[1000mp] Speaker Choice - Not HiFi
J. Mc Laughlin
[email protected]
Sun, 31 Mar 2002 12:26:20 -0500
Dear Bill and others:
Thanks for the lessons. I see a pattern in most of the observations
and I continue to look for more patterns.
I managed to forget/overlook that some radio amateurs with serious
radios (FT1000 series) are not ### radio amateurs. (Substitute whatever
modifier you think appropriate for ###.) I am a ### radio amateur and,
in a quest to glean as much as is possible from the signals, use
headphones.
Several of you have given me perspective on how other than ### radio
amateurs use their radios. That awareness will help me to understand
future messages. Thanks to all.
Slightly off topic, a radio amateur colleague of mine, who was once
my student, performed a set of interesting tests on "HiFi" audio
amplifiers. He measured the various types of distortion with the
internal power supply(s) and then repeated the same measurements with an
external, stiff power supply. Big difference in favor of the stiff PS.
Apparently, the industry standard allows manufactures to spec. their
amplifiers as they perform with an external PS!
Thanks again for the reminder that we are not all ### radio
amateurs. 73 Mac N8TT
J. Mc Laughlin - Michigan USA
Home: [email protected]
Office: [email protected]
----- Original Message -----
From: "WD8ARZ" <[email protected]>
To: <[email protected]>
Sent: Sunday, March 31, 2002 12:24 AM
Subject: Re: [1000mp] Speaker Choice - Not HiFi
> Thanks for bring up your point Mac, had the same thoughts in my mind.
I tend
> to use communications grade stereo headphones a lot my self. I the
shack I
> will use a pair of HS-1661 Communications grade speakers. When roaming
> around the house and outside I use wireless head phones, and wireless
> speakers depending on circumstances .... and never do I use music and
hifi
> speakers for my communications receivers.
>
> A hifi speaker being fed by a narrow bandwidth audio amp output
doesn't make
> sense of course. Not only is the frequency range of the speaker not
> supported by the receiver audio, but your also doing a dis-service to
the
> signal to noise ratio for the intelligibility portion of the voice
audio
> that you really want ..... plus the hifi speakers are giving more
output to
> the low end bass where voice intelligibility is not at .... and the
static
> crashes are at .... the end result is a much harder to understand
human
> voice, especially during summer static.
>
> I use Heathkit HS-1661speakers that are tailored for the intelligible
range
> of human speech .... ends up being easier to understand the output,
and with
> a better more fatigue free listening to boot. That's what
communications
> grade speakers are meant to do. Speakers meant for HiFi Stereo are not
> communications grade speakers.
>
> Some may have forgotten that transmitted audio puts most of its power
in the
> low frequencies, but we need the higher frequencies to make out the
spoken
> word mixed in with noise.... with less power in the high frequencies,
range
> is reduced.
> That's why the dxer higher frequency punch is used and the lows
trimmed
> ...... now the power that was being put into the low frequencies that
don't
> contribute so much to understandability, is going to the higher range
where
> it is needed for better readability.
>
> Under strong signal conditions, AM signals on large wider frequency
range
> speakers can seem to be nicer and thus the way to always go for
listening
> under all conditions, and that is simply not true of course. Some
using the
> legally questionable wide 6khz sideband, and pushing low frequency
audio
> trying to emulate AM audio quality, are actually a step backwards for
what
> Ssb communications is all about... ...which is improving range and
> intelligibility using less power than the same AM signal (AM as in
double
> sideband with carrier, of course single side band is also AM) AND less
band
> space.
>
> Reducing the noise and keeping the audio frequency range to the
> intelligibility range, also improves the spatial processing of our
brain
> processor when using dual receiver and diversity mode reception
techniques.
>
> 73 from Bill - WD8ARZ
> [email protected]
>
> ----- Original Message -----
> From: "J. Mc Laughlin" <[email protected]>
> To: <[email protected]>
> Sent: Saturday, March 30, 2002 23:08
> Subject: Re: [1000mp] Speaker Choice
>
>
> > I have been puzzled by this thread. I can not understand why one
would
> > use a speaker at all with the radio. Some assumption is not being
> > stated.
> >
> > A pair of headphones with one receiver connected to one side, and
the
> > other receiver connected to the other side, seems to be the natural
way
> > for a human to process aural signals. I understand that some are
using
> > two speakers.
> >
> > Signal to noise ratio is the game. How does a loudspeaker help SNR?
> > One would expect extraneous sounds to degrade SNR.
> >
> > Presumably other persons are about. One would expect the sound from
> > loudspeakers to tend to be disturbing to others.
> >
> > Teach me what benefit accrues from the use of loudspeakers. 73
> > Mac N8TT
> >
> > J. Mc Laughlin - Michigan USA
> > Home: [email protected]
> > Office: [email protected]
>