[Elecraft] K3: vs a Collins S-line RX

[Erik Basilier]

Since nobody has answered yet, I will give it a shot, although it is
entirely subjective and not even based on recent observations. I am
commenting only about receive audio, and only ssb. I have a KWM-2, and had
the same question on my mind years ago. Here is what I recall. When I got
the KWM-2 I had an FT-1000D, and I noticed that ssb sounded much better in
the Collins, at the same 2.1 KHz filter width. I attributed this to two
separate effects: Class A audio power amp in the Collins vs push-pull
semiconductor pa in the Yaesu, and mechanical filter in the Collins vs. xtal
filters in the Yaesu. I think the mechanical filters may have less phase
distortion and less group delay variations than the xtal units; at least
that was my guess at the time. Then I sold the Yaesu and bought an early K3
#18xx. The K3 was much superior to both the other radios in almost every
respect, but the ssb receive audio was the rare exception. It was inferior
to the Collins. I felt it was also worse than the Yaesu, although both rigs
used xtal filters (not the whole K3 story; spare me the flames) and solid
state push pull audio pa's. Later I got Elecraft's hardware upgrades for the
rx audio, and they made a big difference. I now feel the K3 is at least as
good as the Yaesu. Still I don't feel it is as good as the Collins. Later
still I got a KX3. It sounds incredibly good in a certain sense that I
attribute to the selectivity being affected by on no xtal or mechanical
filters. OTOH I feel that its audio pa suffers from not being class A. So
the KX3 and the Collins have opposite strengths and weaknesses. Overall, the
KX3 wins over the Collins. So, with these radios to choose from, which one
do I turn on when I have time to get on the air? The K3 wins overall, and
not just because more tx power is available. It is just a little bit more
comfortable to operate. BTW I haven't experimented with running the K3 with
a roofing filter much wider than the DSP bandwidth; perhaps that would
improve the receive audio noticeably? Warning: The above are my subjective
observations and not supported by any measurements. I post this with much
hesitation. Probably some Elecraft detractor is going use it as
justification for writing something on another board to the effect that
Elecraft audio is bad. Shame on that person whoever it may be.

 

73, Erik K7TV

 

Bill W2BLC wrote:

It has been many years since I sat down to a Collins 75-S3. So long that I
cannot remember if they were really that good.

 

Anyone out there have a Collins receiver they'd care to compare to a K3? 

I am only interested in the quality of the receive audio. Of course there is
no DSP, memories, and all that.