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Side Tone

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charles-70

Side Tone

I built K2 Nr 413 and made lots of CW contacts, the built in Mojo was great.
I stopped using it because the crystal oscillator in the side tone was
not a pure sine wave and it became offensive to my ear. I only use CW.

I have been informed by a K2 op that the more recent versions have a
better side tone. If this is so then I may consider building the K2/100.
Could some one please help me with this decision?

Charles
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David Pratt

Re: Side Tone

In message <[hidden email]>, Charles
<[hidden email]> writes
>I built K2 Nr 413 and made lots of CW contacts, the built in Mojo was great.
>I stopped using it because the crystal oscillator in the side tone was
>not a pure sine wave and it became offensive to my ear. I only use CW.
>
>I have been informed by a K2 op that the more recent versions have a
>better side tone.

That is correct, Charles. There was a mod by WJ4P, called the "Sinewave
Sidetone Mod" which involved fitting a 47K resistor in series with C24
(0.0027uF) on the control board and soldering a 39mH choke across pins 7
& 10 of RP5. Ensure that C33 is a 2.2uF. If not, replace it.

There is a document around about the mod somewhere and I am trying to
locate it. If I find it I will e-mail it to you.

The later Revision B K2 has a sinewave mod incorporated.

73 de David G4DMP

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Don Wilhelm-3

RE: Side Tone

In reply to this post by charles-70

Charles,

The parts for the sidetone waveshape mod are included with the KATOBKT from
Elecraft. The values differ slightly from those in the original sidetone
waveshape mod, but both work - still not a pure sinewave, but much closer
than before.

You should consider doing the complete A to B upgrade including all the
optional parts along with making a change to the new crystal set - you will
not be sorry after you hear the difference. Download the A to B instruction
manual and look at the changes listed on the first page. And if you are
considering the addition of a KPA100, I highly recommend that you also add
the keying waveshape change. The Extremely Strong Signal Handling change
came after the A to B kit too, but no kit for it - just takes 2 1N4148
diodes to add it. For about $70US you can end up with a K2 that is equal to
the current production K2s - there IS a difference.

73,
Don W3FPR

> -----Original Message-----
>
> I built K2 Nr 413 and made lots of CW contacts, the built in Mojo
> was great.
> I stopped using it because the crystal oscillator in the side tone was
> not a pure sine wave and it became offensive to my ear. I only use CW.
>
> I have been informed by a K2 op that the more recent versions have a
> better side tone. If this is so then I may consider building the K2/100.
> Could some one please help me with this decision?
>
> Charles
>

Don Nesbitt

Re: Side Tone

In reply to this post by charles-70

Seems my ISP is blocked from the list - trying again 73 --Don N4HH
----- Original Message -----
From: "Don Nesbitt" <[hidden email]>
To: "Charles" <[hidden email]>; <[hidden email]>
Sent: Wednesday, January 04, 2006 7:24 AM
Subject: Re: [Elecraft] Side Tone

> Check out the info on Sverre's page:
> http://www.qslnet.de/member/la3za/K2/mod.html lots of good stuff here.
>
> Look under item #2 for a Sidetone mod of just go to :
> http://www.elecraft.com/Apps/sinewave_sidetone_mod.htm
>
> 73 es hv fun -- Don N4HH
>
> ----- Original Message -----
> From: "Charles" <[hidden email]>
> To: <[hidden email]>
> Sent: Wednesday, January 04, 2006 5:15 AM
> Subject: [Elecraft] Side Tone
>
>
>>I built K2 Nr 413 and made lots of CW contacts, the built in Mojo was
>>great.
>> I stopped using it because the crystal oscillator in the side tone was
>> not a pure sine wave and it became offensive to my ear. I only use CW.
>>
>> I have been informed by a K2 op that the more recent versions have a
>> better side tone. If this is so then I may consider building the K2/100.
>> Could some one please help me with this decision?
>>
>> Charles
>> _______________________________________________
>> Elecraft mailing list
>> Post to: [hidden email]
>> You must be a subscriber to post to the list.
>> Subscriber Info (Addr. Change, sub, unsub etc.):
>> http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/subscribers.htm
>> Elecraft web page: http://www.elecraft.com
>>
>>
>> --
>> No virus found in this incoming message.
>> Checked by AVG Free Edition.
>> Version: 7.1.371 / Virus Database: 267.14.11/219 - Release Date: 1/2/2006
>>
>>
>

EricJ-2

Side Tone (Choosing the right "music")

In reply to this post by charles-70

With so many musicians on here, including the K1/K2 designer, maybe someone
would comment on why sidetones are the frequency they are. Actually, I have
been thinking more about how people choose the OFFSET they prefer more than
the sidetone, but it's the same idea.

