Jon Noring wrote:

Patrick Turner wrote:

I won't budge from the idea that its possible to digitise the signal
from the antenna and simply apply suitable algorithms, and get
digital decoding, without all the phase shift caused by consecutive
tuned circuits.

And I agree with Patrick. Despite my desire to have a nice, kit-made,
high-performance AM tube tuner, ultimately I think the best radio
tuner for sound quality and overall performance (whether AM, ASM, FM,
digital broadcast, etc.) is the pure digital system as described by
Patrick.

But do the necessary low-level A-D converters already exist? Is anyone
actually building radios on this principle, or are we still a few
years off?

Jon Noring

There are virtual radios which can be installed in a PC.
Been around for years.
They involve a suitable antenna interface and sound card, and program on a
disc,
and were advertised for sale on the back of Electronics, the british
magazine.
The front plate of a radio communications receiver appears on the screen
and I guess you tune and select receiver functions by dabbing items on the
screen with a mouse.

[p.s., pure Class D digital amps are continuing to improve, with
better switching and so on, so ultimately the only analog streams
we'll be dealing with will be radio signals captured by the antenna
(which will promptly be digitized), and the output to the speakers
from the last-stage PWM of the digital amplifier. Everything inbetween
will totally be digital, using advanced and inexpensive DSP to do
things not possible in the analog processing realm. The only realm
left for the audiophiles to play in will be speakers.)

I think the world of totally digital is still some way off.

And while things like good vinyl replay still beats all digital disc
formats,
there will always be a following for analog.

I will be dead in 25 years, or deaf by then, so I won't give a hoot what
the human race does after that.

Patrick Turner.