I'm only going to say that to dismiss something solely because "it's always
been that way" is a terribly closed minded way to look at something. I'm fully
aware of why ~200-3.4k was chosen (as I mentioned before) -- it was the best
trade-off between speech intelligibility and network resources. This is not in
dispute!! I also fully realize that when you use a narrow BW, the noise floor
drops proportionately. What *I'm* saying is that when you give the distant end
a little more than 400-2.4k, say up to 3, 3.3 or 3.4k, even when they are using
a narrow receive BW, it's logical to conclude that they have more there to hear
through the mess. In my (admittedly non-scientific) experimentation, that's
what I have found. It works very well for me, and I think there's something to
it. To morph a phrase from Rich, "Mo' narrower ain't necessarily mo' better".
I would also be the last one to tell you that "pumped up bass and extended
highs" are better in high QRM/QRN band
conditions. This is separate than wanting to be able to enjoy full-range QSOs
in non-crowded bands, and the mechanics of how extended BW improves
intelligibility *in good S/N conditions* (which is simple common sense to me).
Let's try to keep the two separated. Again, there is a time & place for each.
And to claim Bell's research as a reason to use 400-2.4k is off-base since the
typical telephone system channel is ~200-3.4k or 3.2k total BW based on the
same research. Which, oddly enough isn't too far from what I found works well
for me in high QRM/QRN conditions. Go figure.
Anyway, I'm off to get that analyzer to capture some data on wider speech BW on
my rig's RF performance.
73,
Joe, N3JI
----- Original Message ----
From: Tom W8JI <w8ji@w8ji.com>
To: Gudguyham@aol.com; kdutson@sbcglobal.net; n3ji@yahoo.com; w4tv@subich.com;
amps@contesting.com
Sent: Tuesday, July 4, 2006 8:52:19 AM
Subject: Re: [Amps] Maximum RF output in practical application: 4-250A
> All I can say is that when there is significant noise &
> QRM, that extra
> couple hundred Hz of articulation seems to make a
> difference.
>
> Has anyone else experimented with that?
> Joe, N3JI
I do all the time, and when there is significant noise and
QRM **LESS** bandwidth improves copy provided that bandwidth
is properly centered.
If you listen to widefi AM guys, those with the deepest bass
and highest highs are the very worse to copy when signals
are tough. SSB is no different at all.
This has been known a long long time Joe. Not only is this
thread out of place on an amplifier forum, it has reached an
impasse. People who want WideFi will go through any extreme,
including the use of a white paper created by a company who
sells (no surprise) wide-fi audio systems to replace regular
telephones. Those who don't swallow all the bean soup will
stick with the same arguments Art Collins and the rest went
by, and that any DX'er already knows.
It really is pointless to continue this. It's like trying
get a guy with a Hummer to admit it is a waste of resources
or a guy who drive a sports car to enjoy a land-yacht. No
matter what the technical facts or situation, people will
find any reason to justify what they think is right. When I
look at all the banter on Internet or listen to
conversations, it's clear very few audio affectionos seems
to grasp the basics of communications systems. W9AC is a
rare exception who both understands it and has common sense.
People would be well-advised to listen to Paul if they don't
trust respected commercial communication sources.
If the band is not crowded and wide-fi guys are away from
weak signal areas, they can have all the bandwidth they
want. When the band is busy, even if they are there first,
they should be smart enough and considerate enough to
throttle it back to the minimum necessary. The AM guys have
enough sense to confine activity to areas of the band away
from potential problems, and the AM guys also have enough
sense to get off the band when it is crowded.
The only thing I object to is all the nonsense about wider
bandwidth makes better weak signal or is better at QRM
cutting.
I hope this thread dies soon. It has NOTHING to do with
4-250A's. It belongs on a bandwidth forum.
73 Tom
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