, it being the best of the bunch, but disappointing
nonetheless but that's for email.
And this is pathetic of me, I'm a shift worker on lates this week and
I had determined to break from the webby thing for a while but as there
is no "TheWrightStuff" and it's an hour until Trisha, yep I logged in here..
This morning I remember parts of my dream, at least it was about Anne
Diamond and Kirsty Young, but that's for another group. But this morning
the first thing running around in my head is the stuff you Dave come out
with.
Hey Dave, you are an annoying bluffer, your provocative technique is almost
impressive if it wasn't for the fact you don't get your facts right?
You have to admit it was a bit silly to claim you "heard" of NONOS audio
dacs 40 yrs ago, but when this topic started in this group you had never
heard of it!
And you keep referencing a need for analogue filtering when no digital
filter - Totally pointless, and very Wrong!
I've just briefly read through the thread, it seems by time and date of
posts that you only mentioned analogue filtering once Jim and I touched
on the subject? So I'll explain....

NONOS. NON O/S. Non over-sampling DAC:
The point of oversampling as identified graphically many years ago
by PMi is that ultrasonic hash that is just outside the audioband is
pushed up and away in steps - 2x o/s, 4 x o/s etc.
Primarily this is for system compatibility issues, but also back in those
early days of CD, for the issues with the then yet to evolve digital
recording techniques employed or the transfer of analogue masters
to digital (and those techniques to digitally record and transfer to CD
are another very convoluted subject).
Again I'm going to cite PMi, he identified that without digital filtering
that ultrasonic hash may "envelope" back into the audioband, and now
I'm going to cite me again, with the right recording and the right system
(Not an over-priced ugly shoebox of the 80's) that "enveloping" can have
a "magical" effect.
If for the sake of your insisted (but wrong) argument we look at if it
cannot work without analogue filtering - how would that work?
If I bypass pre-conversion digital filtering, and spuraie "envelopes" into
the audioband, then it is there through conversion, there is no subsequent
filtering of any type that can undo that.

Discuss.

PS. So Dave what have you got planned for today, are you into gardening?
Do you live in or near London, interested in hearing a NONOS'd cd player?