It's interesting that you should say the sidetone was offensive because it
was not a pure sine wave. It is my understanding (not being a musician
myself), that humans prefer tones with harmonic content. Pure sine waves
sound simple and harsh to the ear. Maybe we would find that even with a
sidetone, there is some preferred harmonic content that makes it richer and
more pleasing to listen to. The same goes for the offset frequency. I, and
others, have commented on how much better the K1 sounds to us compared to
even the K2. I don't know what quality the K1 has that makes us think that
way, but there is something going on there that makes me choose the K1 for
ragchewing. Something makes it less fatiguing or otherwise more pleasant for
me, and it is independent of the speaker as I have traded external speakers
back and forth bewteen the K1 and the K2.

While thinking about it, and again, not being a musician, I began wondering
why piano keys are tuned to the very specific, but seemingly odd frequencies
they are. The lowest note on a piano is 28.5 Hz. Who decided something like
that? Esp. way back 200+ years ago. All of the white keys are harmonically
related to that bizarre 28 and 1/2 hz, now I know the reason for that, but
why did they choose that particular frequency? I don't know the answer to
that, but maybe it evolved over decades or even centuries of humans
responding well to certain notes and not to others. (I should have done some
basic research first, I guess). I doubt they were chosen at random and
probably really do seem to be frequencies humans prefer.

If that is so, why don't we pick offsets that correspond to musical notes?
Why do most of us pick some arbitrary offset rounded to the nearest 50 or
100. When we talk about offsets here, we are nearly always talking about 500
or 600 or 700 or the screeching 1000 hz or higher offset that comes fixed in
a lot of earlier rigs. Maybe the offset on the K1/K2 menus should be
calibrated in musical notes instead of arbitrary decade increments.

Eric
KE6US
www.ke6us.com

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Charles
Sent: Wednesday, January 04, 2006 2:16 AM
To: [hidden email]
Subject: [Elecraft] Side Tone

I built K2 Nr 413 and made lots of CW contacts, the built in Mojo was great.
I stopped using it because the crystal oscillator in the side tone was not a
pure sine wave and it became offensive to my ear. I only use CW.

I have been informed by a K2 op that the more recent versions have a better
side tone. If this is so then I may consider building the K2/100.
Could some one please help me with this decision?

Charles
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Vic K2VCO

Re: Side Tone (Choosing the right "music")

EricJ wrote:

> It's interesting that you should say the sidetone was offensive because it
> was not a pure sine wave. It is my understanding (not being a musician
> myself), that humans prefer tones with harmonic content. Pure sine waves
> sound simple and harsh to the ear.

Not harsh, but boring. But anyway, the reason a pure sine wave is
desirable is that it makes matching pitch with a received signal easier.

Back in the day I always used neon-bulb sawtooth shaped sidetones.
Digitally generated square waves are ugly.
--
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco
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Jason Artz

Re: Side Tone (Choosing the right "music") Mostly OT

In reply to this post by EricJ-2

Hi Eric,

Interesting thoughts. I am a professional musician
and owner of a K1. I could write pages (and have,
back in school) on how and why pianos are tuned the
way they are -- they are giant mess, pitch-wise, for
many many reasons, but through lots of compramises you
end up with something that sounds good. I will say
that when I originally built and set up my K1, I chose
a sidetone/offset frequency of 440Hz because that is
the tuning note (A) at standard US "concert pitch."
The K1 wasn't dead on, though, and adjustments are by
10 whole Hz, so it bothered me a bit and I chose 600Hz
because it sounded good on my headphones and seemed a
popular choice. :)

