[Elecraft] Re: Microphone connections for K3 #1540

[Jim Wiley]

OK, I understand now.  The Gates company (of long ago broadcast 
equipment fame) made a device they called the "Level Devil" - which 
worked this way.  I had one, and it worked wonders in improving false 
vox trips.  The Level Devil served as a downward expander for signals 
less than the crossover point, and as a compressor for signals above the 
threshold.  Marvelous gadget - I wish I still had one.


- Jim, KL7CC



Iain MacDonnell - K6IAM wrote:
>
> google is a wonderful tool...
>
> http://www.doctorproaudio.com/doctor/temas/dynamics-processors-noisegates_en.shtml 
>
>
> "Downward expander. This type of unit works like the opposite of a 
> compressor, and provides a "ratio" control or attenuation slope. That 
> way the signal is attenuated more highly the lower the signal level 
> is. In fact, if the threshold is set high enough, we could "expand" 
> the dynamics of the signal, increasing its dynamic range, though this 
> is not normally done. The attenuation ratio works in an equivalent way 
> to that of the compressor, defining the amount of a attenuation 
> (compression) that is applied to the signal. These ratios are 
> expressed in dB, so that, for example, 1:6, means a signal that is 1 
> dB below the threshold will get reduced to 6 dB below it, while a 
> signal  3 dB below the threshold will get reduced to 18 dB below it. 
> Likewise, a 1:3 (one to three) means a signal 1 dB below the threshold 
> will be attenuated 2 dB (as the level will go from -1 dB to -3 dB; we 
> use a negative sign as these levels are below the threshold, which is 
> the 0 dB reference in this case). With a ratio of 1:10 and higher, the 
> expander is considered to work as a pure noise gate, though an ideal 
> gate would have a theoretical ratio of 1:infinity (any level below the 
> threshold would be totally muted). "
>
>     ~Iain
>
>
>
>
> Jim Wiley wrote on 09/ 1/08 11:16 AM:
>> I give up. What is a "downward expander"?  It that the same as a 
>> compressor?   Or is it something that has a "crossover point" that  
>> has one action on one side of the crossover, and  the opposite 
>> action  on the other side?   All these newfangled  terms are  simply  
>> amazing to us OFs.
>>
>> - Jim, KL7CC
>>
>>
>>
>> Lyle Johnson wrote:
>>>
>>> An experimental Downward Expander will be available in the K3 
>>> firmware in the near future.  It has been undergoing some limited 
>>> testing already
>>>
>>> _
>> _______________________________________________
>> Elecraft mailing list
>> Post to: Elecraft at mailman.qth.net
>> 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
>
>