[Elecraft] K3 Audio (WAS K3 eHam review after 2+ years)

[Alexander Ponomarenko]

Guy,

it is possible make the K3 audio more audiophile.
Good sound are always better, for contesting or for listening pleasure. :-)
If we has less audio distortions we can to hear the pule-up's more 
comfortable.
Why K3 named CW-rigs? Because CW needed narrow passband, and as result
less noise and distortions in passband. For SSB or CW-wide-passband 
effect ''harshness''
more is brightly expressed, if we have several stations inside.
Here is same mods from my friend and K3-owner RA3BA.
First mod included replacement two caps, and added one cap in AF-amp.
This mod allows to get much more audiophile sound.
Second mod are for ""IF buffer AMP"" capasitors.
This mod give more clear sound, bacause this mod allows to improve of 
the K3-noise.

Same weeks ago we talk about this mods in "K3-Headphone"-thread:

"I has tried replacing the 10uF caps with 100uF in AF-amp, also in
data-sheet for LM4811MM we see for the pin 10 have to add for 1uF cap.
These caps - near Front Panel Phone Out. C9=C13=100uF 10V
also add 1uF: "+" to pin 10 U2; "-" to ground. 
The result is excellent with my ProSet.
Sound clean and deep. Signals became more raised, proturberant, appeared
"body of the sound", clearly differ the most small details in signals. 
Such sensation, that earlier the signals got through blanket,
but now here is they, straight before my eyes, and they proturberant and
volumetric.
As my ears as SpectroLab also "sees the difference". You can see my
plots "before" and "after" same mods."

before mods:   http://forum.cqham.ru/download.php?id=43281
after mods:  http://forum.cqham.ru/download.php?id=43282

before s9 level:  http://forum.cqham.ru/download.php?id=43279
after s9 level:  http://forum.cqham.ru/download.php?id=43280

"IF buffer amplifier also have to be modified. Using only 
electrolytic caps C84 and C92 not is enough, they must be bypass
by ceramic caps."
Photo: http://forum.cqham.ru/files/thumbs/t_img_0009_928.jpg

Try these mods, and yours K3's will have excellent sound.
Good luck!

73! Alex

Guy Olinger K2AV:
> The DAC artifacts I see clearly on spectrum analysis down 60 would have been
> 20 db over my hearing floor, and annoying, as I had the typical reaction to
> someone raking their fingernails down a chalkboard.
>
> However, I still DO hear any intermod in 3-6 kHz over top of a 3 kHz
> bandwidth signal, and it DOES make the audio seem harsh if there is anything
> there.
>
> Does harshness make any difference in a contest?  Not that I can tell.  40m
> has all kinds of annoying crud that comes in.  Less crud if it's a K3.  40m
> is an annoying band. But I didn't buy the K3 for audiophile audio.
>
> Given that, I would have to say that the RX is an unqualified success in its
> intended design.  But if Elecraft was to offer an audiophile upgrade to the
> K3 audio, I would put it in -- not for contesting, but just for listening
> pleasure.
>
> It would be really neat if somehow Elecraft could produce audiophile audio
> in the K3, but for the price spent and the central premise of the design, an
> admitted harshness is just nit-picking.  I'll take a K3 board that Elecraft
> intends to be audiophile outcome, and complain about that if it misses, but
> I bought my current K3 for the contest results.
>
> 73, Guy.
> K2AV
>