I can't comment on the difference in received CW tone
on a K1 versus K2 because I've never heard a K2. I
find the sidetone on the K1 to be pretty rich,
harmonically, but not bad. I'd prefer it a little
less so, though, or with a different distribution of
harmonics present at different levels (sounds like a
good new add-on - essentially a synthesizer/eq for
your K1's sidetone - how about it, guys?! ;) ). What
makes one instrument sound different from another is
partially the harmonic content and the amplitudes of
each harmonic relative to the others. Another aspect
is the start and stop of the tone (waveform shaping?).
I am sure someone could design a sidetone that would
sound like an instrument or some other more "pleasing"
tone. Then they could patent it like Harley Davidson
did with their sound.

As far as why we have the frequencies we have on the
piano (or any other western instrument), it's
generally based on the A above middle C being 440Hz.
The rest of the notes are based on that,
mathematically. It isn't always 440Hz, though - it's
a bit higher in most of Europe (442-444Hz) and has
historically been all over the place - as low as maybe
380 and as high as 490. There are lots of theories as
to how 440Hz became popular - could go on about that
but I won't. :) Suffice it to say that instruments
made of certain materials, at certain sizes, will
resonate (and "sound") better at certain frequencies.
I think that, over time, the evolution of instruments
and pitches settled in a range that works best with
the material and acoustic limitations that we face.
(It's still not static, though)

Why the particular tones within the octave? It's a
western thing - they've got way more notes in
traditional Indian music and fewer in China.

73,
Jason
ak7v

--- EricJ <[hidden email]> wrote:

> With so many musicians on here, including the K1/K2
> designer, maybe someone
> would comment on why sidetones are the frequency
> they are. Actually, I have
> been thinking more about how people choose the
> OFFSET they prefer more than
> the sidetone, but it's the same idea.
>
> It's interesting that you should say the sidetone
> was offensive because it
> was not a pure sine wave. It is my understanding
> (not being a musician
> myself), that humans prefer tones with harmonic
> content. Pure sine waves
> sound simple and harsh to the ear. Maybe we would
> find that even with a
> sidetone, there is some preferred harmonic content
> that makes it richer and
> more pleasing to listen to. The same goes for the
> offset frequency. I, and
> others, have commented on how much better the K1
> sounds to us compared to
> even the K2. I don't know what quality the K1 has
> that makes us think that
> way, but there is something going on there that
> makes me choose the K1 for
> ragchewing. Something makes it less fatiguing or
> otherwise more pleasant for
> me, and it is independent of the speaker as I have
> traded external speakers
> back and forth bewteen the K1 and the K2.
>
> While thinking about it, and again, not being a
> musician, I began wondering
> why piano keys are tuned to the very specific, but
> seemingly odd frequencies
> they are. The lowest note on a piano is 28.5 Hz. Who
> decided something like
> that? Esp. way back 200+ years ago. All of the white
> keys are harmonically
> related to that bizarre 28 and 1/2 hz, now I know
> the reason for that, but
> why did they choose that particular frequency? I
> don't know the answer to
> that, but maybe it evolved over decades or even
> centuries of humans
> responding well to certain notes and not to others.
> (I should have done some
> basic research first, I guess). I doubt they were
> chosen at random and
> probably really do seem to be frequencies humans
> prefer.
>
> If that is so, why don't we pick offsets that
> correspond to musical notes?
> Why do most of us pick some arbitrary offset rounded
> to the nearest 50 or
> 100. When we talk about offsets here, we are nearly
> always talking about 500
> or 600 or 700 or the screeching 1000 hz or higher
> offset that comes fixed in
> a lot of earlier rigs. Maybe the offset on the K1/K2
> menus should be
> calibrated in musical notes instead of arbitrary
> decade increments.
>
> Eric
> KE6US
> www.ke6us.com
>
>
>
>
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf
> Of Charles
> Sent: Wednesday, January 04, 2006 2:16 AM
> To: [hidden email]
> Subject: [Elecraft] Side Tone
>
> I built K2 Nr 413 and made lots of CW contacts, the
> built in Mojo was great.
> I stopped using it because the crystal oscillator in
> the side tone was not a
> pure sine wave and it became offensive to my ear. I
> only use CW.
>
> I have been informed by a K2 op that the more recent
> versions have a better
> side tone. If this is so then I may consider
> building the K2/100.
> Could some one please help me with this decision?
>
> Charles
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
>
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
>
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
>

EricJ-2

RE: Side Tone (Choosing the right "music") Mostly OT

So maybe Chinese or Indian export models should include more sidetone
options. Hi.

