[Elecraft] K3 Contest speech compression

[Jim Brown]

>>I opened by first time my compressor up to 30 

The digital readout is NOT the right way to set compression. Rather, 
switch the meter to the mode where it reads compression and ALC, and 
adjust the compression so that you get 10dB compression (as indicated on 
the meter) on peaks. 

>compressing a lot but still TX audio is clean, not distorded but very
>>powerful, with the use of the 8 bands EQ I have today and tomorrow
>>a very punchy high speech audio.

It is possible to make the K3 sound really great and very punchy, but it's 
also easy to make it sound just awful. 

My recommendations for TXEQ are to use maximum cut for the three lowest 
frequency bands no matter what mic you're using. If you're using a mic 
that has a peaky high end (communications mics like the Shure 444 and some 
Heil models), set all the other bands flat. If you're using a "flat" mic 
like a professional mic, leave the middle flat and boost the two top bands 
by 10dB. Make these adjustments BEFORE setting compression. 

Now, have a local station listen VERY carefully to your rig with their RX 
bandwidth set wide (like 2.7kHz or more). Make sure that there's no 
distortion (raspiness, brittle sound). Have them tune around with a narrow 
bandwidth, no preamp, low RF gain, noise blanker off, and make sure 
there's no splatter. If you're running USB, your highs should go away as 
soon as your signal gets outside their passband (within 1kHz or so for 
narrow RX filters, a bit more for a wider filter), and there should be no 
"crackle" from your audio no matter where they're listening. 

Another very important point. NEVER use ALC to set the output power for a 
linear amplifier. This is a recipe for splatter. Adjust power out by 
changing the output power from your transceiver. Also very important -- 
CAREFULLY TUNE YOUR AMP FOR MAXIMUM OUTPUT as indicated on the SWR meter. 
A poorly tuned amp is also a splatter geneator. It's OK to use ALC to 
protect your amp from disaster, but it should NOT be doing anything until 
something goes wrong. 

>You'd be one of the few who don't sound terrible.

YES!  This contest seems to have generated the worst audio I've heard for 
quite a while. Used to be some South Americans were the main offenders. 
Now more than half the stations I hear are badly distorted, and about half 
of those so distorted that it's hard to copy their call!  20M was a 
continuous grundge from one end to the other with wideband splatter. 

Let me be clear -- I'm a serious contester, and although I'm audio 
professional, I'm not a purist. Competitive audio SHOULD be well 
compressed, band limited, and with the response carefully shaped to punch 
through. But when you overdo it, it turns to trash, makes you hard to 
copy, and creates splatter. 

73,

Jim Brown K9YC