[Elecraft] KX1 headphones

[Wes Stewart]

I concur 100% with Brett (for a change).  Filtering should be done electronically where it can be controlled, not mechanically where all it does is add distortion.

It was a revelation when I was first working EME in the early eighties and was still using some military "communications" headphones and I changed over to some Koss "hi-fi" phones and an in-line 200 Hz wide LC filter.  There were signals buried in that mush that was all I was hearing with the "communications" phones.

Later I bought into the brand "H" hype and got a headset at my local ham emporium.  After about five minutes of listening, I took them back. They were simply awful!  I don't think much of the microphones either, even though they are wildly popular.

It's hard to beat a nice passive LC brute force filter.  They can clean up a multitude of sins that we are presented with by the afterthought audio stages in modern transceivers.

Wes  N7WS


--- On Sat, 8/22/09, Brett Howard <brett at livecomputers.com> wrote:

> From: Brett Howard <brett at livecomputers.com>
> Subject: Re: [Elecraft] KX1 headphones
> To: 
> Cc: elecraft at mailman.qth.net
> Date: Saturday, August 22, 2009, 7:05 PM
> The filtering should be done before
> the audio gets to the headphones.
> A low end pair of headphones only acts to cover up flaws in
> receiver
> design.  A good broadband pair of uncolored headphones
> should be good
> for reproducing audio as it was intended to be done
> so.  While some
> audio reproduction systems are designed to be colored they
> are by
> nature much less versatile and have narrower usage cases.
> 
> ~BTH
> 
> 
> On Sat, Aug 22, 2009 at 5:53 PM, Mike Morrow<kk5f at earthlink.net>
> wrote:
> >>I would not have spent the money on my Etymotics
> just for listening to
> >>CW, but since they are great for listening to music
> with great fidelity
> >>while traveling on planes, which is something I do
> a lot of, I look at it
> >>as a bonus that they will be nice to use in
> conjunction with my KX-1
> >>once I build it.
> >
> > The absolute worst thing one can have in a speaker or
> headphones for
> > communications use is "high fidelity" and broad
> frequency response!!!
> >
> > Communications-quality audio devices are deliberately
> *designed* for limited
> > frequency response (typically about 300 to 3000 Hz).
>  Anything of higher
> > "fidelity" is adverse to quality in a communications
> device.
> >
> > One might as well eliminate receiver IF and front-end
> filtering if high
> > fidelity is the goal.  But, of course, high fidelity
> is not the goal.   Just as
> > receiver IFs with limited bandpass are desirable,
> especially for CW
> > communications, so are headphones with narrow
> frequency response.
> > Narrow frequency response helps eliminate undesired
> signals as surely
> > as that IF filter.  And since the front-end and IF
> filtering in the KX-1 is
> > limited, hi-fi entertainment headsets are the last
> thing one needs.
> >
> > QRP rig designers usually provide a headphone jack
> that accepts the common
> > entertainment-quality headphones with stereo
> connections.  That seems to
> > encourage the use of these unsatisfactory
> entertainment audio devices,
> > whether they be $5 Walmart specials or much worse,
> those wildly overpriced
> > "specialty" hi-fi headsets.
> >
> > The best earbuds for communications use that I've ever
> found are Kenwood
> > HS-7 mono earbuds, with the essential limited
> frequency response.
> > Unfortunately they haven't been available for more
> than a decade.
> >
> > If you have headsets that are spec'd for entertainment
> audio purposes, that
> > should immediately be a warning that they are far from
> optimal for communications
> > use unless nothing else is available.
> >
> > Mike / KK5F
> >