My offset is also around 600 hz. In a blind test, it sort of settled there,
but I remember being undecided because the steps were too far apart. Like
some other tone close by would actually have been better for me.

Anyway, it is something that I have been kicking around with no background
to make sense of it. Your note helps give me some direction for further
research. A friend of mine has a PhD in Dance specializing in Balinese dance
and she has mentioned the expanded scale of Eastern music as well.

There is always a way to make a BFD out of the simplest thing...even a
sidetone.

Eric
KE6US
www.ke6us.com

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Jason Artz
Sent: Wednesday, January 04, 2006 10:29 AM
To: [hidden email]
Subject: Re: [Elecraft] Side Tone (Choosing the right "music") Mostly OT

Hi Eric,

Interesting thoughts. I am a professional musician and owner of a K1. I
could write pages (and have, back in school) on how and why pianos are tuned
the way they are -- they are giant mess, pitch-wise, for many many reasons,
but through lots of compramises you end up with something that sounds good.
I will say that when I originally built and set up my K1, I chose a
sidetone/offset frequency of 440Hz because that is the tuning note (A) at
standard US "concert pitch."
The K1 wasn't dead on, though, and adjustments are by 10 whole Hz, so it
bothered me a bit and I chose 600Hz because it sounded good on my headphones
and seemed a popular choice. :)

I can't comment on the difference in received CW tone on a K1 versus K2
because I've never heard a K2. I find the sidetone on the K1 to be pretty
rich, harmonically, but not bad. I'd prefer it a little less so, though, or
with a different distribution of harmonics present at different levels
(sounds like a good new add-on - essentially a synthesizer/eq for your K1's
sidetone - how about it, guys?! ;) ). What makes one instrument sound
different from another is partially the harmonic content and the amplitudes
of each harmonic relative to the others. Another aspect is the start and
stop of the tone (waveform shaping?).
I am sure someone could design a sidetone that would sound like an
instrument or some other more "pleasing"
tone. Then they could patent it like Harley Davidson did with their sound.

As far as why we have the frequencies we have on the piano (or any other
western instrument), it's generally based on the A above middle C being
440Hz.
The rest of the notes are based on that, mathematically. It isn't always
440Hz, though - it's a bit higher in most of Europe (442-444Hz) and has
historically been all over the place - as low as maybe 380 and as high as
490. There are lots of theories as to how 440Hz became popular - could go
on about that but I won't. :) Suffice it to say that instruments made of
certain materials, at certain sizes, will resonate (and "sound") better at
certain frequencies.
I think that, over time, the evolution of instruments and pitches settled in
a range that works best with the material and acoustic limitations that we
face.
(It's still not static, though)

Why the particular tones within the octave? It's a western thing - they've
got way more notes in traditional Indian music and fewer in China.

73,
Jason
ak7v

--- EricJ <[hidden email]> wrote:

