[TenTec] Orion 1 & 2 "Talk Power" problem

[Merle Bone]

Dennis (K8DO) said:
"An average of 800-900  with a 1400 peak is heavily, heavily compressed, is 
going to sound heavily compressed, is distorted <look at it on a scope>, and is 
not doing the transceiver or amp any favors, and is certainly not doing any 
favors for the folks who have to listen to it....  I have to say that I do not 
understand this need to see some big average number on the watt meter when 
talking, and have the sound of your breathing roaring in my ear, and your dog 
in the background, and the cars going by your house...... "
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Actually Dennis, I don't use that much compression except when chasing DX that is "tough " to get.
However, see my earlier post on this subject describing series of tests run with another ham, local friend, on 
10M. The compressed audio is very good. I'd be happy to demonstrate some time. You might also want to see 
Doug Smith's write up http://www.doug-smith.net/orion.htm on the approach he took to the Orion V1 compression (By the way, the V2 code isn't capable of nearly as much average talk power without the distortion you suggested). Doug Smith, describing the Orion V1 firmware, wrote:
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"Transmit Speech Processing in DSP

It might seem funny but in a DSP transmitter, it is relatively easy to compute the transmitter's RF envelope before the modulation is even performed! That, in turn, makes it possible to preprocess the audio applied to the modulator to get exactly the same effect as that produced by an RF compressor. See Fig 5. Post-modulation band-pass filtering maintains the desired occupied bandwidth. As the decay time of the compressor is decreased, an RF compressor approaches the behavior of an RF clipper, long known to be the most effective form of speech processing for SSB. In combination with the Orion's transmit equalizer, results are quite dramatic.

The reason RF compressors and clippers are so effective is that they increase the average power transmitted. Human voices tend to have high peak-to-average power ratios-- as high as 15 dB. That means a transmitter whose peak envelope power is limited to 100 W may achieve an average power of as little as 3 W. Under such conditions, the Orion's RF compressor may add 10 dB or more to the average power, equivalent to a ten-fold increase in output power. The speech processor achieves this goal without introducing the kind of distortion that harms intelligibility, such as that created by heavy audio compression or clipping.
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This is a very impressive capability of the V1 code and is the best speech compression I have ever heard. 
73, Merle - W0EWM