Re: "Listeners don't want DAB"

On 31/08/2009 02:46, DAB sounds worse than FM wrote:
"Peter Watson"<peter@xxxxxxxxxxx> wrote in message
news:7g060eF2nl1oaU1@xxxxxxxxxxxxxxxxxx
On 30/08/2009 16:48, steve41@xxxxxxxxxxxxxx wrote:
On Aug 30, 3:24 pm, "jamie powell"<jamie_...@xxxxxxxxxx> wrote:
"DAB sounds worse than FM"<dab...@xxxxxxxxxx> wrote in

Shame the diagram you keep posting is wrong then isn't it? :)


It looks about right to me with regards to the stuff below 53 kHz,
which covers all the signals that have been discussed in this thread.

If you've found something wrong with the figure above 53 kHz, I'm
afraid I pity you for even mentioning it on here considering that that
stuff hasn't been mentioned at all, and it would simply highlight what
an incredibly pedantic fool you are.

Look at the diagram again Steve - The error is probably a typo but it's there nevertheless. Always check the accuracy of someone else's work before you quote it :)

Pedantic - "Pots and kettles" I think!




Er, if you recall, the discussion of this began when I had
reviewed a
Roberts DAB/FM portable radio which did have hiss present on the
mono
speaker because it had incorrectly been set to stereo mode by
default.
I contacted Roberts saying that was a fault with this radio,
precisely
because "stereo hiss" should not be present on a mono speaker.

...and the *reason* you concluded that the hiss shouldn't be there
was
because the radio was set to Stereo but *if* Mono was derived for
the
speaker either by combining L&R *or* using the Mono output of the FM
stage then the mode *shouldn't* have made any difference!

The conclusion therefore is that the receiver was faulty (you got
that
bit right) because the derivation of Mono didn't work correctly,
*not
because the receiver was set to Stereo*...


Oh, have you got the circuit diagram for the Roberts radio I reviewed
as well then? Out of interest, how did you manage to figure out which
Roberts radio I reviewed when I haven't mentioned it? Do you have
supernatural powers there, Petey? And out of interest, how do you know
that there wasn't a software bug in the software-defined radio FM
receiver implementation, when, IIRC, theory shows that it's impossible
to prove that no bugs exist in a piece of software?

Your wriggling again :) Circuit diagram and precise model not required to challenge your conclusion... *If* there was a 'bug' that meant there was a difference in noise performance between Stereo and Mono, then what I said still stands - Mono was derived incorrectly.

.

Relevant Pages

  • Re: "Listeners dont want DAB"
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  • Re: "Listeners dont want DAB"
    ... If you've found something wrong with the figure above 53 kHz, ... It's the same as the DAB+ inventor vs the clock radio mender thing I ... because "stereo hiss" should not be present on a mono speaker. ...
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