> With so many musicians on here, including the K1/K2 designer, maybe
> someone would comment on why sidetones are the frequency they are.
> Actually, I have been thinking more about how people choose the OFFSET
> they prefer more than the sidetone, but it's the same idea.
>
> It's interesting that you should say the sidetone was offensive
> because it was not a pure sine wave. It is my understanding (not being
> a musician myself), that humans prefer tones with harmonic content.
> Pure sine waves sound simple and harsh to the ear. Maybe we would find
> that even with a sidetone, there is some preferred harmonic content
> that makes it richer and more pleasing to listen to. The same goes for
> the offset frequency. I, and others, have commented on how much better
> the K1 sounds to us compared to even the K2. I don't know what quality
> the K1 has that makes us think that way, but there is something going
> on there that makes me choose the K1 for ragchewing. Something makes
> it less fatiguing or otherwise more pleasant for me, and it is
> independent of the speaker as I have traded external speakers back and
> forth bewteen the K1 and the K2.
>
> While thinking about it, and again, not being a musician, I began
> wondering why piano keys are tuned to the very specific, but seemingly
> odd frequencies they are. The lowest note on a piano is 28.5 Hz. Who
> decided something like that? Esp. way back 200+ years ago. All of the
> white keys are harmonically related to that bizarre 28 and 1/2 hz, now
> I know the reason for that, but why did they choose that particular
> frequency? I don't know the answer to that, but maybe it evolved over
> decades or even centuries of humans responding well to certain notes
> and not to others.
> (I should have done some
> basic research first, I guess). I doubt they were chosen at random and
> probably really do seem to be frequencies humans prefer.
>
> If that is so, why don't we pick offsets that correspond to musical
> notes?
> Why do most of us pick some arbitrary offset rounded to the nearest 50
> or 100. When we talk about offsets here, we are nearly always talking
> about 500 or 600 or 700 or the screeching 1000 hz or higher offset
> that comes fixed in a lot of earlier rigs. Maybe the offset on the
> K1/K2 menus should be calibrated in musical notes instead of arbitrary
> decade increments.
>
> Eric
> KE6US
> www.ke6us.com
>
>
>
>
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of Charles
> Sent: Wednesday, January 04, 2006 2:16 AM
> To: [hidden email]
> Subject: [Elecraft] Side Tone
>
> I built K2 Nr 413 and made lots of CW contacts, the built in Mojo was
> great.
> I stopped using it because the crystal oscillator in the side tone was
> not a pure sine wave and it became offensive to my ear. I only use CW.
>
> I have been informed by a K2 op that the more recent versions have a
> better side tone. If this is so then I may consider building the
> K2/100.
> Could some one please help me with this decision?
>
> Charles
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
>
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
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>
> Help: http://mailman.qth.net/subscribers.htm
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>

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Nick Waterman

Re: Side Tone (Choosing the right "music")

In reply to this post by Vic K2VCO

Vic K2VCO wrote:
> Not harsh, but boring. But anyway, the reason a pure sine wave is
> desirable is that it makes matching pitch with a received signal easier.

Well, and bandwidth. A pure sine wave uses, errr, almost zero
bandwidth*, whereas one with harmonics needs somewhere to put those. A
500Hz sine wave at 7100kHz is really a sine at 7100.5, whereas a 500Hz
sine wave with harmonics at 1000 and 1500 kHz is now using 7100.5, 7101,
7101.5...

... or am I preaching to the choir here?

* Yeah, yeah, ok, not quite true as soon as you start modulating it with
keying envelopes.

--
"Nosey" Nick Waterman, G7RZQ, k2 #5209.
#include <stddisclaimer> [hidden email]
It is ten o'clock; do you know where your processes are?
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EricJ-2

RE: Side Tone (Choosing the right "music")

Well, sidetone and the tone generated from offset is not
transmitted...except into your head via the ear canal which has excess audio
bandwidth when listening to CW.

Eric
KE6US
www.ke6us.com

-----Original Message-----
From: Nick Waterman [mailto:[hidden email]]
Sent: Wednesday, January 04, 2006 3:10 PM
To: Vic K2VCO
Cc: EricJ; [hidden email]
Subject: Re: [Elecraft] Side Tone (Choosing the right "music")

Vic K2VCO wrote:
> Not harsh, but boring. But anyway, the reason a pure sine wave is
> desirable is that it makes matching pitch with a received signal easier.

Well, and bandwidth. A pure sine wave uses, errr, almost zero bandwidth*,
whereas one with harmonics needs somewhere to put those. A 500Hz sine wave
at 7100kHz is really a sine at 7100.5, whereas a 500Hz sine wave with
harmonics at 1000 and 1500 kHz is now using 7100.5, 7101, 7101.5...

.. or am I preaching to the choir here?

* Yeah, yeah, ok, not quite true as soon as you start modulating it with
keying envelopes.

--
"Nosey" Nick Waterman, G7RZQ, k2 #5209.
#include <stddisclaimer> [hidden email]
It is ten o'clock; do you know where your processes are?
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